Simulation of sub-drains performance using visual MODFLOW for slope water seepage Problem

Numerical simulation technique was used for investigating water seepage problem at the Botanic Park Kuala Lumpur. A proposed sub-drains installation in problematic site location was simulated using Modular Three-Dimensional Finite Difference Groundwater Flow (MODFLOW) software. The results of simulation heads during transient condition showed that heads in between 43 m (water seepage occurred at level 2) until 45 m (water seepage occurred at level 4) which heads measurement are referred to mean sea level. However, elevations measurements for level 2 showed the values between 41 to 42 m from mean sea level and elevations for level 4 between 42 to 45 m from mean sea level. These results indicated an increase in heads for level 2 and level 4 between 1 to 2 m when compared to elevations slope at the level 2 and level 4. The head increases surpass the elevation level of the slope area that causing water seepage at level 2 and level 4. In order to overcome this problems, the heads level need to be decrease to 1 until 2 m by using two options of sub-drain dimension size. Sub-drain with the dimension of 0.0750 m (diameter), 0.10 m (length) and using 4.90 m spacing was the best method to use as it was able to decrease the heads to the required levels of 1 to 2 m

Simulation of sub-drains performance using visual MODFLOW for slope water seepage Problem

Numerical simulation technique was used for investigating water seepage problem at the Botanic Park Kuala Lumpur. A proposed sub-drains installation in problematic site location was simulated using Modular Three-Dimensional Finite Difference Groundwater Flow (MODFLOW) software. The results of simulation heads during transient condition showed that heads in between 43 m (water seepage occurred at level 2) until 45 m (water seepage occurred at level 4) which heads measurement are referred to mean sea level. However, elevations measurements for level 2 showed the values between 41 to 42 m from mean sea level and elevations for level 4 between 42 to 45 m from mean sea level. These results indicated an increase in heads for level 2 and level 4 between 1 to 2 m when compared to elevations slope at the level 2 and level 4. The head increases surpass the elevation level of the slope area that causing water seepage at level 2 and level 4. In order to overcome this problems, the heads level need to be decrease to 1 until 2 m by using two options of sub-drain dimension size. Sub-drain with the dimension of 0.0750 m (diameter), 0.10 m (length) and using 4.90 m spacing was the best method to use as it was able to decrease the heads to the required levels of 1 to 2 m

Pengaruh Ion Logam Cu(II) terhadap Persen Ekstraksi Ion Pb(II) Menggunakan Teknik Emulsi Membran Cair

This study aimed to determine effect of Cu(II) ion toward percent extraction of Pb(II) ion using emulsion liquid membrane technique. Variation concentrations of Cu(II) added were 0, 50, 100, 150, 200 and 250 ppm with the initial concentration of Pb(II) was 245 ppm. This extraction used benzoyl acetone as a chelating agent. The extraction results were measured by Spectrodirect. The results showed that percent extraction of Pb(II) ion prior addition of Cu(II) ion was 99.09%, but after addition of Cu(II) to a concentration up to 250 ppm, the percent extraction of Pb(II) ions turned to decrease by 97.92%

Pengaruh Bentuk Lambung Kapal Terhadap Pola Aliran Dan Powering Pada Kapal Perairan Sungai Dan Laut

Bentuk lambung haluan kapal yang tepat sangat berpengaruh pada perbaikan pola aliran air maupun penurunan tahanan gelombang yang ditimbulkan badan kapal saat beroperasi. Pada tulisan ini dilakukan kajian tentang pengaruh bentuk lambung haluan kapal yang diwakili oleh Model-A dan Model-B terhadap pola aliran, tahanan dan daya poros pada kapal yang merupakan salah satu jenis kapal perairan sungai-laut. Pada Model-B dilakukan modifikasi bentuk haluan dari Model-A. Dari hasil simulasi didapatkan bahwa peningkatan daya poros sebesar 12% saat kecepatan 14.5 knot pada Model-B atau keuntungan 3% dari penambahan displaceament 15% pada Model-B dari bentuk asli Model-A dengan operasional optimum kapal adalah pada kecepatan antara 12 dan 15 knots

Karakteristik Ekologi Dan Aspek Silvikultur Eboni (Diospyros Celebica Bakh.) Sulawesi Selatan

This paper describes the ebony (Diospyros celebica Bakh.)site characteristics in Amaro Forest,Barru District, South Sulawesi including its secondary succession to create a favourable conditions for stand establishment. Association analysis shows that a wide variety of lowland species have been identified grows together with the ebony.Physical characteristics rather than chemical fertility of soils show a great value in supporting ebony stand growth.Poor stand with low natural regeneration of these remaining fragmented forests suggest the need to apply enrichment planting and improvement cutting to increase their productivity

Adsorption of brilliant green dye in aqueous medium using magnetic adsorbents prepared from rice husk ash

Large scale production and extensive application of synthetic dyes in the textile industry have caused considerable environmental pollution. The treatment of colored effluents using efficient technologies, are sought after due to this concern. This research evaluates the effectiveness of magnetic adsorbent (MRHA) prepared from rice husk ash (RHA) by a chemical processing method to remove brilliant green (BG) dye from an aqueous medium. The resulting MRHA adsorbents were tested at different initial concentration of 5-400mg/L, adsorbents amount of 0.5-2.3g, shaking rate of 50-300rpm, contact time of 15-120 min, pH of 3-11, and temperature of 27-60 C. A maximum removal of 96.65% was obtained at initial dye concentration of 200mg/L, adsorbents amount of 2g, shaking rate of 150rpm, contact time of 60min, and temperature of 50 C. The fresh and spent MRHA adsorbents were analyzed through scanning electron microscopy (SEM) and particle size distribution. The particle analysis of the fresh and spent adsorbents indicated bimodal pore size of 90 and 900 μm, respectively. The adsorption behavior of the adsorbent followed those of the Langmuir, Freundlich, and Temkin isotherm models. However, Temkin isotherm model displayed the best fit with the coefficient of determination, R2 of 0.811, suggesting a strong interaction, equivalent to that of chemical absorption between BG dye molecules and the surface of MRHA adsorbent for effective removal of BG dye from the aqueous medium. The magnetic character of the adsorbents allowed the spent sample to be isolated successfully and conveniently by using an external magnetic field

Influence of Microstructural Effect on Microvickers Hardness Properties of SiO2-Na2O-CaO (SNC) Waste Based Glass-ceramic

There are a lot of waste materials consist of silicate based such as coal combustion ash, slag from steel production, fly ash, mud, as well as glass cullet or mixtures to produce glass-ceramics. This research work using clam shell (CS) ash and soda-lime-silica (SLS) waste glass powder for fabricating novel SiO2-Na2O-CaO (SNC) glass-ceramic. The samples were composed of SLS (50%), Na2CO3 (30%), and CS (20%) in weight percentage via conventional melt-quenching technique and solid-state sintering technique. The samples were investigated via X-Ray Diffractometer (XRD), Field emission microscope (FESEM), and microvickers hardness tester. The samples were sintered at 550-950 °C to investigate the influence of microstructural effect on microvickers hardness properties at applied force 0.5 and 1.0 kgf. The optimal Vickers hardness properties at sintering temperature 850 °C due to high crystallization of SiO2 phase from the residual glass and CaO content enhanced the viscosity flow, high compactness of particles arrangement and densification of sample

Influence of Microstructural Effect on Microvickers Hardness Propertiesof SiO2-Na2O-CaO (SNC) Waste Based Glass-ceramic

There are a lot of waste materials consist of silicate based such as coal combustion ash, slag from steel production, fly ash, mud, as well as glass cullet or mixtures to produce glass-ceramics. This research work using clam shell (CS) ash and soda-lime-silica (SLS) waste glass powder for fabricating novel SiO2-Na2O-CaO (SNC) glass-ceramic. The samples were composed of SLS (50%), Na2CO3 (30%), and CS (20%) in weight percentage via conventional melt-quenching technique and solid-state sintering technique. The samples were investigated via X-Ray Diffractometer (XRD), Field emission microscope (FESEM), and microvickers hardness tester. The samples were sintered at 550-950 °C to investigate the influence of microstructural effect on microvickers hardness properties at applied force 0.5 and 1.0 kgf. The optimal Vickers hardness properties at sintering temperature 850 °C due to high crystallization of SiO2 phase from the residual glass and CaO content enhanced the viscosity flow, high compactness of particles arrangement and densification of sample

Electromagnetic Interference (EMI) Analysis on Surface Roughness of 3C-Silicon Carbide (3C-SiC) Deposited on Silicon (Si) Substrate

Electronic devices may produce undesirable electromagnetic (EM) interference which can degrade the system performance and also affect human health. In this paper, the potential property of 3C-Silicon Carbide (3C-SiC) as the microwave absorbing material is investigated. The reflection coefficient, Г of 3C-SiC has been measured using an open-ended coaxial sensor. The substrates consisted of films of 3C-SiC of two different thicknesses (0.265µm and 0.285µm) with both polished and unpolished surfaces. The measurements were taken in the frequency range within 1.4 GHz to 18.8 GHz at room temperature. A continuous decrease in the reflection coefficient was measured in 3C-SiC as the frequency increased to 18.8GHz. The results have shown that the rougher surface of unpolished 3C-SiC of 0.285µm thickness could be applied as microwave absorbing material