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Analysis of the levels of heavy Metal in refill using Atomic Absorption Spectrophotometry (AAS)
Full text linkResearch on determining the levels of lead (Pb), iron (Fe) and manganese (Mn) in refill drinking water at 3 depots in Palu city, namely Manimbaya’s depot, KH Dewantoro’s depot and Tombolotutu’s depot, has been conducted. The determination of metal concentration was analyzed using Atomic Absorption Spectrophotometry (AAS). Results of this analysis show that the iron (Fe) concentrations were 0.1278 mg/L, 0.1426 mg/L, and 0.1059 mg/Lat the Manimbaya’s depot, KH Dewantoro’s and Tombolotutu’s, respectively. Similarly, the manganese (Mn) concentrations were0.1927 mg/L, 0.1240 mg/L, and 0.1538 mg/L at Manimbaya’s depot, KH Dewantoro’s, and Tombolotutu’s, respectively. Keyword: Refill drinking water, metal of lead (Pb), metal of iron (Fe), metal of Manganese(Mn), Atomic Absorption Spectrohotometry (AAS)
Determining the structure of Rock areas land sliding USING SEISMIC MIKROTREMOR in the Village Enu Sindue, Donggala District
Full text linkThe research using refraction of micro-tremor has been conducted in the Village of Enu,Districtof Sindue, Regency of Donggala. Refraction seismic method of micro-tremor is an effective and efficient method for determining the shear wave velocity of rock bedding. This study aims to determine the structure of the soft soil layers that have the potential landslides as well as determining the value of the depth of each layer. Data taking of used 24 channel geophones which spaced 3 meter between geophones and 3 tracks. Data processing was done in 2 stages: first stage using Surface Wave Analysis Wizard program to get phase velocity relation as a function frequency and the second stage using WaveEq program to obtain the shear wave velocity (Vs) as a function of depth (m). Interpretation performed to infert the structure of geological layers below the surface based on the value in the medium speed of shear wave propagation velocity. The interpretation results of shear wave velocity for 1-st track is located on the third layer with depth of12 m and Vs = 105 m/s, for 2-nd track is located also on third layer with a depth of 9 m and Vs = 80 m/s, and for the 3-rd track is laid on 2-nd layer with a depth of 8 m and Vs = 105 m/s. The soft rocks that acts as a sliding plane is granite and claywhich covered limestone with Vs = 80 m/s-105 m/s and the depth of 8 m-12 m. Kata kunci: micro-tremor refraction, shear wave, bedrock, landslide. Â
Accuracy and Automatic Computation of Seismic Refraction: a case of Forward Modeling and Inversion
Full text linkIt has been built a data processing program to perform the first arrival waktu tempuh inversion of seismic refraction profiles zero distance. Analysis of the first wave arrival time is obtained by 1) using two-way analysis of time-taking to control the accuracy of the passage and identify the mistakes geometry,, 2) parameterization slowness and intercept-time of travel-time, in which the velocity model and multi-layer thickness obtained by inversion LSQ method (unconstrained, constrained and Marquardt) on seismic refraction. For automatic calculation and accurate, we make a data processing program for the third inversion LSQ method. Analysis of the model resolution and measurement data to determine the optimal parameters of the model, the algorithm used Menke (1989). Resolution inversion results, we tested with: forward modeling, the level of misfit (error) and the convergence between the observed data and the model. Once the program is successfully tested on a number of data, then we apply to the real seismic. The results of field data inversion interpreted that the subsurface strata bedding row from the top (first layer) in the form of: soil, sand (loose), sand (saturated, loose) and sandstone, limestone. Resolution velocity and thickness in the forward modeling program: a) the error between: 10-17 - 10-5 and b) the residue of convergence is: 10-11-10-4, while the resolution of the results of the third inversion LSQ method on the field data, obtained misfit between: 10-17 - 10-4 and residual convergence between measurement data and the model are: 10-11 -10-4.Keywords —seismic refraction, forward modeling, LSQ inversion, parameter models, resolution
A Study of the Effect of Thermal Annealing on the Morphology of Copper Foils as Catalyst for Graphene Growth
Full text linkTelah dilakukan penelitian tentang pengaruh “thermal annealing†terhadap morphology pada tembaga (Cu) sebagai katalis penumbuh graphene.Penelitian ini bertujuan untuk menemukan suatu kondisi optimal untuk mempersiapkan katalis tersebut pada penumbuhan graphene.Dalam penelitian ini, foil tembaga telah diteliti dengan memvariasikan suhu annealing, waktu annealing dan laju gas hydrogen. Dari hasil penelitian didapatkan bahwa kondisi optimal adalah annealing pada suhu 900 oC selama 10 menit dengan laju aliran hydrogen sebesar 100 sccm. Selain itu, penelitian “pre-thermal annealing†telah juga dilakukan untuk menguji perubahan sifat-sifat struktur dan morphology tembaga tersebut.Dari hasil penelitian ditemukan bahwa tembaga tersebut memiliki “nanocrystalline cubic structure†yang baik, di mana didominasi oleh (100) dengan ukuran crystal ~200 nm.Penelitian ini juga menunjukkan bahwa gas hydrogen efektif dalam mereduksi impurity dari oksidasi tembaga.Dan juga, annealing pada suhu 900 oC ke atas, sampel tersebut memiliki morphology yang halus pada seluruh permukaannya dan grain-grain berukuran ~ 88 µm. Kata kunci : Foil tembaga, Thermal annealing, Ukuran crystal,  and Ukuran grain
Groundwater investigation Geolistrik Methods In Regional District of Parigi Parigi Moutong
Full text linkThe research of groundwater investigation conducted by applying the method of geoelectric in the District Parigi Parigi Moutong. Identification of the substance of the study, conducted by survey / observations and measurements in the field.Field measurements using elektrical Vertical Sounding (VES) with Schlumberger electrode configuration. The results obtained indicate that the groundwater aquifer layer in the study area are the two lithologies are lithologies alluvium and coastal sediment and rock units molasa celebes. In the alluvium and coastal sediment units are at least 3 layers of the aquifer from surface to a depth of ± 25m bmt where perlapisannya alternating with layers aquiclude. Distribution of the aquifer layer on a flat stone units tend to follow the surface topography. In lithologies molasa celebes obtained their aquifer layer that is as aquifer (+). The upper limit of this layer is at a depth ±24.6m bmt decreases eastward at a depth ±40.2m bmt. The thickness of this layer is the average ±42m. allegedly sumurbor positive groundwater measuring point 16, 17 are located in the region kampal, 23 (Maesa), 24 (Mertasari), 30 (Bambalemo) and 35 (Maesa Coast) derived from this aquifer layer. Parigi district region is an area of discharge (discharge area), while the catchment area (recharge area) is located in the west area of research. Keywords: groundwater, geoelectric method, the method vertial Eletrrial Sounding, Schlumberger configuratio
Plant Watering System Design Using Soil Moisture Automatic Sensor Microcontroller Based Sen0057 ATmega328P
Full text linkIt has been designed and created a plant watering system that is expected to help watering plants from a manual system to an automated system. The watering system is designed for watering plants at the right time and humidity. This tool utilizes SEN0057 soil moisture sensors to detect the level of soil moisture and ATmega328P microcontroller as the main controller. This tool is also used as a stop relay contact or disconnect from the current to flow to the pump, the LCD to display the time and the level of soil moisture and pump to drain the water. The working principle of this device when the sensor detects kelambaban ground level is less than the pre-defined limit, the microcontroller will command the process of watering until the soil moisture value equal to or greater than the pre-defined. Pepper plants as objects of research have suitable soil moisture ranging from 50% - 60%. Thus limits for soil moisture for plant watering is 3:38 volts. Watering the plant is operated at 5:45 pm and 17:45 pm.Keywords: Soil Moisture Sensor SEN0057, ATmega328P, Relay
Determination ofCoherenceandPhaseDifferencebetween Wind versus Current60 mand Current 60 mversusCurrent 100 mUsingCrossCorrelation in OmbaiStrait, East Nusa Tenggara
Full text linkAbstract  Data analysis was performed to see coherence and phase difference between the wind versus current 60 m and current 60 m versus current 100 m using cross correlation in Ombai Strait, East Nusa Tenggara. Velocity components U and V of wind and current of wind data and the current were filtered in order to obtain new data on the initial data at any position of t from xt-n to xt+n. Energy spectrum density of the filter result is determined to examine the fluctuations of wind energy and real currents. Cross-correlation between wind versus current 60 m and current 60 m versus current 100 m is to determine the coherence and the phase difference of the data with the same time interval. Low coherence values in the cross-correlation between the Zonal Wind and the Zonal current at a depth of 60 m indicates that the fluctuations between the Zonal Wind and the zonal current depth of 60 m does not have a strong correlation with the largest coherence value that is 0.55 with a time leg 34 days. With fluctuation current at a depth of 60 m precedes wind fluctuation with a phase difference of 34 days. Keywords: coherence, phase difference, Ombai Strai