Biodegradation of Crude Oil-contaminated Soil using Canned-food-industry Wastewater Sludge for Soil Application

Efsun Dindar,F. Olcay Topaç Şağban,Hüseyin S. Başkaya 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.5

The objective of this study was to evaluate the effects of crude oil (application doses of 0.5% and 5%) from hydrocarbon contamination on the removal of the Total Petroleum Hydrocarbons (TPH) from soil and to determine the removal of TPH at different temperatures (18°C and 28°C) during an incubation period of 240 days. The possible use of wastewater sludge as a biostimulating agent in crude oil-contaminated soils was also evaluated. The results of the 240 days of incubation indicated that the TPH removal percentages in crude oil-contaminated and sludge-treated soils at 18°C were 89% and 79%, for doses of 0.5 and 5%, respectively. Incubation at 28°C resulted in higher TPH removal with removal percentages of 83% (dose of 0.5%) and 91% (dose of 5%). The degradation of crude oil in contaminated soil treated with a 5% dose was significantly enhanced by the addition of wastewater sludge, whereas no apparent biostimulating effect on TPH removal was observed in the case of low-dose (0.5%) crude oil contamination.

Effect of Orifice Induced Hydrodynamic Cavitation on the Properties of Waste Activated Sludge

Esra Demir Karaçoban,Fatma Olcay Topaç,Efsun Dindar,Bülent Keskinler 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.4

Exploring alternative methods to reduce the quantity of wastewater sludge and improve its characteristics is among the prioritized subjects in the field of sludge management. Hydrodynamic cavitation, commonly employed for water and wastewater treatment, also holds the potential for utilization as a pre-treatment method for sludge. In the presented study, the excess sludge obtained from the wastewater treatment facility of a food and beverage manufacturing factory was collected and disintegrated with a orifice-induced hydrodynamic cavitation unit. According to the data obtained, the highest cavitation performance was achieved under the condition where the cavitation number was set to 0.3. In addition, hydrodynamic cavitation performed under the optimum operating conditions, significantly increased the solubility of waste activated sludge. The results showed that the soluble chemical oxygen demand concentration, which was initially determined as 382 mg/l, reached 3,068 mg/l end of the cavitation. 64% of the total Kjeldahl nitrogen and 60% of the total phosphorus of waste-activated sludge were converted into soluble forms by the effects of hydrodynamic cavitation. Moreover, the results of the microbial study indicated that removal rates of indicator bacteria varied between 94% and 99%.

High-rate Single-Frequency Precise Point Positioning (SF-PPP) in the detection of structural displacements and ground motions

Mert Bezcioglu,Cemal Ozer Yigit,Ahmet Anil Dindar,Ahmed El-Mowafy,Kan Wang 국제구조공학회 2024 Structural Engineering and Mechanics, An Int'l Jou Vol.89 No.6

This study presents the usability of the high-rate single-frequency Precise Point Positioning (SF-PPP) technique based on 20 Hz Global Positioning Systems (GPS)-only observations in detecting dynamic motions. SF-PPP solutions were obtained from post-mission and real-time GNSS corrections. These include the International GNSS Service (IGS)-Final, IGS real-time (RT), real-time MADOCA (Multi-GNSS Advanced Demonstration tool for Orbit and Clock Analysis), and real-time products from the Australian/New Zealand satellite-based augmentation systems (SBAS, known as SouthPAN). SF-PPP results were compared with LVDT (Linear Variable Differential Transformer) sensor and single-frequency relative positioning (SF-RP) solutions. The findings show that the SF-PPP technique successfully detects the harmonic motions, and the real-time productsbased PPP solutions were as accurate as the final post-mission products. In the frequency domain, all GNSS-based methods evaluated in this contribution correctly detect the dominant frequency of short-term harmonic oscillations, while the differences in the amplitude values corresponding to the peak frequency do not exceed 1.1 mm. However, evaluations in the time domain show that SF-PPP needs high-pass filtering to detect accurate displacement since SF-PPP solutions include trends and lowfrequency fluctuations, mainly due to atmospheric effects. Findings obtained in the time domain indicate that final, real-time, and MADOCA-based PPP results capture short-term dynamic behaviors with an accuracy ranging from 3.4 mm to 8.5 mm, and SBAS-based PPP solutions have several times higher RMSE values compared to other methods. However, after high-pass filtering, the accuracies obtained from PPP methods decreased to a few mm. The outcomes demonstrate the potential of the high-rate SF-PPP method to reliably monitor structural and earthquake-induced ground motions and vibration frequencies of structures.

Investigating the effects of ultra-rapid, rapid vs. final precise orbit and clock products on high-rate GNSS-PPP for capturing dynamic displacements

Cemal O. Yigit,Ahmed El-Mowafy,Mert Bezcioglu,Ahmet A. Dindar 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.73 No.4

The use of final IGS precise orbit and clock products for high-rate GNSS-PPP proved its effectiveness in capturing dynamic displacement of engineering structures caused by earthquakes. However, the main drawback of using the final products is that they are available after approximately two weeks of data collection, which is not suitable for timely measures after an event. In this study, the use of ultra-rapid products (observed part), which are available after a few hours of data collection, and rapid products, which are available in less than 24 hrs, are investigated and their results are compared to the more precise final products. The tests are designed such that harmonic oscillations with different frequencies and amplitudes and ground motion of a simulated real earthquake are generated using a single axis shake table and the PPP was used to capture these movements by monitoring timechange of the table positions. To evaluate the accuracy of PPP using ultra-rapid, rapid and final products, their results were compared with relative GNSS positioning and LVDT (Linear Variable Differential Transformer) data, treated as reference. The results show that the high-rate GNSS-PPP solutions based on the three products can capture frequencies of harmonic oscillations and dynamic displacement with good accuracy. There were slight differences between ultra-rapid, rapid and final products, where some of the tested events indicated that the latter two produced are more accurate and provide better results compared to the ultrarapid product for monitoring short-term dynamic displacements.

Synthesis of Thermosensitive Nanohydrogels by Crosslinker Free Method Based on N-Isopropylacrylamide: Applicable in the Naltrexone Sustained Release

Marziyeh Fathi,Ali Akbar Entezami,Ali Ebrahimi,Kazem Dindar Safa 한국고분자학회 2013 Macromolecular Research Vol.21 No.1

A unique and rapid method was used to synthesize thermosensitive self-crosslinked nano (N-isopropylacrylamide-vinylpyrrolidone-acrylamide) (NIPAAm-VP-AAm) terpolymers. Nanohydrogels were obtained within 30 min during a polymerization reaction with a convenient yield due to the high dilution of aqueous solution at an elevated temperature. Furthermore, hydrogen peroxide (H2O2) was employed for the first time as a safe initiator without any toxic segments for the thermosensitive polymer synthesis. Different nanohydrogels were obtained by modulating the molar ratio of monomers to initiators and their influences on the composition ratios, thermoresponsive behavior, size distribution, phase separation, and nanohydrogel drug release were investigated. As the synthetic route is crosslinker free, the obtained nanohydrogels can be introduced as a non-toxic efficient drug delivery system (DDS). The possibility of free radical formation on the PNIPAAm chains, which leads to the crosslinked structure,has been investigated theoretically by quantum mechanical calculations. The potential energy surface of the reaction was examined by changing the distance between the OH radical and the H atoms. Considering these calculations,the reaction can proceed from all pathways as it is observed experimentally. The average size of nanohydrogels, as revealed by dynamic light scattering (DLS) and transmission electronic microscopy (TEM), is <50 nm. Finally, naltrexone as an opiate antagonist was selected as a model drug for the investigation of nanohydrogel drug delivery capabilities. Nanohydrogels show sustained naltrexone release beyond 3 months without any initial burst release.

Systematic Reliability Study of Top-Gate p- and n-Channel Organic Field-Effect Transistors

Hwang, Do Kyung,Fuentes-Hernandez, Canek,Fenoll, Mathieu,Yun, Minseong,Park, Jihoon,Shim, Jae Won,Knauer, Keith A.,Dindar, Amir,Kim, Hyungchul,Kim, Yongjin,Kim, Jungbae,Cheun, Hyeunseok,Payne, Marcia American Chemical Society 2014 ACS APPLIED MATERIALS & INTERFACES Vol.6 No.5

<P>We report on a systematic investigation on the performance and stability of p-channel and n-channel top-gate OFETs, with a CYTOP/Al<SUB>2</SUB>O<SUB>3</SUB> bilayer gate dielectric, exposed to controlled dry oxygen and humid atmospheres. Despite the severe conditions of environmental exposure, p-channel and n-channel top-gate OFETs show only minor changes of their performance parameters without undergoing irreversible damage. When correlated with the conditions of environmental exposure, these changes provide new insight into the possible physical mechanisms in the presence of oxygen and water. Photoexcited charge collection spectroscopy experiments provided further evidence of oxygen and water effects on OFETs. Top-gate OFETs also display outstanding durability, even when exposed to oxygen plasma and subsequent immersion in water or operated under aqueous media. These remarkable properties arise as a consequence of the use of relatively air stable organic semiconductors and proper engineering of the OFET structure.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2014/aamick.2014.6.issue-5/am405424k/production/images/medium/am-2013-05424k_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am405424k'>ACS Electronic Supporting Info</A></P>

Can tumor recurrence be reduced with plasma-kinetic vaporization of the area around the tumor in nonmuscle invasive bladder cancer?

Yüksel Yılmaz,Mehmet Cemal Kahya,Fatma Hüsniye Dilek,Osman Köse,Serkan Özcan,Ertan Can,Yiğit Akın,Batuhan Ergani,Ahmet Selçuk Dindar 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.4

Purpose: To investigate the effect on recurrence of vaporization of the tumor surroundings and suspicious areas with a plasma-kinetic (PK) system after transurethral resection (TUR) of nonmuscle invasive bladder cancer. Materials and Methods: The study included 121 patients with a primary superficial bladder tumor who were randomized as those who underwent TUR with the PK system (Group 1, n=62) and those who underwent TUR with the monopolar system (Group 2, n=59). The vaporization procedure was performed by suppressing the cutting option of the PK system for a period, which would accumulate energy sufficient to make swelling-waves on the mucosa very close to the area of the loop to be vaporized. Results: A total of 121 patients who met the study criteria were included for evaluation. Recurrence was determined in 21 patients in Group 1 (33.87%) and in 29 patients in Group 2 (49.15%) (p=0.088). Recurrence was close to the old resection site in 6 of 21 patients in Group 1, and in 13 patients in Group 2 (p=0.028); the difference was statistically significant. No statistically significant difference was determined between the two groups with respect to age, gender, number of tumor foci, rate or range of additional treatments applied, cigarette smoking rate, repeat TUR rate and rate of tumor en- countered in repeat TUR, T-stage, and tumor grade. Conclusions: The effect of vaporization on recurrence by the PK system may seem similar to the effect of standard TUR, the recurrence- lowering effect surrounding nonmuscle invasive bladder cancers is better.