Volume 87, Issue 11-12

A short overview of recent advances in studies of the interactions between natural polymers and application of polymers from natural sources as components of the blends for biomedical and cosmetic applications is presented. This work is focused on the blends of collagen, chitosan, silk fibroin and keratin. These bioinspired and biobased materials can be good alternative for materials based on synthetic polymers. The case study of the blends made of collagen and keratin hydrolysate is presented.

A versatile strategy to integrate multiple functions in a polymer based material is the formation of polymer networks with defined nanostructures. Here, we present synthesis and comprehensive characterization of covalently surface functionalized magnetic nanoparticles (MNPs) comprising a bi-layer oligomeric shell, using Sn(Oct) 2 as catalyst for a two-step functionalization. These hydroxy-terminated precursors for degradable magneto- and thermo-sensitive polymer networks were prepared via two subsequent surface-initiated ring-opening polymerizations (ROPs) with ω -pentadecalactone and ε -caprolactone. A two-step mass loss obtained in thermogravimetric analysis and two distinct melting transitions around 50 and 85°C observed in differential scanning calorimetry experiments, which are attributed to the melting of OPDL and OCL crystallites, confirmed a successful preparation of the modified MNPs. The oligomeric coating of the nanoparticles could be visualized by transmission electron microscopy. The investigation of degrafted oligomeric coatings by gel permeation chromatography and 1 H-NMR spectroscopy showed an increase in number average molecular weight as well as the presence of signals related to both of oligo( ω -pentadecalactone) (OPDL) and oligo( ε -caprolactone) (OCL) after the second ROP. A more detailed analysis of the NMR results revealed that only a few ω -pentadecalactone repeating units are present in the degrafted oligomeric bi-layers, whereby a considerable degree of transesterification could be observed when OPDL was polymerized in the 2 nd ROP step. These findings are supported by a low degree of crystallinity for OPDL in the degrafted oligomeric bi-layers obtained in wide angle X-ray scattering experiments. Based on these findings it can be concluded that Sn(Oct) 2 was suitable as catalyst for the preparation of nanosized bi-layered coated MNP precursors by a two-step ROP.

The term oceanic salts concerns the salts, which can be formed from solutions containing the major ions of seawater, that is the hexary system Na + , K + , Mg ++ , Ca ++ , Cl – , SO 4 – –H 2 O. Besides in geochemistry of evaporites and the potash extraction the solubility equilibria and properties of aqueous solutions containing these ions are of importance in many fields of science and technology in a wide range of temperature and composition. After a short introduction into the types of subsystems and the main features of their solubility diagrams the known salt phases, their properties and stability are listed and discussed with a focus on recent work and discoveries. The status of solubility data evaluation of the multi-component system is discussed from the view point of the data itself and the possibilities and limitations of applying thermodynamic modelling. This is demonstrated with the data compilation of Usdowski and Dietzel, the Pitzer models of Harvie, Möller and Weare as well as the model developed in the THEREDA project. Future work should be directed to improve accuracy of solubility data in multi-component solutions combined with modelling and to consider kinetics and mechanistic aspects in crystallization of phases like anhydrite or polyhalite.

This paper details an approach to re-purposing scientific data as presented on a web page for the sole purpose of making the data more available for searching and integration into other websites. Data ‘scraping’ is used to extract metadata from a set of pages on the National Institute of Standards and Technology (NIST) website, clean, organize and store the metadata in a MySQL database. The metadata is then used to create a new website at the authors institution using the CakePHP framework to create a representational state transfer (REST) style application program interface (API). The processes used for website analysis, schema development, database construction, metadata scraping, REST API development, and remote data integration are discussed. Lessons learned and tips and tricks on how to get the most out of the process are also included.

Recommendations are made for standard potentials involving select inorganic radicals in aqueous solution at 25 °C. These recommendations are based on a critical and thorough literature review and also by performing derivations from various literature reports. The recommended data are summarized in tables of standard potentials, Gibbs energies of formation, radical p K a ’s, and hemicolligation equilibrium constants. In all cases, current best estimates of the uncertainties are provided. An extensive set of Data Sheets is appended that provide original literature references, summarize the experimental results, and describe the decisions and procedures leading to each of the recommendations.

Ports are closed or semi-closed coastal systems with limited water circulation, poor flushing and weak tidal exchange. They are characterized as pollution hotspots or areas of stagnation with a variety of maritime pollutants. Nowadays, shipping and port managers aim to address environmental risk in their operations, striving to achieve suitable environmental management systems and environmental policies. In that way, environmental impacts are thoroughly considered, actions to minimize and prevent these effects are identified while human activities for prevention, reduction and mitigation of harmful consequences are managed. The current project provides details of quality and performance indicators, based on physical and biogeochemical environmental parameters required to monitor and audit the effectiveness of environmental management system and environmental policy applied in ports. These indicators will be used as powerful tools strengthening sound decisions when developing, shaping and evaluating national and local environmental management systems and policies. The selected indicators are described and their monitoring processes are presented and discussed. Examples of selected best environmental practice from various port authorities are included.