This study used fractional distillation to separate citronellal and geraniol from citronella (Cymbopogon winterianus) essential oil to improve their market value. The one-factor-at-a-time methodology investigated operating parameters’ optimum conditions and effects, including system pressure, packing types, and column height. All investigations were evaluated based on their main fraction’s citronellal and geraniol content and recovery. Regarding the effect of the variables, a higher system pressure improved the separation while increasing the temperature range of each fraction and distillation time. The packing types would also improve the separation by providing a large surface area. Finally, the column height also positively impacted the separation. In the optimum citronella oil fractionation, citronellal content experienced a 2.5-fold increase, from 37.68% to 94.33%. Geraniol purity reached 40.61% from an initial content of 17.33% in the raw CW oil. The distillation could recover up to 90.00% of citronellal and 68.18% of geraniol.
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With the growth of data stored in cloud, data may become the target of attackers in the Internet. Therefore, the end users require high confidentiality, integrity and authentication in order to protect their data in cloud. In this paper, we aim at a comprehensive studying about the data security in cloud computing. The paper will discuss the details of cloud computing data security challenges and find out which are the most important challenges as well as the efficient solutions. The existing authentication and encryption algorithms are compared in terms of users' scenarios, outstanding features and the limitation. We also review the advantages and drawbacks of the algorithms for data security in terms of cloud computing services.
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