Seyyed Bagher Mortazavi, Mehdi Salari, Hasan Asilian Mahabadi, Rostami Aghdam Shendi Maryam, Mohammad Miri, Mohsen Yazdani Aval,
Volume 28, Issue 166 (11-2018)
Abstract
Background and purpose: Styrene, one of the most important compounds of VOCs, causes some health concern. In current study, the ability of ZSM5, TiO2/ZSM5, UV/ ZSM5, and UV/TiO2/ZSM5 methods was investigated in removing styrene from air synthetic current.
Materials and methods: In order to synthesize the zeolite and TiO2-coated zeolite, the sol-gel and saturation methods were employed, respectively. In this study, the effect of the type of removal process, saturation time and initial pollutant concentration were investigated on the removal of styrene in a photoreactor. Phocheck device with direct reading system was applied to determine the output concentration. Also, SEM, XRD, EDX, and BET analyses were used to characterize the chemical and physical properties of ZSM5, and TiO2/ZSM5.
Results: SEM analysis showed that zeolite has a crystal form, and TiO2 successfully covered the surface of this compound. In addition, the EDX analysis demonstrated that a great part of zeolite structural includes Al and Si constituents. The XRD pattern showed the presence of attached TiO2 in the zeolite structure. BET analysis revealed that the surface area of zeolite decreased when TiO2 was coated on its surface. The order of increase in removal efficiency was as follows: UV/TiO2/ZSM5 > ZSM5> TiO2/ZSM5. The saturation time of ZSM5 and TiO2/ZSM5 in the 300 ppm concentration was 370 and 280 min, respectively, while the outlet concentration in the UV/TiO2/ZSM5 method was fixed at 74% removal efficiency after elapsing 310 min. The increment of time exposure and initial styrene concentration also led to decrease in removal efficiency.
Conclusion: In this study application of UV/TiO2/ZSM5 process provided a higher efficiency of the styrene removal than that of TiO2/ZSM or ZSM5 in the same time.
Seyyed Reza Hashemi, Ramezan Ali Ataee, Gholam Hossein Alishiri, Mahdi Ghorbanalizadegan, Mostafa Mahabadi, Ali Najafi,
Volume 29, Issue 173 (6-2019)
Abstract
Background and purpose: Etiology of rheumatoid arthritis is not fully recognized. The purpose of this study was to use universal and specific primers to trace bacteria in the blood and synovial fluid in patients with rheumatoid arthritis.
Materials and methods: In this experimental study, a PCR method was developed to identify a wide range of bacteria in general and Staphylococcus aureus in specific. Ninety five synovial fluid and 100 blood samples being stored at -80°C were assayed. Genome extraction was performed. Universal primer pairs were used for amplification of 16SrRNA and a specific primer was used for nuc gene of Staphylococcus aureus. Then, the PCR product of the specific primer was sequenced and data were analyzed.
Results: The samples of synovial fluid and blood samples of rheumatoid arthritis patients which were negative in bacteriological culture showed 33 (34%) and 36 (36%) cases to be positive for 16Sr RNA, respectively. Also, 21 cases of synovial fluid and only 1 blood sample were positive for Staphylococcus aureus.
Conclusion: The results showed the presence of 16SrRNA gene of different bacteria, including Staphylococcus aureus in blood and synovial fluid of patients. Based on current findings, it is likely to explain a part of the etiology of rheumatoid arthritis, thereby modifying some treatment protocols.
