Removal of hydrocarbons from wastewaters

Thesis (Master)--Izmir Institute of Technology, Environmental Engineering, Izmir, 2002Includes bibliographical references (leaves: 68-72)Text in English; Abstract: Turkish and Englishx, 72 leavesWastewater of chemical industries and petrochemical spills are the main sources of hydrocarbon pollution. Benzene, toluene and o- xylene are generally found in petrochemical spills which effect the all livings in the environment because of its toxicity.This thesis was an investigation of benzene, toluene and o- xylene (nonpolar aromatics) adsorption on clinoptilolite rich natural zeolite and surfactant modified zeolite. The aim of surfactant modification was to make highly polar zeolite surface hydrophobic and thereby remove the hydrophobic benzene, toluene and o- xylene molecules from the aqueous phase with the help of hydrophobic attraction forces.Cationic surfactants Dodecyl Amine (DA), Tetramethylammonium (TMA+) and an anionic surfactant Sodium Dodecyl Sulfate (SDS) were used for surface modification.The degree of surface hydrophobicity was examined by calculating the change in Gibbs free energy of the zeolite-water system by using the contact angle and surface tension measurement results in the presence and absence of surface modification. For natural zeolite the mean contact angle value was found 7.76o. Modification by DA and TMA+ increased .m from 7.76o to 51.13o and 29.37o respectively at a concentration of M. In case of SDS, at the pH value of 4, there was only a slight increase from 7.76 o to 18.03 o at a concentration of M. Effect of these surfactants on interfacial tension at air water interface was also different from eachother. DA decreased the surface tension from 72.8 to 37 dynes/cm while TMA+ did not bring any change. This part of the study showed that the presence of surfactant makes zeolite surface more hydrophobic.In adsorption studies, natural zeolite removed 20% of hydrocarbons from water. Except toluene, there was an optimum time that the removal was high. Presence of surfactant was able to increase this percent up to 40% under some conditions depending on the surfactant and hydrocarbon type and concentration. The highest benzene adsorption was obtained with TMA+ modified zeolite. The sequence was benzene > toluene > o-xylene. In case of DA modified zeolite, on the other hand, oxylene was adsorbed more than the other hydrocarbons. The removal follows the order o- xylene > toluene > benzene in this case

A model of distributed key generation for industrial control systems

11th International Workshop on Discrete Event Systems, WODES 2012; Guadalajara, Jalisco; Mexico; 3 October 2012 through 5 October 2012The cyber-security of industrial control systems (ICS) is gaining high relevance due to the impact of industrial system failures on the citizen life. There is an urgent need for the consideration of security in their design, and for the analysis of the related vulnerabilities and potential threats. The high exposure of industrial critical infrastructure to cyber-threats is mainly due to the intrinsic weakness of the communication protocols used to control the process network. The peculiarities of the industrial protocols (low computational power, large geographical distribution, near to real-time constraints) make hard the effective use of traditional cryptographic schemes and in particular the implementation of an effective key management infrastructure supporting a cryptographic layer. In this paper, we describe a "model of distributed key generation for industrial control systems" we have recently implemented. The model is based on a known Distributed Key Generator protocol we have adapted to an industrial control system environment and to the related communication protocol (Modbus). To validate in a formal way selected security properties of the model, we introduced a Petri Nets representation. This representation allows for modeling attacks against the protocol and understanding some potential weaknesses of its implementation in the industrial control system environment

Distributed and biometric signature-based identity proofing system for the maritime sector

The maritime sector is an industry that faces significant and various challenges related to cyber security and data management, such as fraud and user authentication. Therefore, there is a need for a secure solution that can effectively manage data transactions while resolving digital identity. A biometric signature application in blockchain for fighting fraud and fake identities may provide a solution in the maritime sector. This research proposes a biometric signature and an IPFS network-blockchain framework to address these challenges. This paper also discusses the proposed framework's cyber security challenges that threaten behavioral biometric security

An information geometrical evaluation of Shannon information metrics on a discrete n-dimensional digital manifold

The definition and nature of information have perplexed scientists due to its dual nature in measurements. The information is discrete and continuous when evaluated on a metric scale, and the Laplace-Beltrami operator and Gauss-Bonnet Theorem can map one to another. On the other hand, defining the information as a discrete entity on the surface area of an n-dimensional discrete digital manifold provides a unique way of calculating the entropy of a manifold. The software simulation shows that the surface area of the discrete n-dimensional digital manifold is an effectively computable function. Moreover, it also provides the information-geometrical evaluation of Shannon information metrics

Detecting User Behavior in Cyber Threat Intelligence: Development of Honeypsy System.

This research demonstrates a design of an experiment of a hacker infiltrating a server where it is assumed that the communication between the hacker and the target server is established, and the hacker also escalated his rights on the server. Therefore, the honeypot server setup has been designed to reveal the correlation of a hacker’s actions with that of the hacker’s experience, personality, expertise, and psychology. To the best of our knowledge, such a design of experiment has never been tested rigorously on a honeypot implementation except for self-reporting tests applied to hackers in the literature. However, no study evaluates the actual data of these hackers and these tests. This study also provides a honeypot design to understand the personality and expertise of the hacker and displays the correlation of these data with the tests. Our Honeypsy system is composed of a Big-5 personality test, a cyber expertise test, and a capture-the-flag (CTF) event to collect logs with honeypot applied in this sequence. These three steps generate data on the expertise and psychology of known cyber hackers. The logs of the known hacker activities on honeypots are obtained through the CTF event that they have participated in. The design and deployment of a honeypot, as well as the CTF event, were specifically prepared for this research. Our aim is to predict an unknown hacker's expertise and personality by analyzing these data. By examining/analyzing the data of the known hackers, it is now possible to make predictions about the expertise and personality of the unknown hackers. The same logic applies when one tries to predict the next move of the unknown hackers attacking the server. We have aimed to underline the details of the personalities and expertise of hackers and thus help the defense experts of victimized institutions to develop their cyber defense strategies in accordance with the modus operandi of the hackers

Study of CAPE effect on apoptosis induction in AGS human gastric cancer cell line

Background: Propolis is a natural product of bee and caffeic acid phenethyl ester (CAPE) is a pharmacologically important product of propolis. Objectives: The aim of this study was to investigate the effect of CAPE on apoptosis induction in AGS human gastric cancer cells. Materials and Methods: The cytotoxic effects of CAPE at different concentrations were investigated on AGS cells viability after 24 hours treatment by MTT assay. To measure the effect of CAPE on apoptosis induction, AGS cells were treated with CAPE for 24 hours and investigated by FITC Annexin V/PI staining using flow cytometry. Results: CAPE prevented growth and proliferation of AGS human gastric cancer cell line in a concentration-dependent manner with an IC50 of approximately 60 μM by a 24-hour treatment. Also CAPE caused increased induction of apoptosis in AGS cells from 1.37 % in control cells to 21.76 % in treated cells with 30 μM CAPE. Conclusions: CAPE prevents growth and proliferation of AGS human gastric cancer cell line through inducing programmed cell death in AGS cells. Therefore, CAPE could be helpful for developing chemotherapeutic agents or as an adjuvant for human gastric cancer treatment. © 2016, School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences

Karın duvarı defektlerinin fasyokütan fleplerle onarımı[Deneysel çalışma]

TEZ1108Tez (Uzmanlık) -- Çukurova Üniversitesi, Adana, 1992.Kaynakça (s. 46-50) var.50 s. : rnk. res. ; 30 cm.

Satellite Networks for Key Management

3rd International Conference on Recent Advances in Space Technologies, RAST 2007; Istanbul; Turkey; 14 June 2007 through 16 June 2007The cryptographic key management center is the place where all the cryptographical protocols and related keys are in action. Traditionally the key management centers operate on the ground. However; with the satellites, it is possible to conceive a space based key management center. This paper underlines the pros and cons of having a satellite networks key management center