ContaminatEd land remediation through energy crops for soil improvement to liquid biofuel strategies : [making sustainable biofuels on formerly contaminated land]

Aim : CERESiS aims to develop, assess and validate integrated biofuel production pathways linking land decontamination to appropriate bioenergy crops and environmentally & economically efficient advanced biofuel production. Objective 1 : Demonstrate the suitability and effectiveness of various conventional and novel species of energy crops for phytoremediation purposes in contaminated land , against a variety of the most common contaminants globally. Objective 2 : Demonstrate the potential of two novel thermochemical processes , i.e. Supercritical Water Gasification (SCWG) and Fast Pyrolysis (FP), for the production of biofuels and key biofuel precursors. Objective 3: Provide decision support to stakeholders and policy makers in order to achieve optimal win win solutions for site specific land decontamination through phytoremediation while simultaneously producing clean liquid biofuels

Raman Quantum Memory with Built-In Suppression of Four-wave Mixing Noise

Quantum memories are essential for large-scale quantum information networks. Along with high efficiency, storage lifetime and optical bandwidth, it is critical that the memory add negligible noise to the recalled signal. A common source of noise in optical quantum memories is spontaneous four-wave mixing. We develop and implement a technically simple scheme to suppress this noise mechanism by means of quantum interference. Using this scheme with a Raman memory in warm atomic vapour we demonstrate over an order of magnitude improvement in noise performance. Furthermore we demonstrate a method to quantify the remaining noise contributions and present a route to enable further noise suppression. Our scheme opens the way to quantum demonstrations using a broadband memory, significantly advancing the search for scalable quantum photonic networks.Comment: 6 pages, 5 figures plus Supplementary Materia

Ultrahigh and persistent optical depths of caesium in Kagom\'e-type hollow-core photonic crystal fibres

Alkali-filled hollow-core fibres are a promising medium for investigating light-matter interactions, especially at the single-photon level, due to the tight confinement of light and high optical depths achievable by light-induced atomic desorption. However, until now these large optical depths could only be generated for seconds at most once per day, severely limiting the practicality of the technology. Here we report the generation of highest observed transient ($>10^5$ for up to a minute) and highest observed persistent ($>2000$ for hours) optical depths of alkali vapours in a light-guiding geometry to date, using a caesium-filled Kagom\'e-type hollow-core photonic crystal fibre. Our results pave the way to light-matter interaction experiments in confined geometries requiring long operation times and large atomic number densities, such as generation of single-photon-level nonlinearities and development of single photon quantum memories.Comment: Author Accepted versio

Tomography of photon-number resolving continuous-output detectors

We report a comprehensive approach to analysing continuous-output photon detectors. We employ principal component analysis to maximise the information extracted, followed by a novel noise-tolerant parameterised approach to the tomography of PNRDs. We further propose a measure for rigorously quantifying a detector's photon-number-resolving capability. Our approach applies to all detectors with continuous-output signals. We illustrate our methods by applying them to experimental data obtained from a transition-edge sensor (TES) detector.Comment: 5 pages, 3 figures, also includes supplementary informatio

A circular economy approach to drinking water treatment residue management in a catchment impacted by historic metal mines

Drinking water treatment residues (DWTR) from mining areas which remove and contain potentially toxic elements (PTE) could still potentially be used as a soil amendment to restore contaminated sites in the same catchment, thus eliminating waste and reducing the chemical and physical mobility of the pollutants. To assess this restorative and regenerative approach to DWTR management, field and pot trials were established with soils from a historic Pb–Zn mine site in the North East of England, amended with either local DWTR or the nearest available municipal green waste compost (GWC). Soils from the mine site were found to have very low levels of nutrients and very high levels of PTE (Pb and Zn > 13, 000 mg/kg). The perennial grass species Phalaris arundinacea, known for many ecosystem service benefits including soil stabilization, was used throughout this study. The application of the BCR sequential extraction to soils amended with the DWTR in the pot trials found a significant decrease in the bioavailability of Pb and Cu (p MIX > DWTR (p < 0.05). Results of the elemental analysis of biomass from the field trial were generally ambiguous and did not reflect the decreased bioavailability noted in the pot trials using the BCR procedure. Pot trials, however, showed increases in plant growth and decreases in concentrations of Cr, Cu, Pb and Zn in above ground biomass following the application of both amendments. Further work should involve the testing of a mixture of DWTR and other soil amendments to enhance plant growth. The success of these trials should provide confidence for those working in drinking water treatment and catchment management to reuse the waste residues in a circular economy and a sustainable way that could improve water quality over time

A two-way photonic interface for linking Sr+ transition at 422 nm to the telecommunications C-band

We report a single-stage bi-directional interface capable of linking Sr+ trapped ion qubits in a long-distance quantum network. Our interface converts photons between the Sr+ emission wavelength at 422 nm and the telecoms C-band to enable low-loss transmission over optical fiber. We have achieved both up- and down-conversion at the single photon level with efficiencies of 9.4% and 1.1% respectively. Furthermore we demonstrate noise levels that are low enough to allow for genuine quantum operation in the future.Comment: 5 pages, 4 figure

Chemical and biological tests to assess the viability of amendments and Phalaris arundinacea for the remediation and restoration of historic mine sites

Inadequate waste disposal practices at historic mining sites around the world have resulted in significant areas impacted by potentially toxic elements (PTE) [1]. Historic mining tailings and spoil are typically too physically, chemically and biologically deficient for spontaneous vegetation, allowing the redistribution of contaminated soils, mobilized through processes such as areolation and the movement water [2]. In-situ biological and chemical stabilisation of sites is increasingly considered the best option when managing the risks associated with historic mining [1]. Studies have shown that the immobilization of PTEs can be achieved through the use of low leaching waste amendments capable of adsorption, precipitation and complexation reactions, resulting in the redistribution of contaminants from solution phase to solid phase, thereby reducing their bioavailability and mobilization potential within the environment [2–4] and promoting plant growth and physical stabilisation. Recent research in the Upper River Derwent, NE England (Lord, pers. com.) has highlighted the contribution of historic mining and mineral processing areas as sources of particulate and dissolved PTEs entering river sediments. Subsequent analysis of mining and mineral processing sites has confirmed the presence of significant Cd, Pb and Zn concentrations in loose spoil, tailings and unvegetated soils. The aim of this study is to evaluate the potential of several organic amendments and a perennial native grass species, Reed Canarygrass (RCG) (Phalaris arundinacea), to immobilize and stabilise contaminated soils [5,6]. This plant was selected for its ability to rapidly colonize and establish on contaminated soils whilst not (usually) accumulating high levels of PTEs or thereby adding to dispersion [5,6]. A combination of biological and chemical approaches will be used to analyse the efficacy of the different amendments throughout this study. These include the use of the modified BCR sequential extraction procedure and single extractants to assess PTE bioavailability, the monitoring of changes in soil properties such as OM, pH and CEC and the measurement of above ground biomass after a 12-week growth period. Although several recent studies have conducted similar pot trials, very few have applied their results to actual field trials, a recommendation commonly made in key literature reviews [1]. The results of our experiments will used to implement a two-year phytoremediation trial at a former mine site beginning in Spring 2019. [1] Bolan N, Kunhikrishnan A, Thangarajan R, Kumpiene J, Park J, Makino T, et al. Journal of Hazardous Materials. (2014) 266:141-166 [2] Rodríguez L, Gómez R, Sánchez V, Alonso-Azcárate J.. Environ Sci Pollut Res. (2016) 23:6046-6054 [3] Alvarenga P, Gonçalves AP, Fernandes RM, de Varennes A, Vallini G, Duarte E, et al.. Sci Total Environ. (2008) 406:43-56 [4] Badmos BK, Sakrabani R, Lord R.. Arch Agron Soil Sci. (2015) 62:865-876 [5] Jensen EF, Casler MD, Farrar K, Finnan JM, Lord R, Palmborg C, et al. 5 –In: Perennial Grasses for Bioenergy and Bioproducts. (2018) 5:153-173 [6] Lord RA. Biomass and Bioenergy. (2015) 78;110-12

The effects of organic waste soil amendments on above ground biomass of Reed Canary Grass (Phalaris arundinacea) grown at a historic Pb-F-Zn mine site

Historic metal mine tailings and spoil are typically too physically, chemically and biologically deficient for spontaneous revegetation. Studies focusing on the Upper River Derwent have highlighted the contribution of historic mining and mineral processing areas as sources of particulate and dissolved potentially toxic elements (PTE) entering river sediments. This study will conduct a two year field trial that aims to evaluate the potential of two organic waste soil amendments and a perennial native grass species, to immobilize PTE and stabilise impacted soils. In-situ biological and chemical stabilisation is increasingly considered the best option when managing the risks associated with historic mining [1]

Chemical and biological tests to assess the viability of amendments and Phalaris arundinacea for the remediation and restoration of historic mine tailings.

Recent research in the Upper River Derwent, NE England highlighted the contribution of historic mining and mineral processing areas as sources of particulate and dissolved potentially toxic elements (PTE) entering river sediments. Subsequent analysis of mining and mineral processing sites has confirmed the presence of significant Cd, Pb and Zn concentrations in loose spoil, tailings and unvegetated soils. The aim of this study is to evaluate the potential of several organic amendments and a perennial native grass species, reed canary grass (Phalaris arundinacea), to immobilize PTEs and stabilise contaminated soils. The plant specie was selected for its ability to rapidly colonize and establish on contaminated soils whilst not (usually) accumulating high levels of PTEs or thereby adding to dispersion. Preliminary pot trials using bulk samples of mine spoil and amendments are currently ongoing following an adapted British Standards (BS/EN 11269-2:2013) method for the effects of PTEs on above ground plant growth. A combination of biological and chemical approaches will be used to analyse the efficacy of the different amendments throughout this study. These include the use of the modified BCR sequential extraction procedure and single extractants to assess PTE bioavailability, the monitoring of changes in soil properties such as OM, pH and CEC and the measurement of above ground biomass after a 12-week growth period. Although several recent studies have conducted similar pot trials, very few have applied their results to actual field trials. The results of these experiments will used to implement a two-year phytoremediation trial at a former mine site beginning in Spring 2019