The Experts below are selected from a list of 246105 Experts worldwide ranked by ideXlab platform
Bjorn Vinneras - One of the best experts on this subject based on the ideXlab platform.
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process efficiency and ventilation requirement in black soldier fly larvae composting of substrates with High Water Content
Science of The Total Environment, 2020Co-Authors: Cecilia Lalander, Evgheni Ermolaev, Viktoria Wiklicky, Bjorn VinnerasAbstract:In order to transition from a linear to a circular economy in the organic waste management sector, more of the elements in waste need to be recycled. Use of black soldier fly (Hermetia illucens L.; Diptera: Stratiomyidae) larvae (BSFL) for organic waste treatment has potential to harvest more complex molecules than conventional methods. Many organic waste substrates have High Water Content (>80%), but the impact on BSFL treatment efficiency of substrate Water Contents >80% is not known. This study evaluated the impact of High Water Content food waste on BSFL composting efficiency in terms of waste-to-biomass conversion ratio, material reduction, larval survival and the ventilation required for enabling dry separation of larvae from residue. In total, six Water Contents ranging from 76% to 97.5% were evaluated in two experimental trials. It was found that increasing Water Content reduced biomass conversion ratio and survival rate of the larvae, from 33.4% of volatile solids (VS) and 97.2% survival in 76% Water to 17.5% of VS and 19.3% survival in 97.5% Water. Furthermore, we found that the ventilation requirement for achieving dry separation of larvae from residue could be modelled by estimating the amount of Water that would need to be removed, taking into account the Water bound in the larvae, and knowing the specifics of the ventilation set-up of the modelled system. The findings could have implications on the waste management sector interested in implementing BSFL treatment, as the findings demonstrate that it is possible to treat wet substrates (such as fruit and vegetable wastes) without any pre-treatment other than grinding and attain an adequately dry residue for enabling dry separation of the larvae from the residue.
Takuzo Aida - One of the best experts on this subject based on the ideXlab platform.
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High Water Content clay nanocomposite hydrogels incorporating guanidinium pendant methacrylamide tuning of mechanical and swelling properties by supramolecular approach
Journal of Polymer Science Part A, 2014Co-Authors: Masataka Ohtani, Shingo Tamesue, Yasuhiro Ishida, Takuzo AidaAbstract:Novel clay–polymer composite hydrogels with High Water Content (up to 98 wt %) are developed, in which mechanical properties are reinforced by the formation of multiple ion-pairs between the polymer chains and clay nanosheets (CNS). When a small amount of guanidinium-pendant methacrylamide (0.1–0.2 wt %) is copolymerized with a neutral monomer (0.5–2.0 wt %) in an aqueous dispersion of CNS (1.0–3.0 wt %), a self-standing hydrogel with satisfactory mechanical toughness and elasticity results, despite its High Water Content (95–98 wt %). The mechanical properties and swelling behaviors of the hydrogels can be tuned by the amount of the guanidinium-pendant acrylamide. A systematic study indicates that the ion pairs, formed between the guanidinium groups in the polymer chains and the oxyanions on the surfaces of the CNS, serve as crosslinking points in the three-dimensional network developed in these hydrogels. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 839–847
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High Water Content mouldable hydrogels by mixing clay and a dendritic molecular binder
Nature, 2010Co-Authors: Qigang Wang, Justin L Mynar, Masaru Yoshida, Kou Okuro, Kazushi Kinbara, Takuzo AidaAbstract:Hydrogels are mouldable polymeric materials made mostly of Water, used for example as cell tissue cultures and in prosthetics. Hydrogels held together by non-covalent interactions usually have poor mechanical properties, whereas the rather stronger covalently bonded hydrogels cannot self-heal if cut and tend to be brittle. The idea that Water-based hydrogels might be developed as environmentally friendly substitutes for conventional petroleum-based plastics in some applications, bringing novel properties with them, comes a little closer with the development of a supramolecular (non-covalent) hydrogel that is a solid thanks to the presence of small quantities of non-Water ligands — 3% clay and tiny amounts of an organic binder. This new gel is capable of self-healing, is exceptionally resilient and can be moulded into free-standing shapes that can also be fused together to form more complex architectures. In the search to reduce our dependency on fossil-fuel energy, new plastic materials that are less dependent on petroleum are being developed, with Water-based gels — hydrogels — representing one possible solution. Here, a mixture of Water, 3% clay and a tiny amount of a special organic binder is shown to form a transparent hydrogel that can be moulded into shape-persistent, free-standing objects and that rapidly and completely self-heals when damaged. With the world’s focus on reducing our dependency on fossil-fuel energy, the scientific community can investigate new plastic materials that are much less dependent on petroleum than are conventional plastics. Given increasing environmental issues, the idea of replacing plastics with Water-based gels, so-called hydrogels, seems reasonable. Here we report that Water and clay (2–3 per cent by mass), when mixed with a very small proportion (<0.4 per cent by mass) of organic components, quickly form a transparent hydrogel. This material can be moulded into shape-persistent, free-standing objects owing to its exceptionally great mechanical strength, and rapidly and completely self-heals when damaged. Furthermore, it preserves biologically active proteins for catalysis. So far1 no other hydrogels, including conventional ones formed by mixing polymeric cations and anions2,3 or polysaccharides and borax4, have been reported to possess all these features. Notably, this material is formed only by non-covalent forces resulting from the specific design of a telechelic dendritic macromolecule with multiple adhesive termini for binding to clay.
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High Water Content mouldable hydrogels by mixing clay and a dendritic molecular binder
Nature, 2010Co-Authors: Qigang Wang, Justin L Mynar, Masaru Yoshida, Kou Okuro, Kazushi Kinbara, Eunji Lee, Myongsoo Lee, Takuzo AidaAbstract:With the world's focus on reducing our dependency on fossil-fuel energy, the scientific community can investigate new plastic materials that are much less dependent on petroleum than are conventional plastics. Given increasing environmental issues, the idea of replacing plastics with Water-based gels, so-called hydrogels, seems reasonable. Here we report that Water and clay (2-3 per cent by mass), when mixed with a very small proportion (<0.4 per cent by mass) of organic components, quickly form a transparent hydrogel. This material can be moulded into shape-persistent, free-standing objects owing to its exceptionally great mechanical strength, and rapidly and completely self-heals when damaged. Furthermore, it preserves biologically active proteins for catalysis. So far no other hydrogels, including conventional ones formed by mixing polymeric cations and anions or polysaccharides and borax, have been reported to possess all these features. Notably, this material is formed only by non-covalent forces resulting from the specific design of a telechelic dendritic macromolecule with multiple adhesive termini for binding to clay.
Carolyn A. Koh - One of the best experts on this subject based on the ideXlab platform.
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Investigating Gas Hydrate Formation in Moderate to High Water Cut Crude Oil Containing Arquad and Salt, Using Differential Scanning Calorimetry
2016Co-Authors: Chenwei Liu, Vishal K. Srivastava, Carolyn A. KohAbstract:Gas hydrate formation can result in the blockage of deepWater flowlines, leading to severe economic and safety risks. As oil and gas production moves to greater Water depths, the operating conditions of High pressure and low temperature can lead to greater risks of hydrate formation in the flowlines. In addition, as the fields mature, the continuous increase of Water cut further enhances the potential problems associated with hydrate formation. With these more challenging production conditions, antiagglomerants could offer an economical and environmentally attractive alternative for preventing hydrate plug formation. However, reported work on hydrate antiagglomerant behavior for moderate to High Water Content systems is quite limited. The work reported in this paper investigates the effects of Arquad 2HT-75 (used as a model antiagglomerant) and salt (NaCl) on Water-in-oil emulsions, and explores the gas hydrate formation characteristics for moderate to High Water Content (50 and 75 vol %) crude oil using High-pressure differential scanning calorimetry (DSC). The results indicate that the formation and dissociation of both ice and hydrate could lead to destabilization of the Water-in-oil emulsion under certain conditions. At a High Water cut (75 vol %), hydrate conversion is much lower, because of mass-transfer limitations for hydrate formation. Furthermore, the DSC and bottle tests also suggest that, at the concentrations and conditions used in this work, the addition of salt to Arquad 2HT-75 can help to form stable Water-in-oil emulsions
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hydrate formation from High Water Content crude oil emulsions
Chemical Engineering Science, 2008Co-Authors: David Greaves, John A Boxall, James Mulligan, Dendy E Sloan, Carolyn A. KohAbstract:Methane hydrate formation and dissociation studies from High Water Content (>60vol% Water) – crude oil emulsions were performed. The hydrate and emulsion system was characterized using two particle size analyzers and conductivity measurements. It was observed that hydrate formation and dissociation from Water-in-oil (W/O) emulsions destabilized the emulsion, with the final emulsion formulation favoring a Water continuous state following re-emulsification. Hence, following dissociation, the W/O emulsion formed a multiple o/W/O emulsion (60 vol% Water) or inverted at even Higher Water cuts, forming an oil-in-Water (O/W) emulsion (68 vol% Water). In contrast, hydrate formation and dissociation from O/W emulsions (⩾71vol% Water) stabilized the O/W emulsion.
Xiaoya Bian - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation on effect of curing stress on the strength of cement stabilized clay at High Water Content
Acta Geotechnica, 2017Co-Authors: Rongjun Zhang, Junjie Zheng, Xiaoya BianAbstract:The application of cement-stabilized marine clay at High Water Content (HW-CSC) as land reclamation fill has been receiving increasing attention and popularity. In current coastal development, HW-CSC land reclamation projects begin to advance toward deeper Water areas, leading to greater filling heights and thus Higher curing stresses acting on the lower portions of HW-CSC. In principle the Higher curing stress will improve the strength gain of HW-CSC, but this curing stress effect is not taken into account in current design practice. This study aims to bridge the gap. Fifteen different mixes of HW-CSC are first prepared and cured in consolidation tubes for seven days under various curing stresses. Their strengths and some other post-curing parameters are then tested and analyzed to demonstrate the quantitative effect of curing stress on the strength gain of HW-CSC. Results indicate that the strength gain of HW-CSC is significantly influenced by the curing stress; however, the effect of curing stress cannot be simply replaced by reducing the remolding Water Content during mixing stage and letting the specimens be cured under atmospheric stress condition. Therefore, it is concluded that the effect of curing stress includes two different components—a consolidation effect and another effect termed the “self-stress” effect in this study. Finally, an empirical relationship accounting for the combined effects of mixing proportion and curing stress is developed for characterization of the strengths of HW-CSCs with different mixing proportions and various curing stresses. The proposed relationship is validated by three independent data groups collected from the literature. This empirical relationship can be helpful in optimization of mixing proportions of HW-CSC used for land reclamation purpose.
Cecilia Lalander - One of the best experts on this subject based on the ideXlab platform.
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process efficiency and ventilation requirement in black soldier fly larvae composting of substrates with High Water Content
Science of The Total Environment, 2020Co-Authors: Cecilia Lalander, Evgheni Ermolaev, Viktoria Wiklicky, Bjorn VinnerasAbstract:In order to transition from a linear to a circular economy in the organic waste management sector, more of the elements in waste need to be recycled. Use of black soldier fly (Hermetia illucens L.; Diptera: Stratiomyidae) larvae (BSFL) for organic waste treatment has potential to harvest more complex molecules than conventional methods. Many organic waste substrates have High Water Content (>80%), but the impact on BSFL treatment efficiency of substrate Water Contents >80% is not known. This study evaluated the impact of High Water Content food waste on BSFL composting efficiency in terms of waste-to-biomass conversion ratio, material reduction, larval survival and the ventilation required for enabling dry separation of larvae from residue. In total, six Water Contents ranging from 76% to 97.5% were evaluated in two experimental trials. It was found that increasing Water Content reduced biomass conversion ratio and survival rate of the larvae, from 33.4% of volatile solids (VS) and 97.2% survival in 76% Water to 17.5% of VS and 19.3% survival in 97.5% Water. Furthermore, we found that the ventilation requirement for achieving dry separation of larvae from residue could be modelled by estimating the amount of Water that would need to be removed, taking into account the Water bound in the larvae, and knowing the specifics of the ventilation set-up of the modelled system. The findings could have implications on the waste management sector interested in implementing BSFL treatment, as the findings demonstrate that it is possible to treat wet substrates (such as fruit and vegetable wastes) without any pre-treatment other than grinding and attain an adequately dry residue for enabling dry separation of the larvae from the residue.