Improving the Properties of Industrial Polyurethane with Nanoclay, Hectorite

M.O. Seydibeyo?lu,F.S. Guner,I. Ece,S. Iscli,N. Gungor 한국고분자학회 2006 한국고분자학회 학술대회 연구논문 초록집 Vol.2006 No.10

Astrochemical Properties of Planck Cold Clumps

Tatematsu, Ken’ichi,Liu, Tie,Ohashi, Satoshi,Sanhueza, Patricio,Nguyê,̃,n Lu’o’, Quang,Hirota, Tomoya,Liu, Sheng-Yuan,Hirano, Naomi,Choi, Minho,Kang, Miju,A.Thompson, Mark,Fuller, Gary,Wu, Y Published by the University of Chicago Press for t 2017 The Astrophysical journal Supplement series Vol.228 No.2

<P>We observed 13 Planck cold clumps with the James Clerk Maxwell Telescope/SCUBA-2 and with the Nobeyama 45 m radio telescope. The N2H+ distribution obtained with the Nobeyama telescope is quite similar to SCUBA-2 dust distribution. The 82 GHz HC3N, 82 GHz CCS, and 94 GHz CCS emission are often distributed differently with respect to the N2H+ emission. The CCS emission, which is known to be abundant in starless molecular cloud cores, is often very clumpy in the observed targets. We made deep single-pointing observations in DNC, (HNC)-C-13, N2D+, and cyclic-C3H2 toward nine clumps. The detection rate of N2D+ is 50%. Furthermore, we observed the NH3 emission toward 15 Planck cold clumps to estimate the kinetic temperature, and confirmed that most targets are cold (less than or similar to 20 K). In two of the starless clumps we observed, the CCS emission is distributed as it surrounds the N2H+ core (chemically evolved gas), which resembles the case of L1544, a prestellar core showing collapse. In addition, we detected both DNC and N2D+. These two clumps are most likely on the verge of star formation. We introduce the chemical evolution factor (CEF) for starless cores to describe the chemical evolutionary stage, and analyze the observed Planck cold clumps.</P>

Multilevel Noncontiguous Spinal Fractures: Surgical Approach towards Clinical Characteristics

Mehmet Seçer,Fatih Alagöz,Ozhan Uçkun,Oğuz Durmuş Karakoyun,Murat Ömer Ulutaş,Ömer Polat,Ergün Dağlıoğlu,Ali Dalgıç,Deniz Belen 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.6

Study Design: The study retrospectively investigated 15 cases with multilevel noncontiguous spinal fractures (MNSF). Purpose: To clarify the evaluation of true diagnosis and to plane the surgical treatment. Overview of Literature: MNSF are defined as fractures of the vertebral column at more than one level. High-energy injuries caused MNSF, with an incidence ranging from 1.6% to 16.7%. MNSF may be misdiagnosed due to lack of detailed neurological and radiological examinations. Methods: Patients with metabolic, rheumatologic diseases and neoplasms were excluded. Despite the presence of a spinal fracture associated clearly with the clinical picture, all patients were scanned within spinal column by direct X-rays, computed tomography and magnetic resonance imaging. When there were ≥5 intact vertebrae between two fractured vertebral segments, each fracture region was managed with a separated stabilization. In cases with ≤4 intact segments between two fractured levels, both fractures were fixed with the same rod and screw system. Results: There were 32 vertebra fractures in 15 patients. Eleven (73.3%) patients were male and age ranged from 20 to 64 years (35.9±13.7 years). Eleven cases were the American Spinal Injury Association (ASIA) E, 3 were ASIA A, and one was ASIA D. Ten of the 15 (66.7%) patients returned to previous social status without additional deficit or morbidity. The remaining 5 (33.3%) patients had mild or moderate improvement after surgery. Conclusions: The spinal column should always be scanned to rule out a secondary or tertiary vertebra fracture in vertebral fractures associated with high-energy trauma. In MNSF, each fracture should be separately evaluated for decision of surgery and planned approach needs particular care. In MNSF with ≤4 intact vertebra in between, stabilization of one segment should prompt the involvement of the secondary fracture into the system.

Importance of Mechatronics in Maritime Education

Yalçın DURMUŞOĞLU,Cengiz DENİZ,Y. Volkan Aydoğdu,A. Atıl TALAY 한국항해항만학회 2012 한국항해항만학회 학술대회논문집 Vol.2012 No.공동학술

The Determination of Fracture Characterization of Knitted Fabric Reinforced Composites Using Arcan Test

H. Ersen Balcıoğlu,Derviş Yalçın 한국섬유공학회 2020 Fibers and polymers Vol.21 No.4

Type, structure and orientation angle of the reinforcing material used in laminated composite structures directlyaffect the mechanical behavior of the composite material. Knitted fabrics are becoming increasingly widespread asreinforcing materials in laminated composites due to their superior mechanical and physical properties. In this study,mechanical properties and fracture toughness of knitted fabric reinforced laminated composites were investigated. 1×1 ribknitted fabric reinforced glass/epoxy and carbon/epoxy laminated composites were produced by hand lay-up method. Mechanical behaviors of the produced composites were determined under tensile, compressive and shear loads. The fracturetoughness of the knitted fabric reinforced composites was determined under Mode I (0 o), Mode II (90 o) and Mode I/II (30 o,45 o, and 60 o) loading conditions by using Arcan test apparatus. In addition, the fracture toughness of glass/epoxy andcarbon/epoxy laminated composites were numerically determined using the J integral method in the ANSYS finite elementprogram. Test results have shown that knitted fabrics can be used as an alternative reinforcing material in the production oflaminated composites.

Effects of Systemic and Local Interferon Beta-1a on Epidural Fibrosis

Mevlüt Özgür Taşkapılıoğlu,Semra Işık,Şeref Doğan,Gonca Özgün,Gökhan Ocakoğlu,Nesrin Uğraş 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.3

Study Design: Level 1 randomized controlled study. Purpose: To investigate the effects of systemic and local interferon-beta-1a (IFN-β-1a) on prevention of epidural fibrosis using histopathological parameters. Overview of Literature: Epidural fibrosis involves fibroblastic invasion of nerve roots into the epidural space. Formation of dense fibrous tissue causes lumbar and radicular pain. Many surgical techniques and several materials have been proposed in the literature, but no study has assessed the effect of IFN-β-1a on prevention of epidural fibrosis. Methods: Forty-eight adult female Sprague-Dawley rats were divided into six groups of eight: sham group, control group, systemic 44 μg IFN-β-1a group and 22 μg IFN-β-1a group (after laminectomy and discectomy, 0.28 mL and 0.14 mL IFN-β-1a applied subcutaneously three times for a week, respectively), local 44 μg IFN-β-1a group (laminectomy and discectomy, followed by 0.28 mL IFN-β-1a on the surgical area), and local 22 μg IFN-β-1a group (laminectomy and discectomy, followed by 0.14 mL IFN-β-1a on the surgical area). All rats were sacrificed after 4 weeks and groups were evaluated histopathologically. Results: Compared with sham and control groups, significantly less epidural fibrosis, dural adhesion, and fibroblast cell density were observed in the local and systemic 44 μg IFN-β-1a groups. No other differences were evident between the local and systemic groups. Conclusions: IFN-β-1a is effective in preventing epidural fibrosis with systemic and local application.

Protective Effect of Ginkgo biloba L. Leaf Extract Against Glyphosate Toxicity in Swiss Albino Mice

Kültiğin Çavuşoğlu,Kürşad Yapar,Ertan Oruç,Emine Yalçın 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.10

The aim of the present study was to investigate the protective role of Ginkgo biloba L. leaf extract against the active agent of Roundup^ⓡ herbicide (Monsanto, Creve Coeur, MO, USA). The Swiss Albino mice were randomly divided into six groups, with each group consisting of six animals: Group I (control) received an intraperitoneal injection of dimethyl sulfoxide (0.2 mL, once only), Group II received glyphosate at a dose of 50 mg/kg of body weight, Group III received G. biloba at a dose of 50 mg/kg of body weight, Group IV received G. biloba at a dose of 150 mg/kg of body weight, Group V received G. biloba (50 mg/kg of body weight) and glyphosate (50 mg/kg of body weight), and Group VI received G. biloba (150 mg/kg of body weight) and glyphosate (50 mg/kg of body weight). The single dose of glyphosate was given intraperitoneally. Animals from all the groups were sacrificed at the end of 72 hours, and their blood, bone marrow, and liver and kidney tissues were analyzed for aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), creatinine, malondialdehyde (MDA), and glutathione (GSH) levels and the presence of micronucleus (MN), chromosomal aberrations (CAs), and pathological damages. The results indicated that serum AST, ALT, BUN, and creatinine levels significantly increased in mice treated with glyphosate alone compared with the other groups (P<.05). Besides, glyphosate-induced oxidative damage caused a significant decrease in GSH levels and a significant increase in MDA levels of the liver and kidney tissues. Moreover, glyphosate alone–treated mice presented higher frequencies of CAs, MNs, and abnormal metaphases compared with the controls (P<.05). These mice also displayed a lower mean mitotic index than the controls (P<.05). Treatment with G. biloba produced amelioration in indices of hepatotoxicity, nephrotoxicity, lipid peroxidation, and genotoxicity relative to Group II. Each dose of G. biloba provided significant protection against glyphosate-induced toxicity, and the strongest effect was observed at a dose of 150 mg/kg of body weight. Thus, in vivo results showed that G. biloba extract is a potent protector against glyphosate-induced toxicity, and its protective role is dose-dependent.

Preconcentration and Determination of Fe(III) from Water and Food Samples by Newly Synthesized Chelating Reagent Impregnated Amberlite XAD-16 Resin

Şerife Tokalıoğlu,Hasan Ergün,Alaaddin Çukurovalı 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.7

A simple and reliable method has been developed to selectively separate and concentrate trace amounts of Fe(III)ions from water and food samples by using flame atomic absorption spectrometry. A new reagent, 5-hydroxy-4-ethyl-5,6-di-pyridin-2-yl-4,5-dihydro-2H-[1,2,4] triazine-3-thione, was synthesized and characterized by using FT-IR spectroscopy and elemental analysis. Effects of pH, concentration and volume of elution solution, sample flow rate,sample volume and interfering ions on the recovery of Fe(III) were investigated. The optimum pH was found to be 5. Eluent for quantitative elution was 10 mL of 2 M HCl. The preconcentration factor of the method, detection limit (3s/b, μg L‒1) and relative standard deviation values were found to be 25, 4.59 and 1%, respectively. In order to verify the accuracy of the method, two certified reference materials (TMDA 54.4 lake water and SRM 1568a rice flour) were analyzed. The results obtained were in good agreement with the certified values. The method was successfully applied to the determination of Fe(III) ions in water and food samples.

The Protective Effect of Royal Jelly on Chronic Lambda-Cyhalothrin Toxicity: Serum Biochemical Parameters, Lipid Peroxidation, and Genotoxic and Histopathological Alterations in Swiss Albino Mice

Kültiğin Çavuşoğlu,Kürşad Yapar,Ertan Oruç,Emine Yalçın 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.10

The present study was undertaken to investigate the protective effect of royal jelly (RJ) against toxicity induced by a synthetic pyrethroid insecticide, lambda-cyhalothrin (LCT), in Swiss albino mice. Animals were randomly divided into six groups of six animals each. The control group received distilled water alone, whereas mice in the treatment groups received RJ alone (100 or 250 mg/kg of body weight), LCT alone (668 ppm), or RJ+LCT for 21 days. All mice (100%) survived until the end of experiment and were sacrificed at the end of 24 hours. Blood, bone marrow, and liver and kidney tissues were analyzed for aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), creatinine, malondialdehyde (MDA), and reduced glutathione (GSH) levels and micronucleus (MN) frequency, chromosomal aberrations (CAs), and pathological damages. Serum AST, ALT, BUN, and creatinine levels were elevated in mice treated with LCT alone compared with the other tested groups (P<.05). LCT-induced oxidative damage caused a significant decrease in GSH levels and a significant rise in MDA levels of liver and kidney tissues. LCT alone–treated mice presented higher frequencies (P<.05) of MNs, CAs, and abnormal metaphases compared with the controls; moreover, the mitotic index was lower than in controls (P<.05). Oral treatment with RJ significantly ameliorated the indices of hepatotoxicity, nephrotoxicity, lipid peroxidation, and genotoxicity induced by LCT. Both doses of RJ tested provided significant protection against LCT-induced toxicity, and its strongest effect was observed at the dose level of 250 mg/kg of body weight. In vivo results suggest that RJ is a potent antioxidant against LCT-induced toxicity, and its protective effect is dose dependent.

The Synthesis of New Type II Polymeric Photoinitiator (thioxantone) via Atom Transfer Radical Polymerization and Their Curing and Migration Studies

Emine Arman Kandirmaz,Efe N. Gençoğlu,Nilhan Kayaman Apohan 한국고분자학회 2019 Macromolecular Research Vol.27 No.8

Polymeric photoinitiators are widely used in ultraviolet (UV)-curable printing inks because of their low migration behavior. In this study, a new phenylphosphine oxide-polystyrene-thioxanthone (PPO-PSt-TX) polymeric photoinitiator was synthesized. Bis[(4-hydroxy)phenyl]phenyl phosphine oxide (BHPPO) that was synthesized by Grignard technique, was functionalized with 2-bromopropionyl bromide (atom transfer radical polymerization (ATRP) initiator) and then used in styrene polymerization. The bromine end-capped polystyrene was then reacted with 2-thioxanthone-thioacetic acid and final polymeric photoinitiator PPO-PSt-TX was obtained. Proton nuclear magnetic resonance (1H NMR), attenuated total reflectance- Fourier transform infrared spectroscopy (ATR-FTIR), gel permeation chromatography (GPC) and ultraviolet-visible spectroscopy (UV-Vis) confirmed the obtained structure. The curing characteristic of PPO-PSt-TX was compared with a standard flexographic printing varnish formulation containing thioxanthone (TX). The photopolymerization kinetics were determined by photo differential scanning calorimetry (Photo-DSC). The conversion of methylmethacrylate polymerization by using macrophotoinitiator is 78%. The migration behavior of PPO-PSt-TX was identified with liquid chromatography-mass spectrometry (LC-MS). It was shown that PPOPSt- TX macro photoinitiator is suitable for flexographic varnish and the migration level of photoinitiator is reduced by using polymeric photoinitiator.