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The addition of Effective Microorganims 4 (EM-4) activator against the biogas production was done to utilize the tofu industrial wastewater as one of the substrate for biogas production so it can increase its economic value. The aim of this research was to determine the optimum EM-4 concentration as a biogas activator using tofu industrial wastewater as a substrate. This research was conducted by adding the EM-4 activator with different concentrations of 0.25%, 0.50%, 0.75%, and 1% into the 20 litre of tofu wastewater substrate. The process of biogas formation was observed through a pressure reading on pressure gauge tools on digester. The burning of biogas is done after the presure became constant. The optimal EM-4 activator addition for 20 litre of tofu wastewater substrate was 0.75%, with burning time is 14 minutes 56 seconds.

Global warming is causing an increase in temperature of the earth's atmosphere, climate change, resulting in the dry season and rising temperatures. Efforts to control global warming is with the plant the absorption of carbon. One of which is rubber plant that has a high potential carbon reserve. The purposed of this researched was to know the carbon content in each section rubber tree (Hevea brasiliensis Muell. Arg.) and determined the potential of carbon reserved in the rubber tree (Hevea brasiliensis Muell. Arg.) Age of 5 years in people plantation Serdang Bedagai. The method of estimaty carbon stocks done destructive and selection of plant samples carried out with purposived sampling. The carbon content in each section rubber trees (Hevea brasiliensis Muell. Arg.) 5 years of age is different is stem 50.37%, 40.58% branches and leaves 21.68%. The results showed that allometric models for biomass and carbon has W = 0,540 H1.882 and C = 0.053 H 2.526 . The potential of biomass and carbon in smallholder rubber plantations Tarean Village, District Silindak, Serdang Bedagai well 2.71 tons / ha and 1.18 tons / ha. 111201127

Bioethanol is one type of biofuel that developed significantly. The utilization of bioethanol is not only limited for fuel, but also could be used as material for various industries such as pharmaceuticals, cosmetics, and food. With wide utilization and relatively simple production technology has made bioethanol as the most favored biofuel currently. The use of lignocellulosic biomass, microalgae, seaweeds, even GMO (Genetically modified organisms) as substrates for bioethanol production has been widely tested. Differences in the materials eventually led to change in the production technology used. Pretreatment technology in the bioethanol production using lignocellulosic currently experiencing rapid development. It is a key process and crucial for the whole next steps. Based on the advantages and disadvantages from all methods, steam explotion and liquid hot water methods are the most promising pretreatment technology available.

Nowadays the use of cooling engine with refrigerant as its cooling source used by most people, but the use of these refrigerants such as CFCs and HFCs can cause thinning of the ozone layer in the atmosphere and also cause the greenhouse effect. Thermoelectric coolers can be used as a main source of alternative coolers that people needed. One example is the use of cooling box. The purpose of this study was to examine and analyze the cooling load in the cooling box that uses thermoelectric with energy came from photovoltaic. The study was done by using an experimental method in which the cooling box that has been designed, tested to determine the temperature inside the box by using a thermocouple. Other parameters such as Relative Humidity, Intensity of solar radiation, Dew-point Temperature were measured using HOBO data logger. Parameters that have been obtained then processed and calculated using mathematical equations to obtain the cooling load inside the cooling box. This study focused on the calculation of the efficiency of the photovoltaic, the calculation of the coefficient of performance of thermoelectric, the calculation of the capacity of battery to store energy, and analyze the cooling load. The analysis showed that the average cooling load in the cooling box with five 240 ml mineral water is 126,94 Watt, efficiency of photovoltaic is 15,57%, coefficient of performance of thermoelectric is 0,754 and the coefficient of performance of the system in cooling box is 0,225 100401033

Bioethanol is one kind of renewable energy which is being improved in the world to fulfill the demands of energy consumption. Bioethanol which was produced in this research used the hydrolysate of husk cacao waste. The husk cacao is solid waste plantation which is abundant and hasn’t yet had an amount of usings. The purpose of this research is knowing the effect of the quantities of bread yeast used in this research to the length of days fermentation and producing bioethanol got from the hydrolysate of husk cacao waste by using fermentation process added with tannin as preventive oxidation in bioethanol such as formation of acetate acid, and using bread yeast as the source of microorganism to convert into bioethanol. The main substances are the hydrolysate of husk cacao waste produced from acid hydrolysis process using sulphate acid 4 M during two hours at 100 oC degree, tannin, and bread yeast. Afterwards the hydrolysate was fermented in variation sums of bread yeast 3%, 5%, and 7% (w/w) and added with gambier as tannin source in 2, 3, 4, and 5 days and then the hydrolysate was distilled at 80 oC degree by using rotary evaporator having trade mark Ruchi Evaporator R-205. The result of this research indicated that the fermentation process produced bioethanol. The quantitative analysis used GC instrument and the largest content degree of bioethanol was 99,8174% in amount of bread yeast 3% (w/w) in the third day of fermentation and the largest yield degree of bioethanol was 34,4483% in amount of bread yeast 5% (w/w) in the fifth day of fermentation. The qualitative analysis used refractometre having trade mark ABBE to examine refractive index by choosing the sample having the largest content degree of bioethanol and the result was 1,3285 100405045

Bioethanol is one kind of renewable energy which promises in this world. The energy source of bioethanol can be got from plantation wastes which are scarecely useful such as husk cacao waste. The purpose of this research is knowing the ratio effect of solid : water and the concentration of catalyst about the gain of the degree of reducter sugar from husk cacao powder. The main substances used in this research are husk cacao wastes from cacao plantation and sulphate acid. The variables used in this research are the ratio of solid : water and the concentration of catalyst in hydrolysis process. The husk cacao which had been dried by sun light were milled in a ball mill, filtered by strainer 100 mesh, added with sulphate acid catalyst which had concentration 2 M, 3 M, and 4 M, and afterwards done hydrolysis process by using hot plate. The hydrolysis process took at 100 oC degree and two hours and then the hydrolysates were analyzed in quantitative and qualitative. The result of this research indicated that the hydrolysate of husk cacao contented reducted sugar.which can be used as the main substance to produce bioethanol. The quantitative analysis about reduction sugar degree indicated the reducted sugar degree increased as many as the catalyst concentrations and had reverse proportion with the main substance ratio. The best reducted sugar is 30,67% which was produced at at 100 oC degree in 120 minutes by using ratio between solid : water was 1 : 5 and catalyst concentration was 4 M 100405060

Common problems facing the world at the present time is the depletion of petroleum reserves and negative impacts of the use of fuel oil. This phenomenon prompted us to look for alternative fuels that can solve both problems at the top, in this case the gas fuel is biogas. This study aims to analyze the performance of the diesel engine designed R175AN TIGER system uses two fuel (dual fuel) diesel and biogas results of palm oil waste to methane content of 70% to produce electricity as well as the addition of catalytic converters in the hope of reducing exhaust emissions. Maximum power is obtained on the use of pure diesel + 4 l / min for 1381.76 biogas Watt, maximum torque occurs in pure diesel + 4 l / min biogas, amounting to 8.8 Nm at 1500 Watt load rotation 1500 rpm, maximum SFC occur on materials diesel fuel loading 600 Watt 1000 rpm rotation of 875.29 g / kWjam, AFR value at solar maximum + 6 l / min biogas load 600 Watt 292.37 rotation of 1000 rpm, the maximum thermal efficiency in solar + 6 l / min for biogas 45.26% at 1000rpm rotation load of 600 Watt, the average effective pressure occurs at solar maximum of + 4 l / min biogas loading 1200 Watt 1500 rpm rotation of 312.93 kPa, the largest opacity on the use of diesel + 2 l / min biogas in 1500 watt load 1500 rpm rotation by 31%. Levels of HC (Hydro Carbon) and CO (Carbon Monoxide) decreased when using catalytic converters. By using biogas can save the economic value of solar 100401108

Dolly Sojuangan Siregar: Inventory of degredation level and carbon stock in protected mangrove forest Kuala Langsa, Aceh. Supervised by Mohammad Basyuni and Siti Latifah. The purpose of this study was to find out accurate data on mangrove species diversity, carbon stock and level of degredation of protected mangrove forest Kuala Langsa which refers to the Guidelines for Identification of Critical Areas Inventory and Mangrove Department of Forestry Directorate General of Land Rehabilitation. A research location in Kuala Langsa Mangrove Forest is geographically located at 97º 53 '15 "- 98º 04' 42" East longitude and 04º 24 '35 "- 04º 33' 47" North Latitude. The survey used to inventory mangrove forest is purposive random sampling method, taken random starting from the sea front towards to the deepest zone. Vegetation study using 3 plots containing 14 lines with a width of 20 m to 190 m length of the line, the distance between plots was 10 m. Measurements made of the tree was a woody plant with Ø ≥ 10 cm (20 m x 20 m), saplings were higher than 1,5 m up to Ø <10 cm (5 m x 5 m), and seedlings were to as high as 1,5 m (2 m x 2 m) Results of this study showed that Rhizophora apiculata dominated either type of seedlings, saplings and trees with the number density of seedlings were 11011,90 individuals/ha, density of saplings were 3009,52 individuals/ha, and density of tree were 70,83 individuals/ha. Total tree biomass was 19.062,68 kg/ha, with carbon stocks of 9,53 tons/ha. Total value score criticality level of protected mangrove forest Kuala Langsa was 285(standard value of non degraded was < 300) resulted this area was degraded. 107001015

Due to the decreasing of fosil fuel resources which encourage us to do the research and development of alternative fuels. One of the alternative fuels resources is using sesame seeds (Sesamum Indicum L) to produce biodiesel. This study aims is to analyze the performance of TD - 115 diesel engine using sesame seeds biodiesel mixture of 5 % , 10 % , 15 % and 20 % . The test results indicate that Calorific Value (CV), engine rotations (rpm) and Load (W) given affects the amount of Torque (T) and so the Power (P) decrease up to 36,44 %, while Specific Fuel Consumption (SFC) of the mixture increase up to 148 %, Volumetric Efficiency ( ) decrease up to 16,52 %, Thermal Actual Brake Efficiency ( decrease up to 56,74 % and Heat Losses decrease up to 35,01 %. 110401061

Medan city is located in IMT-GT (Indonesia-Malaysia-Thailand Growth Triangle ) strategic position and included as one of the National Strategic Area. This situation motivates Medan city to be improved into an ideal city. Through the cooperation of Mebidangro (Medan-Binjai-Deli Serdang-Karo), it is expected to create more ideal city and generalize population distribution. By creating ‘magnet’ on the subburbs is a method to attract people to move to new areas. Green Deli Oasis become the ‘magnet’ in north of Medan,and is a renewal of Pulo Brayan cultural areas. GDO Expo and Convention Center is one of the buildings in that area, the building is aimed to be a generator public activities in terms of meetings, conventions, exhibitions and other activities that are visited by many people at one time in the same place. The excessive energy usage is one of global warming causes, thus the energy efficient architecture theme is chosen as the design theme to work out this issue.. Methods which are done in this design process of GDO Expo and Convention Center are literature studies to get an explanation of the design as well as reference / comparisons in the design and field studies to collect necessary physical data. In addition to these studies, interviews and discussions with designrelated- person are also conducted. GDO Expo and Convention Center can be visited 4,000 to 8,000 people for a historical tour activity. Energy efficient architecture theme can applied to the building by utilizing the sun as sources of natural lighting and a solar power, the wind as a natural air conditioning to reduce the usege of air conditioning tools, and rainwater as building water supply. As a result,the building is fungtional, has an attractive visual and can saves energy by utilizing the climates. 120406023