Investigation on the effect of phase segregation on the mechanical properties of polymer modified bitumen using analytical and morphological tools

The mechanical strength of polymer modified bituminous mix which is evaluated in terms of stiffness reflects the deformation behaviour of bituminous mixture. The stiffness of the binder strongly depends on its chemical composition besides aggregate structure of the bituminous mixture. Compatibility of polymer with the base bitumen is considered as major strength enhancing factor in the case of polymer modified bituminous mix. To relate the factors affecting the mechanical strength of the binder a new approach in this research study was adopted in order to relate the compatibility of 80/100 pen bitumen with polymer Polypropylene (PP) using analytical and morphological tools. Morphological tools like Atomic Force Microscopy (AFM) and Transmission Electron Microscope (TEM) were used to study the changes due to the difference in compatibility of polymer with bitumen. It was observed that the presence of phase segregated layer as observed by AFM surface morphology was considered as the main strength enhancing factor of the bituminous mix. While the presence of lamella as observed in TEM scanned images of PP PMB revealed that addition of polymer forms localized network in the phase segregated layer which induces the stiffening effect in PMB. From the chromatographic method (SARA) analytical analysis Saturate, Aromatics, Resin and Asphaltene fractionate were determined in the blend. It was observed that chemical composition of the blend also has a profound effect on the rheological properties and on the morphology of polymer modified bituminous (PMB) blend. It was concluded that PP PMB gets benefited by phase segregated layer in the blend when the polymer concentration was kept below 3% as it sufficiently enhances the mechanical strength of the PMB binder as observed by dynamic creep results

Structural and kinetic studies in propene oxidation over Sb oxide dispersed on TiO2

Antimony oxide dispersed on TiO2 was characterized using FTIR, Raman, and Auger spectroscopies as well as XRD. They indicate that the electronic environment about Sb is perturbed at low concentration suggesting that the structure of Sb oxide on TiO2 is somewhat distorted as compared to Sb6O13. The oxidation of labeled propene such as CH2=CH---CD3, 13CH2=CH---CH3, and cis-CHD=CD---CH3 was examined on Sb6O13 and Sb---Ti oxide catalysts. The results indicate that the first hydrogen abstraction is rate determining and that there is little or no isotope effect in the second hydrogen abstraction over Sb and Sb---Ti oxide catalysts. The oxidation kinetics was discussed on the basis of a modified redox mechanism. The reduction step was promoted by a factor of ca. 50 over Sb oxide dispersed on TiO2 as compared to that on unsupported Sb6O13. Rate promotion was mainly attributed to the increase in the amount of active sites for the reduction step.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29491/1/0000577.pd

Interleukin-4 downregulates the cyclic tensile stress-induced matrix metalloproteinases-13 and cathepsin b expression by rat normal chondrocytes

Mechanical stress plays a key role in the pathogenesis of cartilage destruction seen in osteoarthritis (OA). We investigated the effect of cyclic tensile stress (CTS) on the anabolic and catabolic gene expression of rat cultured normal chondrocytes using the Flexercell strain unit. The effects of interleukin (IL)-4, a chondroprotective cytokine, on the changes in gene expression induced by CTS were also investigated. CTS (7% elongation at 0.5 Hz) for 24 h did not affect the expression of aggrecan and type II collagen, whereas CTS significantly upregulated matrix metalloproteinase (MMP)-13 and cathepsin B mRNA expression by chondrocytes. IL-1beta expression was also signifi cantly upregulated by CTS up to 12 h. The upregulation of MMP-13 was observed at 3 h, which was earlier than that of IL-1beta. Furthermore, pre-treatment with IL-4 (10 ng/ml) suppressed both MMP-13 and cathepsin B induction by mechanical stress, as well as CTS-induced IL-1beta expression. Our results suggest that IL-4 might have a therapeutic value in the treatment of OA by downregulation of mechanical stress-induced MMP-13 and cathepsin B expression by chondrocytes.</p

High-absorption curcumin reduces BNP in hypertensive heart disease

Aims Hypertension is a strong risk factor for heart failure with preserved ejection fraction. Curcumin has p300-specific histone acetyltransferase inhibitory activity, suppresses cardiomyocyte hypertrophy and fibrosis, and significantly reduces myocardial brain natriuretic peptide (BNP) expression without altering blood pressure in a rat model of hypertensive heart disease. This double-blind, placebo-controlled, randomized study, for the first time, aimed to examine the efficacy of a high-absorption curcumin for the prevention of hypertensive heart disease in humans. Methods and results Patients exhibiting initial signs of hypertensive heart disease with left ventricular ejection fraction ≥60% and stable blood pressure <140/90 mmHg orally took a double-blinded capsule (either a 90 mg curcumin capsule or placebo) twice daily for 24 weeks. The primary endpoint was per cent changes in left ventricular diastolic function (E/E′) from baseline to 6 months after administration. The secondary endpoint was the per cent change in plasma BNP levels. The E/E′ ratio per cent change from baseline to 6 months after administration was similar between the placebo (n = 69) and the curcumin (n = 73) groups. The per cent change in plasma BNP levels was significantly lower in the curcumin group than in the placebo group. In patients <65 years, BNP per cent changes were significantly lower in the curcumin group than in the placebo group, but similar between groups in ≥65 years (<65 vs. ≥65 years: P for interaction = 0.011). Conclusions A high-absorption curcumin agent did not affect the E/E′ ratio, rather it significantly inhibited the increase in plasma BNP levels in patients with initial signs of hypertensive heart disease

広島における原爆・核・被ばく関連の史・資料の集積と研究の現況

研究成果の概要～核・被ばく学の方向性と課題～…小池　聖一 1 第一部　研究会速記録　 広島県立文書館所蔵原爆関係資料について…安藤　福平 5　 広島平和記念資料館の所蔵資料について…落葉　裕信 44　 原爆被災資料の収集・整理・保存～広島大学勤務期…宇吹　暁 94　 広島市公文書館が所蔵する原爆関係資料について…渡辺　琴代 139　 広島大学文書館所蔵平和関係資料について…小池　聖一 174　 第二部　個別研究　 「原子のペスト」と低線量被爆…布川　弘 201　 2010年―2013年の核をめぐる動向と課題…水本　和実 209　 第三部　調査報告　 原爆報道…石田　雅春 261　 被爆者対策の国際比較…川野　徳幸 266　 平和教育…小宮山道夫 271　 核の戦争責任論…永井　均 277　広島における核・被ばく学研究基盤の形成に関する研究（課題番号：23300096） 平成23年度科学研究費補助金基盤研究（B）研究成果報告

Preparation of Graphene Oxide from Lignin by Gel Combustion Method and Its Performance as Supercapacitor

Carbon materials derived from biomass are drawing increasing attention due to its advantages in economical as well as ecological production. Among the biomass resources to be utilized for that purpose, lignin possesses unique characteristics: it is available in bulk quantity as a low-value by-product from the pulp and paper industries and its chemical structure based on complex aromatic networks provides excellent precursor for grahitic carbon materials such as graphene. The existing techniques to convert lignin to carbon materials require long processing time, complex steps and higher temperatures, thus increasing the production cost and hindering its commercialization. Here an alternate low-cost, one-pot synthesis method utilizing organic solvent gel combustion technique is developed to yield crystalline graphene oxide as an end product. Capacitor performance of the developed graphene oxide was investigated in terms of the parameters involved in the synthesis procedure