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A novel application of sodium dodecyl sulphate-polyacrylamide gel electrophoresis was evaluated to differentiate the quality of two commercial cinnamon bark oil samples extracted by steam distillation and cold pressed. Prior to the electrophoresis, cinnamon oils were emulsified with non-ionic surfactant, tween 80 at 2% v/v of critical aggregation concentration. The droplets prepared were within 30 to 70 nm size and zeta potential values of -4 to -12 mV consisted of certain amount of bioactive compounds that responded to specific molecular mass and electrophoretic mobility so that separation using SDSPAGE can be performed. The resolution bands at 21% gel with 48% acrylamide concentration and 3.33% of cross-linker demonstrated that high quality (steam distilled) cinnamon oil migrated slower through gel due to its large molecular weight components when compared to the low quality (cold pressed) cinnamon oil. The difference in the relative mobility, 0.68 and 0.75 of emulsified steam distilled and cold pressed cinnamon bark oils, respectively, was attributed by their entrapped components impinging upon their electrophoretic mobility.

The potential of Tween 80, a commercial food-grade non-ionic surfactant, was evaluated for the extraction of residual oil from palm-pressed mesocarp fibre (PPMF). Results show that the critical micelle concentration (CMC) was achieved at 0.05 wt% surfactant with an interfacial tension (IFT) of 0.51 mN/m. The extraction yield however depends not only on the IFT but also on the viscosity and the solid to liquid ratio of the extracting solution. The highest percentage of oil extraction (47.36%) was obtained at 1 wt% Tween 80 with 6% NaCl, temperature of 60°C and a solid–liquid ratio of 8 g PPMF: 200 g solution.

Nowadays, contents of pesticide residues in vegetables had become one of the hot topics closely related to human health. In order to investigate the effectiveness of several cleaning solutions in removing pesticide residues in vegetables, a polluted cauliflower was washed using five types of cleaning solutions which were soda-salt solution, vinegar solution, tamarind juice solution, filtered flour solution, and tap water. Chlorpyrifos was extracted from residues cleaning process and cauliflower itself. Gas chromatography-electron capture detector was used to identify content in residues cleaning process (RCP). Tamarind juice solution had the greatest removal effect, in relation to other of cleaning solutions, with 93.04% removal rate followed by filtered flour solution (17.03%) and vinegar solution (11.42%). However, soda-salt solution and tap water did not have any removal effect in removing chlorpyrifos in cauliflower. Tamarind juice solution was significantly higher than other types of cleaning solutions and tamarind juice solutions itself is a natural fruit juice and non-chemical substance with very easy preparation; therefore, the tamarind juice solution can be used as a general-purpose cleaning solution to remove chlorpyrifos residues in cauliflower. Key words: Pesticide residues, chlorpyrifos, cleaning solutions, removal effect.

The thiosemicarbazone (TSC) derivative chelate was synthesized by condensation of 2-hydroxybenzaldehyde with substituted thiosemicarbazide. Eight mono and binuclear transition metal(II) complexes of TSC derivative have been prepared in 1:1 and 2:1 (M:TSC) ratios. Elemental analysis, molar conductivity, magnetic measurements, thermogravimetric, UV–Vis., FTIR, 1H NMR, and mass spectra have been used to identify those complexes. The 1:1 complexes have the general formula [M(TSC)(NH3) x(Cl)y(H2O)z]. nH2O, where M = Ni, Cu and Zn, x = 3, 3 and 1; y = 1; n = 2, 2 and 3 respectively, while Co(II) complex has formula [Co(TSC)(NH3)2(Cl)(H2O)]·6H2O. The binuclear 2:1 complexes have the general formulas [Co2(TSC)(NH3)2(Cl)2(H2O)4]·2H2O, [Ni2(TSC)(NH3)4(Cl)2(H2O)2]·4H2O, [Cu2(TSC)(NH3)4(Cl)2(H2O)2]·2H2O, and [Zn2(TSC)(NH3)2(Cl)2] 2H2O respectively. The mononuclear and binuclear complexes are found to have distorted octahedral stereochemistry in which one of the central metal ions is bonded to TSC chelate through phenolate oxygen atom and azomethine nitrogen atom, while in case of binuclear complexes the other central metal ions is coordinated toward TSC chelate via two oxygen atoms of carboxylate group that associated from the hydrolyses of the terminal cyano group. The TSC ligand and its complexes have been studied for their possible biological activity including antibacterial and antifungal activity.

Air pollution has long been and is still a problem for humans and the environment, a priority in countries with high vehicle rates. The contribution of gas released reaches 60-70%. Motor vehicles produce one of the pollutants, namely Carbon Monoxide (CO) gas. This research was conducted to determine the level of CO concentration results from sampling using impinger and prediction models using Caline4 software. The results of the concentration between direct measurements with the Caline4 model were then compared. This research was conducted in three streets for three working days namely Jl.Urip Sumoharjo, Jl.Talasalapang, and Jl.Nusantara. The methodology used is direct measurement using impinger, calculating vehicle volume at each measurement point, and analyzing CO concentrations using Caline4. The results of sampling showed the highest CO concentration on Jl.Urip Sumoharjo at 5.80 ppm, Jl.Talasalapang at 1.06 ppm, and Jl.Nusantara 1.15 ppm. The highest estimation results of CO concentrations with Caline4 on Jl.Urip Sumoharjo were 5.7 ppm, Jl.Talasalapang by 1.1 ppm, and Jl. Nusantara was 1.4 ppm. High or low CO concentration value depends on vehicles volume, for instance, CO concentration increases with increasing vehicles volume. In addition, it is also depends on the meteorological factor, such as, the faster the wind increases, the faster the pollutants will increase. Then compare the results of CO impinger concentration and Caline4 using the t-Test to see the difference of the two CO concentrations. Comparisons were made using the t-Test to meet the t-stat < t-critical concluded that there was no significant difference between the two CO concentrations.

The Hasanuddin University Faculty of Engineering in Gowa is the largest engineering campus in South Sulawesi. The lecture activities are very complex which are not only teaching and learning but also households and offices activities. Therefore, it is important to know the mapping of existing carbon footprint on the campus due to the complexity of the campus activities. The purpose of this study is to determine the level and mapping of the carbon footprint on campus. The method used is to halve emissions into primary and secondary carbon footprint emissions. The results of this study indicate that the greatest emissions is generated from the secondary carbon emissions which is electricity consumption amounting to 1,315,429.63 KgCO2/Year, and the lowest emissions is resulted from the use of paper at 49.39 kgCO2/Year. For the buildings the highest CO2 emissions is generated from the Architecture Department building at 289,176.26 KgCO2/year and the lowest CO2 emissions is generated from the Naval B Department building at 20,599.20 KgCO2/year. The mitigation scenario in reducing CO2 emissions effectively is by implementing Earth Hour for 1 hour every month which can reduce electricity consumption by 582,541.78kWh/Year and CO2 emissions at 164,428.70 KgCO2/year. The effective scenario to decrease waste is by implementing 3R with 2% waste reduction which is 167,332.79 Kg/Year and emissions CO2 are 4,772.41 KgCO2/Year.

The economic growth will increase the transportation sectors roles in supporting the achievement of development goals. But transportation activities have negatives impact, where one of the negative impact of transportation activities is the high levels of pollutants due to emissions or release of smoke from motor vehicles. This study aims to determine the capability of green open space that exists, especially in the ability of trees and shrubs in absorbing carbon monoxide and carbon dioxide emissions generated by motor vehicles operating in Balai Kota Makassar. The research is qualitative. All data required for the analysis of the research are primary data or data obtained directly in the field. Primary data in this research are data obtained by counting the number of vehicles and the area cover by vegetation canopy. In this research, zonation system is applied because each area has different green open space requirement based on the emission load generated by motor vehicles passing in the area so that the research location is divided into 4 zones. To calculate the vehicle’s emission, it applies the equation of emission strength, and to calculate the emission absorption by vegetation is use vegetations area covers. The results showed in zones 1, zone 2 and zone 3, green open space existing already can absorb 100% carbon dioxide emissions and carbon monoxide. But in zone 4, green open space existing cannot absorb 100% carbon dioxide emissions and carbon monoxide.

TiO2 nanoparticle based interdigitated microelectrode was fabricated by spin-coating and conventional photolithography approaches. Aluminum metal was deposited by thermal evaporator on silicon dioxide substrate. The effect of aluminum microelectrode gap sizes (4, 5 and 6 µm) on the electrical performance was investigated using picoammeter. Extremely small output current values of three different gap sizes were acquired. A characteristic electrical behavior was observed for the studied geometry. The configuration demonstrated a reduction in the output current from 2.28E-10, 1.32E-9 and 2.38E-9 A with increasing gap size.TiO2 nanoparticle based interdigitated microelectrode was fabricated by spin-coating and conventional photolithography approaches. Aluminum metal was deposited by thermal evaporator on silicon dioxide substrate. The effect of aluminum microelectrode gap sizes (4, 5 and 6 µm) on the electrical performance was investigated using picoammeter. Extremely small output current values of three different gap sizes were acquired. A characteristic electrical behavior was observed for the studied geometry. The configuration demonstrated a reduction in the output current from 2.28E-10, 1.32E-9 and 2.38E-9 A with increasing gap size.

Lanthanum doped barium titanate (BaTiO3) were studied for high-K dielectric and exhibit a relaxor ferroelectric properties and it can be prepared by using various method. Relaxor ferroelectric offers a wide temperature and frequency range of application for materials with high dielectric constant for microelectronic application. This paper reviews the preparation methods, the important features, advantages and limitation for the lanthanum doped barium titanate. Thus, the phase purity and mixture selected also been review on the second part of the article. The article concludes with a brief discussion of the methods with good dielectric behavior. The objectives of this paper are to determine the selection of suitable preparation methods and the properties of the high-K dielectric based on pure barium titanate and lanthanum doped barium titanate.

Growth of titanium dioxide (TiO2) nanowires was studied on the seed layer of TiO2 through hydrothermal growth method. Here, the growth of nanowires TiO2 on Si (100) substrates by using the two steps method. Different seed layers of TiO2 were prepared by using sol-gel method, deposited by spin coating and annealing, followed by the growth of TiO2 nanowires by using the hydrothermal method. Acetic acid was used as a stabilizer to synthesize a TiO2 seed layer. The aim of this study was to understand the role of polycrystalline size on thin film towards the diameter of nanowires grown as a sensing area in Surface Acoustic Wave (SAW) Biosensor. The morphology and microstructure of the thin film seed layer and TiO2 nanowires were characterized using X-Ray diffraction (XRD), scanning electron microscope (SEM), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM).

In this paper investigated into the effect of a bio-interface charge field effect biosensor on the conductance of the nanowire through finite element calculations. The biosensor under thought consisted of a poly-silicon nanowire of radius 100 nm surrounded by a 120 nm oxide layer, and the oxide layer was surrounded by a 160 nm thick functional bio-interface layer. This whole system was immerged in an electrode was 500 nm and every one of the layers was treated as a range medium characterized by the corresponding dielectric constant. First, the distribution of the electrostatic potential in the nanowire due to the surface charge was computed using Poisson equation with Boltzmann statistics. Then, the conductance of the nanowire was affected with interaction with functional layer.

Synthesis of titania or titanium dioxide (TiO2 ) is attracted to energy and environmental applications. Here, the growth of nanostructure TiO2 nanowires on Si (100) substrates by using the two-step method. Different seed layers of TiO2 were deposited by spin coating and annealing, followed by the growth of TiO2 nanowires by using the hydrothermal method. The sol-gel technique was used in preparing the TiO2 solution for the thin film deposition purpose. Acetic acid, hydrochloric acid and tris (2-aminoethyl) amine were used as a stabilizer to synthesize three different TiO2 seed layers. The aim of this study was to understand the role of polycrystalline size on thin film towards the diameter of nanowires grown as a sensing area in Surface Acoustic Wave (SAW) Biosensor. The morphology and structure of the thin film and TiO2 nanowires were characterized using X-Ray diffraction (XRD), scanning electron microscope (SEM), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM).

To develop the SAW device, piezoelectric substrate is one of important factor that improve performance device. The material used such as ITO (Indium Thin Oxide) or LiTaO3 (Lithium Tantalate) extremely affect the cost as well as the preparation methods. To overcome this problem, the material known as ZnO (Zinc Oxide) has been chosen as the thin film layer of piezoelectric in developing the biosensor. These ZnO thin film acts as piezoelectric layer that made contact with the sensing element before the signal convert from a biological signal to an electrical signal by the transducer. Solgel deposition technique was used and zinc acetate as precursor compound and 2-Methoxyethanol as solvent to form the sol-gel. This sol-gel then be spin coat on the SiO 2 /Si substrate which will later to be anneal with oxygen to make the thin film more dense, thinner and has smoother surface quality and higher resistivity. The surface morphology, electrical and optical characterization of the thin films will be studied using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM), Four Point Probe and UV-Visible Spectropohotometer.

The limitation of human five main senses to detect the Nano-scale organism has introduced the idea for researcher in development several kinds of devices or sensors. The Surface Acoustic Wave (SAW) devices which wisely use in telecommunication field at the early time had been integrated into biosensor which able to detect the microorganism in aqueous state. Typically, a SAW sensor will have three elements which are transducers, sensing area and electronic signal processor. Zinc Oxide (ZnO) thin film use as piezoelectric substrate while metallic material as Inter Digital Transduces (IDTs). The new device structure which replaces the sensing area by using ZnO metal oxide layer is conducted in this study. Hence, the purpose is to investigate the behavior of various sizes of ZnO metal oxide layer as sensing area for the SAW device. Conventional lithography and Therefore, ZnO thin film layer by Sol-gel method is applicable use as SAW device. ZnO Sol-gel coating method were used to fabricate the SAW device. The SAW device with ZnO metal oxide layer shows the attractive result. The electrical characteristic and frequency response were used to assess the behaviour of the SAW device. X-ray Diffraction (XRD) and Atomic Force Microscope (AFM) was used to evaluate the ZnO structures.

Surfactant-assisted aqueous extraction has been proposed as a "green" alternative to hexane extraction for the recovery of oil from plant matters. An efficient aqueous surfactant extraction system usually use an extended type of ionic surfactant with the ability to produce Winsor type III microemulsion, reducing the interfacial tension (IFT) between plant oil and surfactant solution to an ultralow level (10-3 mN/m). However, the safe used of this surfactant in food processing is uncertain leading to non-food application of the recovered oil. In the present study, the potential of Tween 80, a commercial food-grade non-ionic surfactant, was evaluated in the recovery of residual oil from palm-pressed mesocarp. The emulsion produced between Tween 80 and crude palm oil (CPO) was characterised in terms of IFT, droplet size, viscosity and phase inversion temperature (PIT). The effect of surfactant concentration, electrolyte (NaCl) and temperature were studied to determine whether a Winsor Type III microemulsion can be produced. Results shows that although these parameters were able to reduce the IFT to very low values, Winsor type III microemulsion was not produced with this single surfactant. Emulsion of CPO and Tween 80 solution did not produce a PIT even after heating to 100°C indicating that middle phase emulsion was not able to be formed with increasing temperature. The highest percentage of oil extraction (38.84%) was obtained at the concentration above the critical micelle concentration (CMC) of Tween 80 and CPO, which was at 0.5 wt% Tween 80 with 6% NaCl, and temperature of 60°C. At this concentration, the IFT value is 0.253 mN/m with a droplet size of 4183.8 nm, and a viscosity of 7.38 cp.

Dammar is a natural resin was mixed with silicone resin (SD) to be new modified silicone coating binder. The sample was varied by weight % and designated as SD0, SD5, SD10, SD15, SD20, SD25, SD30, SD35, SD40 and SD45. The dried coating film layer was coated on aluminum q-panel using spin coat er. The cured sample was mounted an open tube and filled with 3% of sodium chloride to measure ion conductivity using impedance spectroscopy (EIS). While a custom chamber was made to act sandwich like chamber to measure thermal conductivity of the cured sample As the result, SD15 and SD25 show higher coating resistance at 6.0E+06 and 8.0E+06 S/cm respectively. However ionic transference number showed the ionic activity up to 1.0V in SD10, SD15 and SD25. Thus, SD5, SD10 and SD15 show the low of k-value at 0.01, 0.02 and 0.03 W/mK respectively. XRD spectra indicate the dammar content could influent the ionic and thermal conductivity of SD coating resin when sharp peak of silicone resin gives the different intensity at SD10, SD15, SD20 and SD25.

Dammar plant resin (dipterocaupecea sp .) was mixed with silicone in various wt% and these two components were modified by using a volatile organic solvent. A thin coating film layered on aluminium Q‐panel was applied using spin coating method and cured at room temperature. Electrochemical Impedance Spectroscopy (EIS) analysis was done to investigate the corrosion potential property of the coating and it was found that 15wt% of dammar content increased the coating resistance up to 2.88E+07 S/cm after exposure to 3% of NaCl solution for 15 days. Results from infra red analysis (FTIR) revealed that some changes in the structure of Silicone‐Dammar (SD) organic binder system has occurred.

Dammar, a local plant resin (Dipterocaupacea sp) has been used in coating formulation to produce dammar‐modified silicone resin. Dammar and silicone were mixed in various compositions and then were coated onto Aluminum Q‐panel by using spin coating method and left to dry at room temperature. Adhesion property was investigated by using impact test and pull‐off test. There were no significant damage and delaminations were observed at the panel coated with 15 wt.% of dammar that has undergone the impact test. Hence, the addition of more than 15 wt.% of dammar resulted in large delaminations and cracks on the coating materials. Results from pull off test also showed that 15 wt.% of dammar organic coating has strong adhesion, 108 Psi. It made 15 wt% as optimized composition. This optimized composition was added with nanopowder as rheological modifier or additive. Again the modified samples were undergone the impact and pull off test to study the effect of adhesiveness. Contact angle measurement of wettability test was also being carried out. The surface coated with dammar‐silicone resin was found to be hydrophobic where the contact angle obtained was 70° for the sample containing 10 wt% of dammar. The additional of nanopowder into optimized composition exhibited more hydrophobic phenomenon which approached towards bio‐mimicry behaviour, when water droplets simply rest on the surface without actually wetting the surface to any significant extent (hydrophobic) where the angle of wetting tests more than 90° have been achieved.

This study evaluated the effects of a liquid dispersing agent (LDA) and a microcrystalline additive (MCA) on selected physical properties of type IV gypsum. Working consistency, setting time, setting expansion, and compressive strength (1 hour and 7 days) were determined, following ADA Specification No. 25, on a standard, LDA (0.5, 1, 1.5, and 2 mL), MCA (21.1, 24.1, and 27.1 gm), and combination (LDA 0.75 mL + MCA 12.05 gm) mixes per 300 gm of gypsum. Results indicate that the additives affect the consistency of the mix, but consistency can be kept close to that of the standard by lowering the water/powder ratio. Statistical analysis of the data indicated that the additives significantly affected the setting time, setting expansion, and both the 1-hour and the 7-day compressive strengths. SEM examination of fractured surfaces of test mixes indicated improved crystal packing. The properties of type IV gypsum can be improved by optimizing the amount of LDA and MCA additives.