137 research outputs found
Rain Effect Frequency of Infiltration Rate and Infiltration Capacity in Common Soil: Laboratory Test with Rainfall Simulator
Analyzing the Influence of Rain Frequency Infiltration Rate and Infiltration Capacity in Common Soil Type (Laboratory Testing Study With Rainfall Simulator). Infiltration is the flow of water into the ground through the soil surface. This process is a very important part of the hydrological cycle and in the process of transferring rain into the flow of water in the soil before reaching the river. Infiltration (infiltration rate and capacity) is influenced by various variables, including soil type, slope inclination, density and type of vegetation, soil moisture content, and rainfall intensity. This study aims to determine the effect of rainfall frequency on the infiltration rate and infiltration capacity on common soil types. This research is a type of laboratory experimental research, using rainfall simulator tool. The soil used in this study is common soil type. Furthermore, artificial rain was provided with intensity I5, I15, and I25 and performed infiltration rate reading on the Drain Rainfall Simulator. The rate and capacity of infiltration in common soils increase proportionally to the increased intensity of rainfall, the higher the intensity of rainfall the higher the infiltration occurring at the same level of rain frequency. The rate and capacity of infiltration in common soils decrease proportionally to the increasing frequency of rain, the more the frequency of rain the smaller the infiltration occurring at the same level of rainfall intensit
Efek Penambahan Epdm pada Karet Alam terhadap Sifat Mekanik Karet Busa
Penelitian ini bertujuan untuk mempelajari sifat mekanik karet busa yang dihasilkan dari campuran karet sintetis ethylene propylene diene monomer rubber dengan karet alam SIR-20. Penelitian ini dibatasi pada tiga perlakuan dengan rasio campuran karet sintetis 0 phr; 2 phr; 4 phr, karet alam 100 phr; 98 phr; dan 96 phr. Natrium hidrokarbonat, fly ash dan bahan proses lainnya dikondisikan. Banyaknya busa yang terbentuk secara kualitatif digambarkan oleh nilai specific gravity terendah. Pengujian sifat mekanik seperti compression set, tear strength, tensile strength, dan elongation at break pada penelitian ini sebagai parameter pendukung. Hasil pengujian specific gravity terendah diperoleh dari perlakuan A yaitu 1,169 g/cm3. Hasil pengujian compression set 39,88%, tear strength 20,8 kN/m, tensile strength 14,8 MPa dan elongation at break 680%. Nilai specific gravity terendah pada perlakuan A secara kualitatif menggambarkan busa yang terbentuk lebih banyak dari perlakuan yang lainnya. Penelitian ini bertujuan untuk mempelajari sifat mekanik karet busa yang dihasilkan dari campuran karet sintetis ethylene propylene diene monomer rubber dengan karet alam SIR-20. Penelitian ini dibatasi pada tiga perlakuan dengan rasio campuran karet sintetis 0 phr; 2 phr; 4 phr, karet alam 100 phr; 98 phr; dan 96 phr. Natrium hidrokarbonat, fly ash dan bahan proses lainnya dikondisikan. Banyaknya busa yang terbentuk secara kualitatif digambarkan oleh nilai specific gravity terendah. Pengujian sifat mekanik seperti compression set, tear strength, tensile strength, dan elongation at break pada penelitian ini sebagai parameter pendukung. Hasil pengujian specific gravity terendah diperoleh dari perlakuan A yaitu 1,169 g/cm3. Hasil pengujian compression set 39,88%, tear strength 20,8 kN/m, tensile strength 14,8 MPa dan elongation at break 680%. Nilai specific gravity terendah pada perlakuan A secara kualitatif menggambarkan busa yang terbentuk lebih banyak dari perlakuan yang lainnya
Adsorption Isothermal Methane Gas with Mass Flow Rate of 10 SLPMand 20 SLPM for Adsorbed Natural Gas Storage
The increase energy needs along with the times resulted in the availability of energy derived from fossil fuels thinning. Utilization of natural gas as a potential replacement for fossil fuels because of national gas production shows increase.Natural gas as a replacement for fossil fuels constrained in the storage process, storageis oftenusediscompressed natural gas(CNG) andliquefied naturalgas(LNG). CNG storage constrained at high pressure (20 MPa) and LNG constrained in gas liquefaction process that requires extremely low temperatures (-161.5°C).Adsorbed natural gas (ANG) is a solution to reduce the pressure in the tube of about 3,5 to 4 MPa by utilizing the process of adsorption using activated carbon.Adsorptionmeasurement use volumetric method (isothermal) at temperatures 25oC with 10 bar pressureand variation of the mass flow rate (10 standard liter per minute and 20 standard liter per minute).The purpose of this study was to obtain data of methane (CH4) stored and out (stuck) on the storage and also to see temperature phenomena that occur in storage.From the test results, the massof methane storedat10SLPMis33,19gram and20SLPMis43,63gram.As for themethanegasthat isstuckat10slpm is7,09gramand20slpmis16,54369gram
Simulasi Cfd Ang Storage dengan Metana sebagai Adsorbat dan Karbon Aktif sebagai Adsorbennya
Increased air pollution and fuel price volatility to the attention of the world that began to study alternative energy sources. Natural gas is an alternative that can replace fuel, natural gas used was methane. There are 3 natural gas storage process LNG, CNG and ANG. LNG requires extremely low temperatures to liquefy the methane gas whereas CNG requires a very high pressure of 200 bar for storing methane, both of these processes require a very expensive cost, whereas ANG only requires a pressure of 4 bar for storing methane so that ANG is an excellent alternative possible. ANG process has been studied experimentally, while the simulation is still very rare. This study uses the simulation computational fluid dynamics (CFD) for the ANG. This modeling using Fluent. From this simulation can be obtained the distribution of temperature, pressure, adsorption capacity and adsorption rate of capacity during the adsorption process occurs. The study was conducted at a pressure of 30 bar and a temperature of 300 K, in order to obtain the result of pressure and temperature distribution are influenced by the UDF equation source terms and methane gas adsorption capacity at the time of 54000 seconds is 0.069797 kg/kg, and the rate of adsorption at the time of 54000 seconds is 5.1x10-9kg/kg.s
Pembuatan dan Karaktrisasi Karbon Aktif Berbahan Dasar Cangkang Sawit dengan Metode Aktivasi Fisika Menggunakan Rotary Autoclave
Activated carbon is an absorbent that has widely used because it's high absorption capacity. Necessity to improve the quality of activated carbon made from palm shells with low price and easy to obtain. The process of preparation and characteristics of activated carbon conducted in this research using physical activation using CO2 as the activating agent. Carbonization and activation processes performed in a rotating furnace (rotary autoclave) by flowing nitrogen gas (N2) at 100 ml/min and CO2 flow rate of 250 ml/min. Carbonization temperature 500oC was used with some variation of carbonization time, activation time and activation temperature. The results seen with activated carbon characteristics knowing iodine numbers obtained from any activated carbon produced. Optimum characteristics of activated carbon obtained by activation at 750oC temperature, the duration of carbonization and activation of activated carbon produced during 2 hours with 603 g / kg of iodine number
“The Spirit of Turbulence”: East Indian Political Imaginaries in Early 20th Century British Guiana
After the abolition of slavery, the Colonial Office instituted an indentured labor scheme that lasted from 1838 to 1917, in which they brought East Indians to the plantation colonies as laborers under five year contracts. Due to the planter class’ desire for permanent sources of labor in British Guiana, the Colonial Government incentivized East Indians to permanently settle. East Indians thus dominated the British Guiana’s agricultural landscape and became the single largest ethnicity in the Colony by 1920. This thesis explores the early negotiations of the meaning of diaspora and diasporic citizenship for East Indians in British Guiana. They comprised a diverse conglomerate of different socio-economic positions: agricultural estate laborers, village residents, and middle-class business professionals. Each socioeconomic group had a different lived experience in the colony and different outlook on what it meant to be a creole-born East Indian. This thesis traces the multiple and contingent ideas of citizenship and nationality that were circulating at the time. Against a backdrop of changing imperial politics that promoted modernity and the discourse of the nation, East Indian visions centered around how to construct permanence, and negotiate belonging. By drawing on colonial documentation–local reports, commission transcripts, personal correspondence–and documentation produced by East Indians–memorandums, speeches, and books–this thesis ultimately argues that East Indians came to view culture as integral to their self-worth and definitions of place within the imperial system. Culture thus became the primary lens to negotiate the various meaning of citizenship and place in the imperial-national moment
Adsorpsi Isothermal Hidrogen pada Karbon Aktif Berbahan Dasar Cangkang Sawit pada Temperatur 45 OC
Hydrogen is one of the promising renewable energy and potential subtitute for fossil fuels in the future. Hydrogen has short comings in its application as fuel is in storage. The study resulted in the capacity of hydrogen adsorption on activated carbon made from palm shells. Data were collected by volumetric method in the isothermal adsorption process. Adsorption isotherm temperature is performed at 45oC at pressures up to 30 bar. The maximum adsorption capacity at isotherm temperatures 45oC is 2.03x10-3 kg/kg mass of adsorbent at a pressure of 30.13 bar. Subsequently correlated the data obtained using the Langmuir model equation, Toth and Langmuir-Freundlich. Deviation from the Langmuir equation, Toth and Langmuir-Freundlich obtained was 16.72.77%, 15.97% and 9.79%
Permukiman di Indonesia: perspektif arkeologi
Menggali masa lalu (digging up the past) merupakan tugas para ahli arkeologi untuk mengungkapkan gagasan, perilaku dan karya-karya leluhur kita yang sarat dengan makna dan nilai, untuk selanjutnya diberikan kepada generasi sekarang dan yang akan datang. Banyak hal yang dapat dipelajari dari peninggalan budaya masa lampau. Buku ini merupakan langkah kecil untuk menghantarkan beberapa hal kebudayaan masa lampau berdasarkan hasil-hasil penelitian arkeologi kepada masyarakat luas
Adsorpsi Isotermal Co2 Bertekanan Tinggi Pada Karbon Aktif Dengan Metoda Volumetrik
High Pressure Adsorption Isotherm of CO2 on Activated Carbon using Volumetric Method. Adsorption system is ones of the most effective methods for CO2 separating with other substances that produced from the burning of fossil fuels. In the design for that application, beside of characteristics of porous material (adsorbent) data, CO2 adsorptiondata on the adsorbent (kinetic and thermodynamic) are also needed. The aim of this research is resulting isothermal adsorption data at pressures up to 3.5 MPa by indirect methods (volumetric method) at isothermal temperature of 300, 308, 318 and 338 K. Adsorbent that used in this research is activated carbon made from East of Kalimantan coals byphysical activation method (CO2) which is the surface area of activated carbon is 668 m2/g and pore volume is 0.47 mL/g. Carbon dioxide (CO2) that used in this research is high purity carbon dioxide with a purity of 99.9%. Data from the experiment results then correlated using the Langmuir and Toth equations model. The results showed that the maximum adsorption capacity is 0.314 kg/kg at 300 K and 3384.69 kPa. The results of regression of experiment data using Langmuir and Toth models were 3.4% and 1.7%
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