Surface preparation of historic wrought iron: evidencing the requirement for standardisation

The conservation of heritage wrought iron mostly relies on corrosion prevention by preparation of surfaces and application of protective coatings. In contrast to industrial and engineering treatment of modern steel, conservation practice is not regulated by accepted national and international standards or underpinned by empirical evidence. This paper presents the results of oxygen consumption rate testing (as proxy corrosion rate) of historic wrought iron samples prepared by five commonly applied surface preparation methods and subjected to high humidity environments, with outcomes assessed by use of international standards employed in industrial contexts. Results indicate that choice of surface preparation method has a direct influence on corrosion rate of the uncoated wrought iron, which impacts on performance of the protective coatings that may ultimately determine survival or loss of our rich wrought iron heritage. By implication, more extensive empirical evidence is required to underpin and develop heritage standards for treatment of wrought iron which encompass specifics of the historic material, heritage context and the ethics of conservation practice. The introduction of such standards is called for in order to bring treatment of historic ironwork in line with highly regulated engineering and industrial practices

The impact of aqueous washing on the ability of βFeOOH to corrode iron

Controlling the corrosion of historical and archaeological ferrous metal objects presents a significant challenge to conservators. Chloride is a major corrosion accelerator in coastal areas for historic ferrous metal structures and for the many chloride-containing archaeological objects within museums. Corrosion reactions involve the formation of akaganéite (βFeOOH) which incorporates chloride within its crystal structure and adsorbs it onto its surface. The mobility of the surface-adsorbed chloride in aqueous systems and atmospheric moisture means βFeOOH can itself cause iron to corrode. The extraction of chloride from βFeOOH by aqueous Soxhlet hot wash and aqueous room temperature washing is measured. The impact of this washing on the ability of βFeOOH to corrode iron is quantitatively investigated by determining the oxygen consumption of unwashed, Soxhlet-washed and room temperature-washed samples of βFeOOH mixed with iron powder and exposed to 80 % relative humidity. This acts as a proxy measurement for the corrosion rate of iron. The results are discussed relative to climatic factors for outdoor heritage objects and the treatment of archaeological iron in museums. Delivering better understanding of the properties of βFeOOH supports the development of evidence-based treatments and management procedures in heritage conservation

Measuring effectiveness of washing methods for corrosion control of archaeological iron: problems and challenges

The individual chloride content of 116 archaeological iron nails from Romano British and Medieval sites in Wales is reported. The meaning and value of chloride concentration recorded as weight of chloride in object/object weight is discussed in relation to reporting the effectiveness of washing methods designed to remove chloride from archaeological iron. This is theoretically compared to the concentration value weight of chloride in object/metal surface area of object and the difficulty of quantitatively determining the success of washing methods as stability enhancers is discussed. It is concluded that assessing the impact of residual chloride on post-treatment corrosion of archaeological objects has the potential to offer the most significant guide to treatment success

New approaches to investigating the function of mycelial networks

Fungi play a key role in ecosystem nutrient cycles by scavenging, concentrating, translocating and redistributing nitrogen. To quantify and predict fungal nitrogen redistribution, and assess the importance of the integrity of fungal networks in soil for ecosystem function, we need better understanding of the structures and processes involved. Until recently nitrogen translocation has been experimentally intractable owing to the lack of a suitable radioisotope tracer for nitrogen, and the impossibility of observing nitrogen translocation in real time under realistic conditions. We have developed an imaging method for recording the magnitude and direction of amino acid flow through the whole mycelial network as it captures, assimilates and channels its carbon and nitrogen resources, while growing in realistically heterogeneous soil microcosms. Computer analysis and modeling, based on these digitized video records, can reveal patterns in transport that suggest experimentally testable hypotheses. Experimental approaches that we are developing include genomics and stable isotope NMR to investigate where in the system nitrogen compounds are being acquired and stored, and where they are mobilized for transport or broken down. The results are elucidating the interplay between environment, metabolism, and the development and function of transport networks as mycelium forages in soil. The highly adapted and selected foraging networks of fungi may illuminate fundamental principles applicable to other supply networks

Health and Medical Researcher Publishing Patterns and How Libraries Support Them

Changing business models in scholarly publishing means that researchers have increased choices as to where to submit their articles. Choices are made on the basis of perceived quality of the journal, the speed of publishing, and how close a match there is between the journal scope and the article topic. Additionally, there is an increasing concern as to whether the journals are predatory. This paper reports on a study which sought to understand how health researchers go about selecting where to publish and the support that they receive in this regard from librarians and related staff. The research confirms that knowledge of a specific journal is still the predominant factor for researchers and that they prefer to rely on their own judgment. Librarians are providing the tools such as databases and whitelists by which better choices can be made whilst exploring new roles in advising and training researchers. Predatory journals are being selected by some, chiefly as a consequence of a lack of awareness amongst researchers and the need for some to publish swiftly and at low cost

A Series of Manganese(III) Salen Complexes as a Result of Team-Based Inquiry in a Transnational Education Programme.

The development of a team-based approach to research-led transnational practical chemistry teaching is described in which a team of five Chinese students on an articulated transnational degree programme, supported by a team of academic and technical staff, carried out a study examining the structural chemistry of a series of manganese(III) salen complexes. A series of four crystallographically characterized manganese(III) salen complexes with ancillary carboxylate ligands are reported here. The carboxylate coordination modes range from the bridging syn-anti μ2 -κO : κO' mode observed in the predominant cyclohexanoate and isobutyrate species, to a capping terminal monodentate mode for the adamantanoate species, and an unusual mixture of bridging and terminal coordination modes observed in a second minor phase of the cyclohexanoate species. The variation on extended structures based on the weakly interacting aliphatic backbones may provide a useful basis for further structural studies

Determining the probability of cyanobacterial blooms: the application of Bayesian networks in multiple lake systems

A Bayesian network model was developed to assess the combined influence of nutrient conditions and climate on the occurrence of cyanobacterial blooms within lakes of diverse hydrology and nutrient supply. Physicochemical, biological, and meteorological observations were collated from 20 lakes located at different latitudes and characterized by a range of sizes and trophic states. Using these data, we built a Bayesian network to (1) analyze the sensitivity of cyanobacterial bloom development to different environmental factors and (2) determine the probability that cyanobacterial blooms would occur. Blooms were classified in three categories of hazard (low, moderate, and high) based on cell abundances. The most important factors determining cyanobacterial bloom occurrence were water temperature, nutrient availability, and the ratio of mixing depth to euphotic depth. The probability of cyanobacterial blooms was evaluated under different combinations of total phosphorus and water temperature. The Bayesian network was then applied to quantify the probability of blooms under a future climate warming scenario. The probability of the "high hazardous" category of cyanobacterial blooms increased 5% in response to either an increase in water temperature of 0.8°C (initial water temperature above 24°C) or an increase in total phosphorus from 0.01 mg/L to 0.02 mg/L. Mesotrophic lakes were particularly vulnerable to warming. Reducing nutrient concentrations counteracts the increased cyanobacterial risk associated with higher temperatures

Disposable MMP-9 sensor based on the degradation of peptide cross-linked hydrogel films using electrochemical impedance spectroscopy

Barts and The London Charity and Queen Mary Innovation Lt