Thermodynamic assessment of the Cu−Pt system

A CALPHAD assessment of the Cu−Pt system has been carried out. Two and four sublattice models were applied to describe the Gibbs free energies of ordered phases where the contribution of SRO is taken explicity into account through the reciprocal parameters. The disordered fcc A1 and liquid phases were treated as substitutional solutions. A consistent set of parameters for the phases in the Cu−Pt system as obtained, and those parameters can satisfactorily reproduce the experimental phase equilibria and thermodynamic properties, such as enthalpies, activity of Cu, and long-range order parameters. This paper was presented at the International Symposium on User Aspects of Phase Diagrams. Materials Solutions Conference and Exposition, Columbus, Ohio, 18–20 October, 2004.     

Sustainability assessment of cities: SDGs and GHG emissions

ABSTRACT

The United Nations’ (UN) sustainable development goals (SDGs), the core of the 2030 Agenda for Sustainable Development and the UN Paris Agreement, were adopted in 2015. Involvement of not only national governments but also all other stakeholders including local governments is important to promote sustainable development and to achieve the goals. The question arises, therefore, of what methods should be used to best implement and assess sustainability issues at a local level. In this light, a new version of Comprehensive Assessment System for Built Environment Efficiency (CASBEE), CASBEE for Cities, is introduced for assessing the sustainability of cities and communities around the world based on SDG indicators and greenhouse gas (GHG) emissions. The tool allows users to understand the sustainability of cities and communities based on quality (Q) and environmental load (L) perspectives. The sustainability assessments show that cities in developed countries tend to have good grades for Q, but bad grades for L, while cities in developing countries tend to have the opposite trend. This will assist cities and communities in both developed and developing countries to understand urgent problems and to identify effective solutions for sustainable development.     

Processing‐induced changes in total phenolics and procyanidins in clingstone peaches

Clingstone peaches contain a wide array of complex secondary plant metabolites and polyphenolics, and increasing evidence indicates that many of these components are important in human health. Oligomeric flavan‐3‐ol metabolites (procyanidins) are particularly interesting owing to their potent antioxidant activity and protective cardiovascular effects. To date, little information is available on how postharvest and processing conditions impact levels of phenolics and procyanidins in fruit. This research addresses the impact of lye peeling, freezing, storage temperature (4 and 30 °C) and three different time–temperature sterilisation combinations on levels of total phenolics (TPs) in Ross clingstone peaches. Additionally, we describe the profile of procyanidin oligomers (monomers through heptamers) in clingstone and freestone peaches and demonstrate a dramatic decrease in procyanidins in thermally processed peaches. TP levels ranged between 316 and 397 mg kg^?1 in peeled peaches and between 376 and 609 mg kg^?1 in unpeeled peaches. Cold storage at 4 °C for 14 days or freezing and storing at ?12 °C for 3 months produced no loss in TPs. Peaches stored at 30 °C for 24 h resulted in a 1.7‐fold increase in TPs. Studies of TPs in peaches processed at temperatures of 213 °F for 40 min, 220 °F for 10 min and 230 °F for 2.4 min indicate that processing above 213 °F decreases levels of both TPs (up to 21%) and procyanidins (up to 100%). Processing at 213 °F for 40 min produced no significant loss in TPs. Furthermore, studies reveal that a 30–43% loss in phenolic levels occurs during the first 3 months in storage after canning. It is clear that both storage and thermal processing conditions profoundly impact the levels of polyphenolics in peaches. More interestingly, these studies indicate that peaches are a rich source of procyanidins, having profiles similar to those found in cocoa, apples, wine and tea. © 2002 Society of Chemical Industry     

Mechanical and thermal properties of potassium salts of poly(ethylene‐co‐ethylacrylate): Polyolefin ionomers in the absence of acid groups

The thermal and mechanical properties of ionomers prepared by partial saponification of poly(ethylene‐co‐ethylacrylate) (EEA) with potassium were investigated by using differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). The Vicat softening temperature (VST) and bending modulus were also evaluated. Molecular design of the present EEA‐based ionomers eliminates acid groups, which affect ionic aggregates for conventional ionomers. The DSC results showed that the melting enthalpy and main crystallization temperature decreased as the ion content increased, whereas on the other hand, the crystal melting temperature at about 360 K did not depend on the ion content, and a secondary exothermal peak was observed in the cooling process. The variance of the VST increased as the crystallinity decreased. The temperature‐dependent curves of DMA data of the EEA‐based potassium ionomers with a higher ion content showed elastic plateau even at temperatures above their crystal melting points. Our results indicate the existence of strong cross‐linking mediated by ion aggregates. The quadratic increase of stiffness as a function of ion content, increasing VST with decreasing crystallinity, and elastic plateau of temperature‐dependent moduli above crystal melting temperature are significant characteristics of the EEA‐based potassium ionomers, which contain ionic aggregations without acid group presence. POLYM. ENG. SCI., 55:1843–1848, 2015. © 2014 Society of Plastics Engineers     

Protein-Protein Recognition Involved in the Intermodular Transacylation Reaction in Modular Polyketide Synthase in the Biosynthesis of Vicenistatin

The ketosynthase (KS) domain is a core domain found in modular polyketide synthases (PKSs). To maintain the polyketide biosynthetic fidelity, the KS domain must only accept an acyl group from the acyl carrier protein (ACP) domain of the immediate upstream module even when they are separated into different polypeptides. Although it was reported that both the docking domain-based interactions and KS-ACP compatibility are important for the interpolypeptide transacylation reaction in 6-deoxyerythronolide B synthase, it is not clear whether these findings are broadly applied to other modular PKSs. Herein, we describe the importance of protein-protein recognition in the intermodular transacylation between VinP1 module 3 and VinP2 module 4 in vicenistatin biosynthesis. We compared the transacylation activity and crosslinking efficiency of VinP2 KS₄ against the cognate VinP1 ACP₃ with the noncognate one. As a result, it appeared that VinP2 KS₄ distinguishes the cognate ACP₃ from other ACPs.     

Quantitative Analysis of The High-Yield Hydrolysis of Kelp by Laminarinase and Alginate Lyase

Kelp is an abundant, farmable biomass-containing laminarin and alginate as major polysaccharides, providing an excellent model substrate to study their deconstruction by simple enzyme mixtures. Our previous study showed strong reactivity of the glycoside hydrolase family 55 during hydrolysis of purified laminarin, raising the question of its reactivity with intact kelp. In this study, we determined that a combination of a single glycoside hydrolase family 55 β-1,3-exoglucanase with a broad-specificity alginate lyase from the polysaccharide lyase family 18 gives efficient hydrolysis of untreated kelp to a mixture of simple sugars, that is, glucose, gentiobiose, mannitol-end glucose, and mannuronic and guluronic acids and their soluble oligomers. Quantitative assignments from nanostructure initiator mass spectrometry (NIMS) and 2D HSQC NMR spectroscopy and analysis of the reaction time-course are provided. The data suggest that binary combinations of enzymes targeted to the unique polysaccharide composition of marine biomass are sufficient to deconstruct kelp into soluble sugars for microbial fermentation.