Investigation on the levitation force behaviour of malic acid added bulk MgB2 superconductors

The effects of malic acid addition (from 0 to 15 wt% of the total MgB 2) on the levitation force properties of bulk MgB2 have been investigated. All samples were prepared from magnesium powder, amorphous boron powder, malic acid (C4H6O5) and toluene (C7H8) by using two-step solid state reaction method. Vertical and lateral levitation force measurements that are under both zero-field-cooled (ZFC) and field-cooled (FC) regimes were carried out at different temperatures of 24, 28 and 32 K for samples with various adding level. It was found that the reasonable malic acid adding has a positive impact on the levitation properties. At 24 K and 28 K, the 4 wt% and 6 wt% malic acid added samples exhibits a higher levitation force than pure sample. In the case of the optimally additive 4 wt% sample, the maximum levitation force corresponds to 18.60 N, whereas the pure sample shows 16.95 N at 24 K for ZFC regime. In this study the enhancing effect of malic acid adding on the levitation force properties of MgB2 has been first time investigated and reported. © 2014 Elsevier B.V. All rights reserved.113T008 110T622The authors are grateful to Prof. Dr. Neriman Demirbaş for great interest and to Elvan Coşkun for the levitation force measurements. This work was supported by Turkish Science and Technology Council-TUBITAK under the Project No. 113T008 . Magnetic levitation force measurements at low temperatures were performed at solid state research laboratory in Recep Tayyip Erdogan University using the system designed by the project supported by the Scientific and Technological Research Council of Turkey (TUBITAK) , with Project No. 110T622

Investigation on the levitation force behaviour of malic acid added bulk MgB2 superconductors

The effects of malic acid addition (from 0 to 15 wt% of the total MgB 2) on the levitation force properties of bulk MgB2 have been investigated. All samples were prepared from magnesium powder, amorphous boron powder, malic acid (C4H6O5) and toluene (C7H8) by using two-step solid state reaction method. Vertical and lateral levitation force measurements that are under both zero-field-cooled (ZFC) and field-cooled (FC) regimes were carried out at different temperatures of 24, 28 and 32 K for samples with various adding level. It was found that the reasonable malic acid adding has a positive impact on the levitation properties. At 24 K and 28 K, the 4 wt% and 6 wt% malic acid added samples exhibits a higher levitation force than pure sample. In the case of the optimally additive 4 wt% sample, the maximum levitation force corresponds to 18.60 N, whereas the pure sample shows 16.95 N at 24 K for ZFC regime. In this study the enhancing effect of malic acid adding on the levitation force properties of MgB2 has been first time investigated and reported. © 2014 Elsevier B.V. All rights reserved.113T008 110T622The authors are grateful to Prof. Dr. Neriman Demirbaş for great interest and to Elvan Coşkun for the levitation force measurements. This work was supported by Turkish Science and Technology Council-TUBITAK under the Project No. 113T008 . Magnetic levitation force measurements at low temperatures were performed at solid state research laboratory in Recep Tayyip Erdogan University using the system designed by the project supported by the Scientific and Technological Research Council of Turkey (TUBITAK) , with Project No. 110T622

Investigation on the levitation force behaviour of malic acid added bulk MgB2 superconductors

Ozturk, Kemal/0000-0002-8847-1880; Celik, Sukru/0000-0002-6918-7569WOS: 000336426300012The effects of malic acid addition (from 0 to 15 wt% of the total MgB2) on the levitation force properties of bulk MgB2 have been investigated. All samples were prepared from magnesium powder, amorphous boron powder, malic acid (C4H6O5) and toluene (C7H8) by using two-step solid state reaction method. Vertical and lateral levitation force measurements that are under both zero-field-cooled (ZFC) and field-cooled (FC) regimes were carried out at different temperatures of 24, 28 and 32 K for samples with various adding level. It was found that the reasonable malic acid adding has a positive impact on the levitation properties. At 24 K and 28 K, the 4 wt% and 6 wt% malic acid added samples exhibits a higher levitation force than pure sample. in the case of the optimally additive 4 wt% sample, the maximum levitation force corresponds to 18.60 N, whereas the pure sample shows 16.95 N at 24 K for ZFC regime. in this study the enhancing effect of malic acid adding on the levitation force properties of MgB2 has been first time investigated and reported. (C) 2014 Elsevier B.V. All rights reserved.Turkish Science and Technology Council-TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [113T008]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [110T622]The authors are grateful to Prof. Dr. Neriman Demirbas for great interest and to Elvan Coskun for the levitation force measurements. This work was supported by Turkish Science and Technology Council-TUBITAK under the Project No. 113T008. Magnetic levitation force measurements at low temperatures were performed at solid state research laboratory in Recep Tayyip Erdogan University using the system designed by the project supported by the Scientific and Technological Research Council of Turkey (TUBITAK), with Project No. 110T622

Effect of Adding on the Critical Current Density and Lateral Levitation Force of Bulk

WOS: 000360230200004We fabricated malic acid -added bulks by wet mixing and "Two-step solid state reaction method". The effects of adding malic acid on , behaviour and lateral levitation force features of bulk have been investigated. A systematic decrease in the critical temperature with increasing adding level confirms the substitution of C at the B site of . While the 4 wt% sample showed the best of at 4 T and 5 K, 15 wt% sample showed uncompetitive lower critical current density , which ascribes the poor connectivity due to the excessive unsubstituted C distribution at grain boundaries and the presence of high MgO amount. At 24 and 28 K, the 4 and 6 wt% malic-acid-added samples exhibit a higher lateral force than pure sample. Based on the observed values of M-H, (H) and lateral levitation force , it can be concluded that the 4 wt% malic-acid-added sample is the best of the studied samples.Turkish Science and Technology Council-TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [113T008]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [110T622]This work was supported by Turkish Science and Technology Council-TUBITAK under the Project Number 113T008. Magnetic levitation force measurements at low temperatures were performed at solid state research laboratory in Recep Tayyip Erdogan University using the system designed by the project supported by the Scientific and Technological Research Council of Turkey (TUBITAK), with Project No. 110T622

Modification of chitosan-bead support materials with l-lysine and l-asparagine for alpha-amylase immobilization

WOS: 000425280600011PubMed ID: 29222588Maltose syrups have got wide-range utilizations in a variety of applications from bakery to drug-development. alpha-Amylases are among the most widely utilized industrial enzymes due to their high specificity in production of maltose syrup from starch. However, enzymes are not stable in ex vivo conditions towards alteration in pH, temperature, and such other parameters as high salt concentrations and impurities, where immobilization is required to advance the stability of the enzyme with which approach the requirement of isolation of the enzyme from media is eliminated as well. In this study, Termamyl(A (R)) alpha-amylase was immobilized on the none-modified chitosan beads (NMCB), l-lysine-modified chitosan beads (LMCB), and l-asparagine-modified chitosan beads (AMCB) to assess effects of the support material on optimum conditions and kinetic parameters of the alpha-amylase activity in production of maltose from starch. Immobilization on NMCB, LMCB, and AMCB puts a strong influence on optimum pH, optimum temperature, stability, and kinetic parameters of alpha-amylase. Modification of chitosan beads with l-lysine and l-asparagine dramatically altered the overall immobilization yield, and enzyme's response to pH and temperature variations and the kinetic parameters. AMCB provided the best immobilization yield (49%), while LMCB only improved the yield by 2% from 22 to 24%.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [106M241]This study was partly supported by The Scientific and Technological Research Council of Turkey (TUBITAK) with 106M241 project number

Caffeic acid phenethyl ester protects against oxidative stress and dampens inflammation via heme oxygenase 1

Periodontal disease is associated with chronic oxidative stress and inflammation. Caffeic acid phenethyl ester (CAPE), which is a potent inducer of heme oxygenase 1 (HO1), is a central active component of propolis, and the application of propolis improves periodontal status in diabetic patients. Here, primary murine macrophages were exposed to CAPE. Target gene expression was assessed by whole-genome microarray, RT-PCR and Western blotting. The antioxidative and anti-inflammatory activities of CAPE were examined by exposure of the cells to hydrogen peroxide, saliva and periodontal pathogens. The involvement of HO1 was investigated with the HO1 inhibitor tin protoporphyrin (SnPP) and knockout mice for Nrf2, which is a transcription factor for detoxifying enzymes. CAPE increased HO1 and other heat shock proteins in murine macrophages. A p38 MAPK inhibitor and Nrf2 knockout attenuated CAPE-induced HO1 expression in macrophages. CAPE exerted strong antioxidative activity. Additionally, CAPE reduced the inflammatory response to saliva and periodontal pathogens. Blocking HO1 decreased the antioxidative activity and attenuated the anti-inflammatory activity of CAPE. In conclusion, CAPE exerted its antioxidative effects through the Nrf2-mediated HO1 pathway and its anti-inflammatory effects through NF-κB inhibition. However, preclinical models evaluating the use of CAPE in periodontal inflammation are necessary in future studies