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Papers by Cemil koyunoğlu

Interdisciplinary Applications of the Life Cycle Assessment Tool, 2021

Advances in Energy and Power, 2017

Journal of Biochemistry and Analytical studies, 2020

Algal Biotechnology for Fuel Applications

It is well known that the use of algae-based fuels is not widespread as theydo not meet the neces... more It is well known that the use of algae-based fuels is not widespread as theydo not meet the necessary fuel standards. The amount of oil products obtained fromtraditional biomass sources exceeds that obtained from algae. However, ecology canprovide more assistance in increasing the current efficiency of oil production fromalgae. Depending on the species, effective results can be obtained through theproduction of fatty acids and biofuels. The amount of fuel produced by a single speciesshould be weighted against the amount of oil produced by a combination of species.The presence of genetic diversity, particularly in two types of algae mixtures, isunavoidable in order to improve the quality of fuel produced. The lipid obtained undergenetically diverse population is highlighted in this study.

Algal Biotechnology for Fuel Applications

CO2, which is a gas produced as a result of combustion, has an importantshare in greenhouse gases... more CO2, which is a gas produced as a result of combustion, has an importantshare in greenhouse gases such as SOx, CO, and NOx and causes global warming. Asbiodiesel produced from algae converts CO2 within the biological carbon cycle, itaccelerates the carbon cycle, as a result of which the greenhouse gas effect decreases.C16-C18 methyl esters in biodiesel whose degradability feature resembles dextrose(sugar) do not show any negative microbiological affect up to 10000 mg/L, theydecompose rapidly in nature. 40% of diesel in water and 95% of biodiesel in 28 dayscan be degraded. In the production of biodiesel, catalysts that break the triglyceridebonds allow the esters to become free.

Cleaner Chemical Engineering

Algal Biotechnology for Fuel Applications

In order to better evaluate the water potential of our world, we will now takea look at the vario... more In order to better evaluate the water potential of our world, we will now takea look at the various aquatic products that have had a significant impact on the biotechindustry, from research materials to nutritional additives.

Clinical Medical Reviews and Reports, 2020

The functions of existing proteins are explained based on the proteins of previously known corona... more The functions of existing proteins are explained based on the proteins of previously known coronaviruses. While the role of most non-structural proteins in viral replication has been defined, the role of some is still not fully explained. Four structural proteins have an essential role in combining virion and being a target for coronavirus infection pathogenesis and drug development.

Fuel

Abstract Dimethyl ether (DME) is one of the most sought-after automotive fuels. Catalyst is gener... more Abstract Dimethyl ether (DME) is one of the most sought-after automotive fuels. Catalyst is generally preferred in direct dime production from synthesis gas. 0In our study, Computational Fluid Dynamics is used for reactor modeling of DME production from syngas in a fluid bed model. It is aimed to determine the necessary conditions to ensure maximum gas-solid contact for the production of zeolite-catalyzed DME in a fluidized reactor, especially for the syngas produced by gasification method from domestic wastes. A distinctive feature of this approach is the physical optimisation simulation. The calculation of the bed density at which the catalyst active surface is provided at maximum contact has a very important place in determining the reactor operating conditions. In the study, firstly, the simulation model is compared with a real experimental fluidized bed model. In the subsequent optimization study, the conditions where the maximum solid-gas contact surface was achieved was sought. For this reason, the results obtained in the case of a bed density of 2200 kg/m3 showed that the pressure drop increased positively across the bed. This means that the reaction time is reduced. Therefore, the bed density value of 2200 kg/m3 (with a maximum volume fraction of 55%), is the ideal density value to ensure maximum gas-solid contact compared to 2300 (with a maximum volume fraction of 55,8%), 2400 (with a maximum volume fraction of 59,5%), 2500 (with a maximum volume fraction of 58,9%), and 2600 (with a maximum volume fraction of 57,2%) kg/m3.

Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2018

Uluslararası Yakıtlar Yanma Ve Yangın Dergisi, 2021

Journal of the Institute of Science and Technology, 2021

In this study, the performance of different refrigerants (with low GWP value) depending on thermo... more In this study, the performance of different refrigerants (with low GWP value) depending on thermophysical properties in the cooling system was evaluated. The cooling capacities of R134a, R445a, R515a, R456a, ND, and R516a refrigerants used in the cooling system are determined per unit refrigerant. If the compressor speed values and the volumetric efficiency of the compressor are constant, the results of the effects of the refrigerants in the cooling system are compared with each other. When the system is operated with R445a, the highest COP value is obtained when the volumetric efficiency value is 0.7. The R515a provided the closest COP value to R134a when the compressor speed was 1750 rpm and the 98% coefficient of performance value was similar. When the refrigerants considered are evaluated together, it was determined that R445a provides the best values according to R134a and has an average cooling capacity of approximately 12% is higher.

In this study, the ignition delay measurement determined numerically by using some practical equa... more In this study, the ignition delay measurement determined numerically by using some practical equations. Outboard ignition engines take the fuel-air mixture into the cylinder and compress it. High compression ratio is an important parameter that increases engine efficiency. The compression ratio is kept away from the knock limit, which is also defined by self-ignition of the mixture. The ignition system should be able to initiate combustion without igniting the mixture at the appropriate moment and causing undesired mechanical and thermal stresses. The temperature at the tip of the spark plug at the time of ignition is proportional to the blur of the gauge voltage and usually ranges from 500-800 o C. A well-working flue gas should have a porcelain temperature of less than 500 o C and no more than 850 o C. The temperature at the end of the isolator is crucial for the development of ignition and combustion. Higher tip temperatures, premature ignition, and low temperatures cause spark p...

SSRN Electronic Journal, 2021