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This paper presents, for the first time, a comprehensive comparative analysis of the potential of using biochars from three distinctly different UK-sourced biomass feedstocks, produced via three different thermal processing techniques, to adsorb methylene blue dye. Biochars were made from rapeseed, whitewood, and seaweed (Laminaria Digitata), produced via hydrothermal conversion, pyrolysis, and torrefaction. Adsorption kinetic models were developed for each biochar at different temperatures, pH and initial dye concentrations. Relatively high levels of methylene blue adsorption capacity were achieved by seaweed-based biochars (∼150 mg/g), with reasonable levels for rapeseed-based biochars (∼60 mg/g), whilst adsorption levels were found to be relatively low for whitewood-based biochars (

Pilot projects in the past that have experimented with a Guaranteed Basic Income (GBI) in Manitoba and Ontario, and a recent study of the feasibility of a GBI in British Columbia, indicate that provinces are not in an ideal position to successfully implement an affordable and effective GBI. However, a GBI implemented by the federal government, financed by eliminating the GST credit and lowering personal tax exemptions, could be both effective and affordable. It could also do so without requiring the elimination of those provincial social assistance programs that are more deeply targeted toward people’s needs. By using its revenue powers, the federal government could create more fiscal capacity for the provinces to provide other cash and in-kind social supports, allowing for greater provincial benefit targeting. The federal government’s centrality in designing and implementing tax structures and collecting tax revenue make it singularly suitable for administering and delivering a GBI. Financing the GBI by eliminating the modest GST credit and lowering the current basic personal income tax exemption could provide a significant reduction in the rate, depth and intensity of poverty in Canada, without imposing an excessive tax burden on Canadians. If provinces use the GBI as a replacement for certain less-targeted provincial social assistance income transfers, the freed-up payments and reduced caseloads could also allow provinces to target more effectively those needs not addressed by the GBI. The recent COVID-19 pandemic exposed longstanding gaps in Canada’s income- support frameworks, with lower-income workers facing exceptional economic vulnerability. At the same time, the Canadian Emergency Response Benefit proved edifying in terms of how to best design a basic-income program. In addition, the federal government’s experiences with the poverty-reducing impacts of the Canada Child Benefit, the Old Age Supplement and the Guaranteed Income Supplement have moved Canada closer than ever to a workable GBI. While it comes with additional costs, those costs will be less burdensome than many GBI skeptics might believe. They must also be put into perspective, by comparing them against the costs of current and, in many cases ineffective income transfers and, just as importantly, against the human cost of leaving more Canadians living in poverty., The School of Public Policy Publications, Vol. 15 No. 1 (2022)

Microwave has become an attractive technology in the valorisation of renewable biomass and in the mitigation of challenges of climate change. In this work, the synergic effects of coupling microwave and mild conventional heating conditions has been investigated in preparing engineered ultra-micropore carbons from lignocellulosic biomass. The processing conditions were systematically investigated and correlated to the physicochemical properties of activated carbons produced and their performance in post-combustion CO2 capture. The highest CO2 uptake (225 mg g−1) was achieved for the hybrid carbon produced at low temperature (600 °C) and modest microwave intensity. The synergic effect of hybrid heating was confirmed by the significant CO2 uptake increase up to 80 and 60 % for the activated carbons prepared by microwave and conventional heating, respectively. The enhanced adsorption was confirmed by cyclic regeneration up to 99 % after 16 adsorption–desorption cycles, showing a linear correlation between the surface area, micropore volume and CO2 uptake. The Pseudo-first order model accurately describes the adsorption phenomena, indicating that physisorption is the primary mechanism governing the process. The results acquired from this study highlight the process intensification in the synthesis of porous materials with comparable properties that are typically attained in conventional heating using energy intensive conditions. Additionally, this approach reveals the benefits of conventional treatment for increasing the material's microwave susceptibility and as consequence to reduce the processing time by microwave heating. The synergic effects confirms the potential of hybrid heating for applications where fast and selective heating is paramount.

The Southern Ocean paleoceanography provides key insights into how iron fertilization and oceanic productivity developed through Pleistocene ice-ages and their role in influencing the carbon cycle. We report a high-resolution record of dust deposition and ocean productivity for the Antarctic Zone, close to the main dust source, Patagonia. Our deep-ocean records cover the last 1.5 Ma, thus doubling that from Antarctic ice-cores. We find a 5 to 15-fold increase in dust deposition during glacials and a 2 to 5-fold increase in biogenic silica deposition, reflecting higher ocean productivity during interglacials. This antiphasing persisted throughout the last 25 glacial cycles. Dust deposition became more pronounced across the Mid-Pleistocene Transition (MPT) in the Southern Hemisphere, with an abrupt shift suggesting more severe glaciations since ~0.9 Ma. Productivity was intermediate pre-MPT, lowest during the MPT and highest since 0.4 Ma. Generally, glacials experienced extended sea-ice cover, reduced bottom-water export and Weddell Gyre dynamics, which helped lower atmospheric CO2 levels., Nature Communications, 13, ISSN:2041-1723

The Southern Ocean paleoceanography provides key insights into how iron fertilization and oceanic productivity developed through Pleistocene ice-ages and their role in influencing the carbon cycle. We report a high-resolution record of dust deposition and ocean productivity for the Antarctic Zone, close to the main dust source, Patagonia. Our deep-ocean records cover the last 1.5 Ma, thus doubling that from Antarctic ice-cores. We find a 5 to 15-fold increase in dust deposition during glacials and a 2 to 5-fold increase in biogenic silica deposition, reflecting higher ocean productivity during interglacials. This antiphasing persisted throughout the last 25 glacial cycles. Dust deposition became more pronounced across the Mid-Pleistocene Transition (MPT) in the Southern Hemisphere, with an abrupt shift suggesting more severe glaciations since ~0.9 Ma. Productivity was intermediate pre-MPT, lowest during the MPT and highest since 0.4 Ma. Generally, glacials experienced extended sea-ice cover, reduced bottom-water export and Weddell Gyre dynamics, which helped lower atmospheric CO2 levels.

This study has investigated valorisation of CPH by comparing the extraction of phenolic compounds using microwave-assisted extraction (MAE) with conventional solvent extraction (CSE). Extraction time, temperature, ethanol concentration, and solvent to feed (S/F) ratio were investigated to obtain the maximum yield. The extract quality was presented as total phenolic content (TPC) which was measured by using a UV/Vis Spectrophotometer. The results showed that at a lower temperature (60 °C), MAE could produce higher TPC (107.3±1.4 mg GAE/g dw) than CSE at 70 °C (105.4±0.9 mg GAE/g dw) even when the same heating rate was applied. It can be believed that the high extraction yield on MAE is due to the selective heating effect. Results of this study suggest that MAE has potential to valorise CPH waste into valuable ingredients based on phenolic compounds.&nbsp

This study has demonstrated, for the first time, a simple, fast and flexible microwave processing method for the simultaneous preparation of bio-products (bio-oil, bio-gas and biochar) using a methodology that avoids any form of catalyst or chemical activation. The dielectric properties of biomass and physicochemical characterisation such as TGA, elemental and proximate analysis, XRD, SEM/EDX and textural properties, showed that 8 kJ g−1 of microwave energy can produce superior biochars for applications in CO2 capture. The maximum CO2 uptake capacity for biochar produced was 2.5 mmol g−1 and 2.0 mmol g−1 at 0 and 25 °C and 1 bar, which and also exhibited high gas selectivity compared with N2, fast kinetics of adsorption (95%) after 20 cycles. GC-MS analysis of generated bio-oil products revealed that higher microwave energies (>8 kJ g−1) significantly enhanced the amount of bio-oil produced (39%) and specifically the formation of levoglucosan, furfural and phenolics compounds, and bio-gas analysis identified trace levels of H2 and CH4. The results from this study confirm a green, inexpensive and efficient approach for biomass valorisation which can easily be embedded within bio-refinery process, and also demonstrates the potential of biochars for post-combustion CO2 uptake.

Southern Ocean paleoceanography provides key insights into how iron fertilization and oceanic productivity developed through Pleistocene ice-ages and their role in influencing the carbon cycle. We report the first high-resolution record of dust deposition and ocean productivity for the Antarctic Zone, close to the main dust source, Patagonia. Our deep-ocean records cover the last 1.5 Ma, thus doubling that from Antarctic ice-cores. We find a ≥10-fold increase in dust deposition during glacials and a ≤5-fold increase in ocean productivity during interglacials. This antiphasing persisted throughout the last 25 glacial cycles. Dust deposition became more widespread across the Mid-Pleistocene Transition (MPT) and, at ~0.9 Ma, dominant ice-age cycles changed from 40,000 to 100,000-years, suggesting more severe glaciations thereafter. Productivity was intermediate pre-MPT, lowest during the MPT and highest since 0.4 Ma. Glacials experienced extended sea-ice cover, reduced bottom-water export and Weddell Gyre dynamics, which helped lower atmospheric CO2 levels.

© 2020 The Authors Mesenchymal stem cells are the focus of intense research in bone development and regeneration. The potential of microparticles as modulating moieties of osteogenic response by utilizing their architectural features is demonstrated herein. Topographically textured microparticles of varying microscale features are produced by exploiting phase-separation of a readily soluble sacrificial component from polylactic acid. The influence of varying topographical features on primary human mesenchymal stem cell attachment, proliferation and markers of osteogenesis is investigated. In the absence of osteoinductive supplements, cells cultured on textured microparticles exhibit notably increased expression of osteogenic markers relative to conventional smooth microparticles. They also exhibit varying morphological, attachment and proliferation responses. Significantly altered gene expression and metabolic profiles are observed, with varying histological characteristics in vivo. This study highlights how tailoring topographical design offers cell-instructive 3D microenvironments which allow manipulation of stem cell fate by eliciting the desired downstream response without use of exogenous osteoinductive factors.

© 2020 Elsevier B.V. Polyethyleneimine (PEI)/silica adsorbents have been considered as a promising candidate for post-combustion CO2 capture, but the limited process study has been performed on a pilot-scale unit. Herein we report the 150 h continuous test results using a 100 kg sample of silica-PEI on a fluidized bed continuous unit. The CO2 removal efficiency and dynamic sorption capacity were evaluated continuously by changing a number of variables. For the sorption reactor, the changing variables were inlet H2O concentrations of 0–8.3 vol%, inlet CO2 concentrations of 12.0–21.5 vol%, bed temperatures of 50–70 °C and the bed differential pressures of 176–370 mmH2O. For the desorption reactor operated at the bed temperature of 129–130 °C, inlet H2O concentrations of 8.0–13.5 vol%, inlet CO2 concentrations of 14.6–81.2 vol% and bed differential pressures of 430–580 mmH2O were used. During continuous operation, CO2 removal efficiencies of over 90% were achieved with dynamic sorption capacities of 7.5 wt%. Solid sample collected during continuous operation were analyzed by TGA and 13C NMR to identity the decrease of CO2 adsorption capacity and the extent of thermo-oxidative side reactions. Slow oxidative degradation of the silica-PEI occurred because the transporting adsorbent was exposure to the non-humidified air in the solid transport system.

Olive pomace is a widely available agro-industrial waste residue in Europe that has the potential to contribute towards a circular, low carbon bio-economy. This study demonstrated, for the first time, the ability to successfully pyrolyse olive pomace with microwaves for the production of bio-char and bio-oil. It was found that the energy requirement needed to pyrolyse up to 80% of the olive pomace was as low as 3.6?kJ/g and bio-oil yields up to 30% were produced. Microwave power did not influence the overall yields or the chemical composition of the obtained bio-oils, but did alter the textural properties of the generated bio-chars and their ability to remove methylene blue dye. Optimum processing conditions were found to be within the 3.6?kJ/g energy requirement with a microwave power of 200?W and processing time of 180 sec. These conditions produced a bio-oil fraction containing mainly acetic acid (71.9%) and a bio-char with a surface area of 392.3?m2/g, micropore volume of 0.15?cm3/g and a methylene blue removal efficiency of 40?qMB mg/g. The results acquired from this study reveal the superiority of microwave heating in a pyrolysis system and highlight a novel and prospective route for added value recovery from natural waste resources like olive pomace.

This study presents an investigation for comparing the regeneration process of two activated carbons saturated with Basic Blue 9 (BB9) and Acid Blue 93 (AB93) using conventional (250–500 °C) and microwave heating (100–300 W). The effect of the textile dye used on the regeneration performance was analyzed by determining their dielectric properties using the perturbation cavity method from 20 to 600 °C and by TG/DTG analysis. The efficacy of the regenerated carbons was investigated by their physical properties characterized by pore structural analysis using N2 adsorption isotherms. Results showed only 3 min are required by microwaves to achieve similar textural parameters obtained by conventional heating at 190 min. The results indicate that the adsorbate plays a determining role on the regeneration efficiency as results of their interaction with the adsorbent, being easily regenerated when AB93 is the adsorbate. The adsorption capacity of microwave regenerated samples for AB93 and BB9 was 192–240 and 154–175 mg/g, respectively. Additionally, the equilibrium isotherms were simulated using the Langmuir and Freundlich isotherms models and the results suggest the textile dye removal is achieved on multilayer adsorption.

NO2, SO2 and CO2 are major air pollutants causing significant environmental and health problems. Metal-organic frameworks (MOFs), in particular [Al2(OH)2(C16O8H6)](H2O)6 (trivial names: NOTT-300/MFM-300(Al)), have shown great promise for capturing these gases. However MOF syntheses often involve toxic solvents and long durations which are inherently energy intensive, an environmental burden, and have serious safety risks. There is a pressing need to develop environmentally-friendly routes to MOFs that require less energy and implement safer solvents particularly when considering scale-up beyond the laboratory for industrial application. We report the rapid synthesis of MFM-300(Al) in aqueous conditions and 10 minutes using microwave heating. This is the fastest reported synthesis of MFM-300(Al) to date with a 99.77 % reduction in reaction time compared to the current reported 3-day conventional heated route. The microwave synthesized sub-micron crystalline material exhibits gas uptake capacities of 8.8 mmol g-1 at 273 K and 1.0 bar for CO2, 8.5 mmol g-1 at 298 K and 0.17 bar for SO2, and 1.9 mmol g-1 at 298 K and 0.01 bar for NO2. These are 26 %, 70 %, and 90 % greater for CO2, SO2, and NO2, respectively, when compared to previously reported MFM-300(Al) materials produced via a 3-day conventionally heated route demonstrating the production of high quality materials at a fraction of the time with enhanced gas properties. Crucially, this offers an opportunity to move from batch to continuous processing owing to reduced reaction times underpinned by targeted heating.

A variety of meso, meso/macro and macro-structured siliceous cellular foam (SCFs) materials have been tailor-designed and fabricated from using a modified microemulsion templating methodology with trimethyl benzene (TMB) as the pore expander and Pluronic™ block co-polymer (P123) as the surfactant, for preparing polyethyleneimine (PEI)-impregnated adsorbents for CO2 capture. The effect of preparation conditions, such as TMB/P123 mass ratio, aging temperature and aging time, on SCF morphology and pore structures and hence on the CO2 adsorption performance of the PEI-modified SCF adsorbents were investigated comprehensively. BET measurements and morphological characterisations with SEM revealed that the SCF materials prepared from using lower TMB/P123 ratios (≤ 1) and aging temperatures (≤ 100 °C) were typically meso-structured with relatively lower cell wall thicknesses but increasing the TMB/P123 ratio, aging temperature and aging times led to an transformation of the SCFs from being meso-structured into to hybrid meso/macro or even purely macro-structured nano-cellular materials with increased wall thicknesses, pore volumes and window sizes. CO2 adsorption characterisations for the PEI-impregnated SCFs demonstrated that while all the SCF materials exhibited higher capacities and faster adsorption kinetics compared to conventional meso-structured siliceous materials, the hybrid meso/macro and macro-structured SCF substrates were found to have the best CO2 adsorption performance, with uptake capacities reaching 180.2 mg-CO2/g-adsorbent (5.85 mmol/g-PEI) for PEI-600 impregnation and 198.2 mg-CO2/g-adsorbent (6.44 mmol/g-amine) for the hybrid impregnation of PEI600-TEPA at 75 °C and 0.15 bar CO2, which are significantly higher than those previously reported under similar conditions. The macro- and hybrid meso/macro-structured SCF materials were found to be particularly suitable for preparing high molecular weight PEI-modified adsorbents for greatly improved thermo-stability. At 60 wt% PEI loading, the CO2 capacity reached 126 and 97.3 mg-CO2/g-ads for PEI-10000 and PEI-60000, respectively, both showing extraordinary lifetime performance. Differing from previous findings, no particularly favourable pore diameters or windows sizes for PEI impregnation are observed for the wide range of SCF materials examined, although close to linear relationships between the CO2 uptake capacity and total pore volume appear to exist for the SCF materials with pore volumes below 2.2 cm3/g and pore diameters/window sizes ≤ 28 nm.

In this work we report a method for preparing carbon onions through microwave heating of heavy oil. It was shown that microwave heating of heavy oil mixed with a carbon catalyst at 300 W leads to the growth of a several-centimetre long fractal carbon structure in just 60 s. Scanning electron microscopy (SEM) images showed that the structure is predominantly made of networks of small particles with diameters ranging from tens to hundreds of nanometres. High-resolution transmission electron microscopy (HRTEM) images revealed the presence of disordered graphitic structures, including carbon onions with diameters as small as 30 nm. This was supported by the Raman spectroscopy which showed typical spectra for carbon onions with disordered graphitic structure. CO2 gas sorption results revealed a specific surface area of up to 164 m2/g. The carbon onions are believed to form through pyrolysis of the oil into light hydrocarbons followed by nucleation and growth of concentric graphitic layers. The carbon tree, subsequently, grew through aggregation of the carbon onions and further deposition of pyrolytic carbon, with the electric field configuration favoured the longitudinal growth of thin branches. This study demonstrates that carbon onions can be prepared from cheap unrefined liquid precursors.

High-temperature rheometry and 1H nuclear magnetic resonance (NMR) are two complementary techniques that have been used to investigate fluidity development quantitatively in the < 53 µm and 53-212 µm size fractions of high ash Indian non-coking coals and imported non-coking, medium coking and good coking coals. It was found for the 53-212 µm size fraction of the Indian bituminous coal with higher ash content (30 wt%) that, despite its high complex viscosity (> 105 Pa.s), the maximum concentration of fluid H was quite similar to that of the good coking coal (40%). This Indian non-coking coal developed fluid H with the greatest mobility (T2L > 150 μs) in the coal series, regardless of the particle size fraction studied. The probable explanation for this abnormal behavior is that the mineral matter prevents bulk movement in the sample but the local mobility of the fluid phase is still high on the nanometer scale. Blending the two Indian non-coking coals with the highly fluid medium coking coal gave higher viscosities (i.e. lower fluidity) than predicted by the polymer blend rule, probably again due to the high mineral matter restricting bulk flow. This negative effect was less pronounced with the higher ash coal suggesting that the high mobility of the fluid entities in this coal might prevent the destruction of fluid entities evolving from the medium coking coal. Partial demineralization of the high ash Indian non-coking coal to 17 wt% through a sink-float method did not decrease the complex viscosity of this coal but reduced the maximum mobility of the fluid H to levels observed with the lower ash content (20 wt%) Indian coal. Therefore, this reduction in mobility could be directly related to the mineral matter in the Indian non-coking coal.

In response to the recent focus on reducing carbon dioxide emission, the preparation and characterization of organically functionalized materials for use in carbon capture have received considerable attention. In this paper the synthesis of amine modified layered double hydroxides (LDHs) via an exfoliation and grafting synthetic route is reported. The materials were characterized by elemental analysis (EA), powder x-ray diffraction (PXRD), diffuse reflectance infrared Fourier transform spectrometer (DRIFTS) and thermogravimetric analysis (TGA). Adsorption of carbon dioxide on modified layered double hydroxides was investigated by TGA at 25–80 °C. 3-[2-(2-Aminoethylamino) ethylamino]propyl-trimethoxysilane modified MgAl LDH showed a maximum CO2 adsorption capacity of 1.76 mmol g−1 at 80 °C. The influence of primary and secondary amines on carbon dioxide adsorption is discussed. The carbon dioxide adsorption isotherms presented were closely fitted to the Avrami kinetic model.

This thesis seeks to address two questions: How does it happen that a community can evolve from a safe, vibrant neighbourhood filled with optimistic people to one that is crime-ridden and full of withdrawn individuals? And how are people born with the same hopes and dreams as the majority of American society so shaped by their experience that the majority now calls them stupid, lazy and violent? It asserts that the answers to these questions can be found in the experience of denied self and environmental efficacy felt by many persons marginalised in today's society that is oppression. Also important is the accompanying experience of internalised oppression which is the psychological state in which a person believes that him/herself and his/her social group are inferior to the dominant social group, as well as the self destructive behaviours that often contribute to a person's continued oppression and to the dominant group's view of that person as inferior (Mullaly, 2002). This thesis will suggest that the mechanism that frames the processes of oppression and of internalised oppression is the feelings of frustration that result each time a person is marginalised and discriminated against in attaining hislher goals in life. It will also suggest that the behaviours that result from this frustration can be understood using Maier's (1949) theory of frustration-instigated behaviour. Understanding oppression, internalised oppression and frustration in this way, recommendations are made for long-term social policies that address the roots of oppression rather than the destructive behaviours and in which marginalised people have control and choice. Master of Social Work (MSW)

Lyophilized protein formulations must be reconstituted back into solution prior to patient administration and in this regard long reconstitution times are not ideal. The factors that govern reconstitution time remain poorly understood. The aim of this research was to understand the influence of the lyophilization cooling profile (including annealing) on the resulting cake structure and reconstitution time. Three protein formulations (BSA 50mg/ml, BSA 200mg/ml and IgG1 40mg/ml, all in 7% w/v sucrose) were investigated after cooling at either 0.5°C/min, or quench cooling with liquid nitrogen with/without annealing. Significantly longer reconstitution times were observed for the lower protein concentration formulations following quench cool. Porosity measurements found concomitant increases in the surface area of the porous cake structure but a reduction in total pore volume. We propose that slow reconstitution results from either closed pores or small pores impeding the penetration of water into the lyophilized cake.

Activated carbon (AC) spheres with a diameter of 1.0–2.0 mm are synthesized from coal tar pitch for postcombustion carbon capture. The as-prepared AC macrospheres after KOH activation are found to possess extraordinarily developed microporosity of which 87% is ultra-microporosity with pore diameters less than 0.8 nm. Despite the relatively low surface area of just 714 m2 g−1 with a pore volume of 0.285 cm3 g−1, the macrospherical carbon adsorbents achieve exceedingly high CO2 uptake capacities of 3.15 and 1.86 mmol g−1 at 0 and 25 °C, respectively, with a CO2 partial pressure of 0.15 bar. Cyclic lifetime performance testing demonstrates that the CO2 uptake is fully reversible with fast adsorption and desorption kinetics. More importantly, due to their high bulk density of ≈1.0 g cm−3, the AC macrospheres exhibit extremely high volumetric CO2 uptakes of up to 81.8 g L−1 at 25 °C at 0.15 bar CO2, which represents the highest value ever reported for ACs. The high ultra-microporosity coupled with the potassium-modified physiochemical surface properties is found to be responsible for the outstanding CO2 adsorption performance of the pitch-based AC macrospheres.