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International Journal of Science and Engineering (IJSE)
Published by Universitas Diponegoro
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Core Subject : Engineering,
The scope of journal covers all area in the application on chemical, physical, mathematical, biological, agricultural, corrossion, and computer science to solve the engineering problems.
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Articles 16 Documents
Search results for , issue " Vol 8, No 2 (2015)" : 16 Documents clear
Assessment of Water Quality Using Macrobenthos as Bioindicator and Its Application on Abundance-Biomass Comparison (ABC) Curves Pawhestri, Suci Wulan; Hidayat, Jafron. W; Putro, Sapto P
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (250.35 KB) | DOI: 10.12777/ijse.8.2.84-87

Abstract

Abstract -Activities of aquaculture and industry which is directly adjacent to an aquatic environment may potentially result in increasing organic matter and causes a decreasing quality of water in it. Macrobenthos can be used as an bioindicators to detect environmental disturbances occur in the aquatic environment. This study aims to determine the level of environmental disturbance in aquatic environments using macrobenthic assemblages and their application in the abundance and biomass curves and it was compared to the values of diversity and similarity indices. Locations of this study is polyculture ponds and coastal of PT. Kayu Lapis Indonesian located in Mororejo Village, Central Java. Based on the abundance of macrobenthos results shows that in coastal area of PT. Kayu Lapis Indonesia is dominated by Cirratulidae (60%) from Polychaeta while in polyculture ponds is dominated by Potamididae (58%). Based on the abundance and biomass comparison (ABC) curves, the polyculture ponds were categorized as undisturbed area, whereas the coastal area of PT. Kayu Lapis Indonesia was categorized as moderately polluted for the second sampling time. Whilst the values of diversity (H’) and similarity (e) indices indicated low for all stations, the ABC curve of macrobetnhic assemblages is effective to  demonstrate the level of environmental disturbance occurs in aquatic environments.
INDONESIAN EFFORTS TO CONSERVE GEMBRONG GOATS Hasinah, Hasanatun; Inounu, Ismeth; Subandriyo, Subandriyo
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12777/ijse.8.2.88-94

Abstract

Gembrong goat are mainly found in eastern part of Bali Island, especially in the village of Tumbu, Karangasem. Throughout Indonesia these goats are found no more than 50 heads. This condition puts Gembrong goat in a critical status that indicates the need of emergency and quick action. The present study was carried out to assess the characteristic of this breed and to preserve it through some proposed action plan.  Information was obtained by personal observation and discussion with the leader of farmer group.  Body weight (BW) and various body measurement were taken from 15 head of Gembrong goat. In general, the color of Gembrong goat body is white, or partly brown or solid brown. The average body weight is of 23.2 kg for females and 30.7 kg for males.  The averages Body length of males is 60 cm, height 58.2 cm, and 14.4 cm ear length in males, and in females body length is 56.2 cm, height 55.1 cm and ear length 14.2 cm. To preserve Gembrong goat population from extinction collaborative activities is needed, namely: (1) multiplication of existing Gembrong goat population, (2) Rescuing animal genetic material and (3) up-grading female Kacang goat with Gembrong male goat as to achieve 99% Gembrong goat genetic composition.
Preparation of Natural Zeolite for Air Dehumidification in Food Drying Djaeni, Mohamad; Laeli Kurniasari, Laeli; Sasongko, Setia Budi
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (182.262 KB) | DOI: 10.12777/ijse.8.2.80-83

Abstract

Drying with air dehumidification with solid adsorbent improves the quality of food product as well as energy efficiency. The natural zeolite is one of adsorbent having potential to adsorb the water.  Normally, the material was activated to open the pore, remove the organic impurities, and increase Si/Al rate. Hence, it can enhance the adsorbing capacity. This research studied the activation of natural zeolite mined from Klaten, Indonesia as air dehumidification for food drying. Two different methods were used involving activation by heat and NaOH introduction.  As indicators, the porosity and water loaded were evaluated. Results showed both methods improved the adsorbing capacity significantly. With NaOH, the adsorbing capacity was higher. The simple test in onion and corn drying showed the presence of activated natural zeolite can speed up water evaporation positively. This performance was also comparable with Zeolite 3A
STUDY ADSORPTION DESORPTION OF MANGANESE(II) USING IMPREGNATED CHITIN-CELLULOSE AS ADSORBENT Lesbani, Aldes; Turnip, Ema Veronika; Mohadi, Risfidian; Hidayati, Nurlisa
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (435.802 KB) | DOI: 10.12777/ijse.8.2.104-108

Abstract

Abstract- Study adsorption desorption of manganese(II) using impregnated chitin-cellulose as adsorbent has been carried out. Chitin was extracted from snail shell and cellulose isolated from rice straw. Chitin and cellulose were impregnated using thiourea as impregnant agent. Characterization of chitin and cellulose was performed using FTIR spectroscopy, determination of water content, and ash content, while impregnated chitin-cellulose was characterized using FTIR spectrophotometer and X-Ray diffractometer. The adsorption of Mn(II) on impregnated chitin-cellulose was studied through determination of adsorption time and the influence of Mn(II) concentration, while desorption was carried out sequentially using various reagents. The results shown that chitin and cellulose from extraction processes are has similar FTIR spectrum compared to chitin and cellulose standard. The FTIR spectrum of impregnated chitin-cellulose shows both vibration of chitin and cellulose appeared and indicated successfully impregnate. These results were also equal to XRD pattern analysis. The water and ash contents of chitin are 0.038% and 0.043 while for cellulose are 0.184% and 0.165%, respectively. The adsorption of Mn(II) on chitin and cellulose are quite similar kinetically, while adsorption of Mn(II) on impregnated chitin-cellulose is higher at the same time with chitin and cellulose. In the low concentration of Mn(II), adsorption phenomena are similar on chitin, cellulose, and impregnated chitin-cellulose. Desorption process of Mn(II) on the adsorbents shows sodium etilenediamine tetra acetate able to desorp Mn(II) up to 68% higher than other reagents. Keywords: Manganese(II), Chitin, Cellulose, Impregnated Chitin-Cellulose
ANALYSIS OF CHEMICAL AND MICROBIAL CHANGE DURING STORAGE OF OVERRIPE TEMPEH POWDER AS SEASONING MATERIAL Hassanein, Tia Raisha; Prabawati, Elisabeth Kartika; Gunawan-Puteri, Maria Dewi Puspitasari Tirtaningtyas
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (134.89 KB) | DOI: 10.12777/ijse.8.2.131-134

Abstract

Tempeh and other soy-derived products are historically and currently some of the most important foods in the Asian region where diets remain predominantly plant-based. Overripe tempeh (tempe semangit) is a term used for over-fermented tempeh with pungent odor and darkening appearance commonly used in Javanese cuisine. Unique taste and odor of overripe tempeh lead to the exploration of its potencies as condiment, which may add the nutritional, safety and economic values of tempeh. In this research, overripe tempeh is made into powder for better appearance and availability. Oven drying at 60oC and freeze drying were applied to the overripe tempeh until it reached moisture content below 5%, followed by subsequent crushing into powder using electric grinding machine. As seasoning material, the tempeh powder and overripe tempeh powder were then analyzed for their stability. Observations in chemical and microbial changes during storage were also applied to selected product during storage. Parameters observed during the research are: moisture content, protein content, acid content, total microbial count and total coliform. Oven dried overripe tempeh (S60) has higher moisture content but lower in acid content, total microbial count and total coliform compared to freeze dried overripe tempeh (SFD).
THE EFFECT OF ANNEALING TEMPERATURES AFTER THERMOMECHANICAL PROCESS TO THE CORROSION BEHAVIOR OF Ni3(Si,Ti) IN SULFATE SOLUTION Priyotomo, Gadang; Kaneno, Yasuyuki
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12777/ijse.8.2.141-145

Abstract

The corrosion behaviour of the intermetallic compounds Ni3(Si,Ti) (L12: single phase), has been investigated using an immersion test, polarization method, scanning electron microscope in 0.5 kmol/m3 H2SO4 solution at 303 K.  Moreover, the corrosion behaviour of austenitic stainless steel type 304 was studied under the same experimental conditions as reference. It was found that the intergranular attack and uniform attack were observed on Ni3(Si,Ti) after thermomechanical and annealing processes (1173K and 1273K) respectively in the immersion test. From the immersion test and polarization curves, all annealed Ni3(Si,Ti) had less corrosion resistance compared to type 304. In addition, Ni3(Si,Ti) was difficult to form a stable passive film, but not for type 304.
Sensitization of Xanthophylls-Chlorophyllin Mixtures on Titania Solar Cells Kartini, Indriana; Dwitasari, L.; Wahyuningsih, T. D.; Chotimah, Chotimah; Wang, L.
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (279.743 KB) | DOI: 10.12777/ijse.8.2.109-114

Abstract

Co-sensitization of natural dyes on TiO2 for dye-sensitized solar cell (DSSC) was proposed between chlorophyllin (C) and xanthophylls (X at various volume ratios of C/X. Chlorophyllin is chlorophyll derivative providing -COOH groups essential for binding to TiO2. The chlorophyll was extracted from dried spinach (amaranthus viridis) leaves in a mixture of methanol-acetone (70%:30%). Chlorophyll extract dye was obtained after partition of the crude extracts in diethyl ether solution. Then, it was hydrolyzed under alkaline condition to get chlorophyllin. Xanthophyll was extracted from fresh petal of chrysanthemum (chrysanthemum indicum) flowers. Blending of chlorophyllin and xanthophyll was carried out at various volume ratios of C to X (1:0, 5:1, 1:1, 1:5, 0:1). Titania solar cells were constructed in sandwich system of conducting glass-titania/dyes as the photoanode and conducting glass-platinum as the photocathode. Electrolyte solution containing I-/I3- was inserted between the electrodes by capillary action. All dye extracts and blending solutions were analyzed by UV-Vis spectrophotometer. It is shown that the absorption spectra of blending dyes are complimentary in the visible region resulted in a panchromatic response of the dyes. From the cyclic voltammogram of the dyes and blended-dyes, it is found that the energy level of xanthophyll is the lowest. The I-V test at 100 mw/cm2 irradiation confirmed that the energy conversion efficiency (h) of the blended dyes of xanthophyll and chlorophyllin-sensitized solar cell resulted in significant improvement than those of the single dye. Beneficially, the mixed dyes can be adsorbed from solution blend using single dipping step.
Initial study of Nickel Electrolyte for EnFACE Process Widayatno, Tri; Roy, Sudipta
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (297.261 KB) | DOI: 10.12777/ijse.8.2.135-140

Abstract

Nickel electrolyte for a micro-pattern transfer process without photolithography, EnFACE, has been developed. Previous work on copper deposition indicated that a conductivity of ~2.7 Sm-1 is required. Electrochemical parameters of electrolyte i.e. current density and overpotential are also crucial to govern a successful pattern replication. Therefore, the investigation focused on the measurement of physicochemical properties and electrochemical behaviour of the electrolyte at different nickel concentrations and complexing agents of chloride and sulfamate. Nickel electrolytes containing sulfamate, chloride and combined sulfamate-chloride with concentrations between 0.14 M and 0.3 M were investigated. Physicochemical properties i.e. pH and conductivity were measured to ensure if they were in the desired value. The electrochemical behaviour of the electrolytes was measured by polarisation experiments in a standard three-electrode cell. The working electrode was a copper disc (surface area of 0.196 cm2) and the counter electrode was platinum mesh. The potential was measured againts a saturated calomel reference electrode (SCE). The experiments were carried out at various scan rate and Rotating Disc Electrode (RDE) rotation speed to see the effect of scan rate and agitation. Based on the measured physicochemical properties, the electrolyte of 0.19 M nickel sulfamate was chosen for experimentation. Polarisation curve of agitated solution suggested that overall nickel electrodeposition reaction is controlled by a combination of kinetics and mass transfer.  Reduction potential of nickel was in the range of -0.7 to -1.0 V. The corresponding current densities for nickel deposition were in the range of -0.1 to -1.5 mA cm-2.
Correlation Equations of Heat Transfer in Nanofluid Al2O3-Water as Cooling Fluid in a Rectangular Sub Channel Based CFD Code Ramadhan, Anwar Ilmar; Lasman, As Natio; Septilarso, Anggoro
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1085.853 KB) | DOI: 10.12777/ijse.8.2.120-124

Abstract

Safety is a major concern in the design, operation and development of a nuclear reactor. One aspect of nuclear reactor safety factor is thermal-hydraulics aspect. In a PWR-type nuclear power plant has been used lighter fluid coolant is water or H2O. In this research, using nanofluid Al2O3-Water with volume fraction of (1%), (2%) and also (3%), used as a cooling fluid in a nuclear reactor core with sub channel PWR fuel element rectangular arrangement. This research was carried out modeling of fuel elements are arranged rectangular, then performed numerical simulations using Computational Fluid Dynamics (CFD) code. In order to obtain the characteristic pattern of flow velocity of each fluid, the fluid temperature distribution along the cylinder wall temperature distribution of the fuel element. Then analyzed the heat transfer in a nuclear reactor core with sub channel PWR fuel element rectangular arrangement, including heat transfer coefficient, Nusselt number (Nu), as well as heat transfer correlations. Heat transfer correlation for nanofluid Al2O3-Water (1%), (2%) and also (3%) proved to core of PWR nuclear reactor fuel element sub channel rectangular arrangement with the Reynolds number (Re) is stretched, namely: 404 096 <Re <423 084 and with constant heat flux is 2600 W / m2, and the composition ratio (pitch / diameter) 1.33.
Heat and mass transfer effects on an unsteady mhd flow of a rotating fluid past a vertical porous plate Murali, G; Reddy, E.M.; Venkata N. B, Narepalepu
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (250.764 KB) | DOI: 10.12777/ijse.8.2.95-103

Abstract

An attempt is made to investigate the heat and mass transfer effects on an unsteady free convection flow of a rotating, incompressible, viscous Boussinesq fluid in presence of first order chemical reaction. The governing dimensionless equations for this investigation are solved numerically by a finite element method. A parametric study illustrating the influence of different flow parameters on velocity, concentration and temperature are investigated. Also the Skin – friction, Nusselt number and Schmidt number are shown through tabular forms. Numerical results are presented for various parameters.

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