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Growing anthropogenic greenhouse gas emissions and increasing global demand for cement are general drivers for managing greenhouse gas emissions (GHG) in the cement industry. Overall CO 2 dominates cement sector GHG emissions. The aim was to study how the management of GHG emissions in the cement production chain is related to (1) clinker substitutes, (2) primary source of energy, (3) electricity emissions, (4) technology in use and (5) geographic location. Therefore regional CO 2 emissions in the cement industry were analyzed by applying a climate impact management matrix on a cradle-to-gate basis. The use of clinker substitutes in cement varied from 3% to 36.4%. The results show that the variation of process technology and thermal energy use related CO 2 emissions is more significant than that of electricity emissions. The highest near term potential to avoid emissions is replacing clinker with mineral components (MIC). Increasing the global use of MIC to a level of 34.2%in cement would save 312 Mt CO 2 with the 2013 level of annual cement production. Similarly, a 2.7% reduction in thermal energy use would save 28 Mt CO 2 annually, and a 10% decrease of emissions from electricity use would save 26 Mt CO 2 . The best long term options from 2030 onwards are different carbon capture technologies and MgO and geopolymer cements. In addition, the CO 2 abatement costs of different investment projects were compared by using a uniform capital recovery factor. The abatement cost of avoided emissions varied from US$4 to US$ 448 per ton of CO 2 depending on the technology, geographical location and initial level of CO 2 emissions.

Recently, we have demonstrated the use of wood-derived nanocellulose papers, herein termed nanopapers, for organic solvent nanofiltration applications. In this study, we extend the use of these nanopapers to tight ultrafiltration (UF) membranes. The feasibility of such nanopaper-based UF membranes intended for use in water purification is shown. Four types of nanocelluloses, namely bacterial cellulose, wood-derived nanocellulose, TEMPO-oxidized cellulose nanofibrils and cellulose nanocrystals, were used as raw materials for the production of these nanopaper-based membranes. The resulting nanopapers exhibit a transmembrane permeance in the range of commercially available tight UF membranes with molecular weight cut-offs ranging from 6 to 25 kDa, which depends on the type of nanocellulose used. These molecular weight cut-offs correspond to average pore sizes of a few nanometres. The rejection performance of the nanopapers is on the border of nanofiltration and UF. We demonstrate that the pore size of the nanopapers can be controlled by using different types of nanocellulose fibrils.

Dogs and cats have been cohabiting with us for thousands of years. They are the major human companions. Today, dogs and cats live in urban areas. Cats and most dogs are on high carbohydrate diets and face similar life-style challenges as the human beings. The health and well-being of companion animals, just as their owners, depends on the gut microbes. Providing a proper care and nutritionally balanced diet to companion animals is recognised as a part of our responsibility to maintain the health and well being of our pet. However, as microbiota differences may facilitate exposure to pathogens and harmful environmental influences, it is prudent to search for novel tools to protect dogs and cats and at the same time the human owners from pathogens. Specific probiotic strains and/or their defined combinations may be useful in the canine and feline nutrition, therapy, and care. Probiotic supplementations have been successful in the prevention and treatment of acute gastroenteritis, treatment of IBD, and prevention of allergy in companion animals. New challenges for probiotic applications include maintenance of obesity and overweight, urogenital tract infections, Helicobacter gastritis and parasitic infections. The probiotics of human origin appear to be among the new promising tools for the maintenance of pets' health. However, the host-derived microorganisms might be the most appropriate probiotic source. Therefore, more controlled trials are needed to characterise new and safe probiotic preparations with an impact on general health and well being as well as health maintenance in dogs and cats., Highlights • The well-being of companion animals depends on the gut microbes. • Specific probiotic strains may be useful in canine and feline nutrition and care. • More trials are needed to characterise new and safe animal host-specific probiotics.

A thorough efficacy assessment was performed on three wheat straw saccharification processes including NaOH-delignification, autohydrolysis and their combination, with subsequent enzymatic hydrolysis. Instead of optimizing the process for maximal sugar yield from straw, a novel perspective is provided, allowing optimization of the overall yield against enzyme consumption and reaction volume. At total sugar yields above 60%, NaOH-delignification was the most efficient in terms of enzymatic and volumetric productivity, whereas at lower yields, autohydrolysis showed a comparable enzymatic and a higher volumetric productivity. The double treatment led to improved hydrolysability compared to autohydrolysis, but was the least productive due to reduced solid yields. A threshold in the delignification efficiency between 3% and 6% NaOH-loadings per straw DM resulted from the depletion of alkalinity by the released organic acids. A novel rational function model was developed for the total sugar yield, which is generally superior for describing asymptotic behaviour compared to conventional polynomial models in response surface modelling.

Stereolithography (SLA) holds great promise in the fabrication of cell-laden hydrogels with biomimetic complexity for use in tissue engineering and pharmaceutics. However, the availability of biodegradable photocrosslinkable hydrogel polymers for SLA is very limited. In this study, a water-soluble methacrylated poly(ethylene glycol-co-depsipeptide) was synthesized to yield a biodegradable photocrosslinkable macromer for SLA. Structural analysis confirmed the inclusion of biodegradable peptide and ester groups and photocrosslinkable methacrylate groups into the polymer backbone. The new macromer combined with the RGDS peptide was used for the SLA fabrication of hydrogels in the absence and the presence of cells. With the increasing light exposure time in SLA, the mechanical stiffness of the hydrogels increased from 3 ± 1 kPa to 38 ± 13 kPa. The total mass loss of the samples within 7 days in PBS was 13–21% and within 24 days was 35–66%. Due to degradation, the mechanical stiffness decreased by one order magnitude within 7-day incubation in PBS. Encapsulated endothelial cells proliferated in the hydrogels during the 10-day in vitro cell culturing study. The macromer was further used in SLA to fabricate bifurcating tubular structures as preliminary vessel grafts. The new biodegradable, photocrosslinkable polymer is a significant addition to the very limited material selection currently available for the SLA-based additive manufacturing of cell-laden tissue engineering constructs.

Steam reforming (SR) and autothermal reforming (ATR) of n-butanol was studied over 0.5 wt% Rh/ZrO2 catalyst at 500, 600 and 700 °C, atmospheric pressure, steam to carbon (S/C) molar ratio of 4 and oxygen to carbon (O2/C) molar ratio of 0.1. The influence of the O2/C ratio on performance was also carried out at 500 °C. Catalyst performance, i.e. conversion, product distribution and short-term stability, was compared with plain ZrO2 support to derive a reaction network, including contributions of reactions in the gas phase, on the support and on Rh. At 500 and 600 °C the catalyst deactivated very rapidly for WGS and hydro-isomerization reactions, slightly less rapidly for reforming and significantly slower for dehydration and dehydrogenation reactions. Increasing temperature and oxygen concentration improved catalyst stability. Rh/ZrO2 showed promising performance at 700 °C with complete conversion and hydrogen yield, 70% of theoretical maximum, decreasing over 21 h with not more than 8 and 1% for SR and ATR, respectively. Deactivation of the catalyst for reforming is caused by carbon deposition on and near the Rh particles. At 700 °C, coke forms via gas phase reactions, while catalytic reactions on the surface mainly contribute at 500 and 600 °C

The objective of this work is to assess the exergoeconomic performance of three biomass upgrading processes, namely wood pellets, torrefied wood pellets and pyrolysis slurry (a mixture of pyrolysis char and oil), integrated with a municipal combined heat and power plant. The work is a continuation of work published earlier (Kohl et al., 2013) and the same simulation model results are used as input for the calculation of the exergy flows within the system. Economic data of the assessed processes has been obtained from the literature and has been combined with the exergy data following the specific exergy costing approach in order to perform the exergoeconomic analysis. The highest exergy destruction is caused in the combustion equipment, whereas the upgrading processes appear highly efficient. The systems’ exergetic efficiency can be improved by 22%, 26% and 31% for the integration with pyrolysis slurry, torrefied wood pellets and wood pellets, respectively, making wood pellets the most efficient integration option. However, the integration of pyrolysis slurry production yields the highest profit under the projected price scenario. In addition it also reacts moderately on possible price fluctuations as is shown in a sensitivity analysis. Considering the generally acknowledged future technical potential of pyrolysis products for replacing fossil oil-based products transport fuel production as well as the commonly expected further price increase for fossil oil, pyrolysis slurry constitutes as the best option to be integrated with the municipal combined heat and power plant.

Hybrid composite films of nanofibrillated cellulose (NFC), cationic hydroxyethylcellulose (CHEC) and glycerol were prepared via solution blending. NFC adopted a fibrillar structure, being coated with the CHEC moieties. Ionic interactions between NFC and CHEC were present, as confirmed by FTIR, leading to enhanced strength, moduli and work-to-break values. Simultaneously, segments of non-cationic HEC worked in tandem with glycerol to lubricate the cellulose nanofibrils, yielding maximum strain-at-break values of 141%. The NFC–CHEC–glycerol films were subsequently coated with a 4.5–6 μm layer of poly(propylene carbonate) (PPC), microscopy confirming effective coating of NFC at the composite-coating layer boundary. The hydrophobic nature of PPC enhanced water stability for acute time periods and increased contact angle values. Film strength and toughness was also enhanced by PPC, indicative of its reinforcing ability. The hybrid composites highlight the ability to prepare extremely ductile cellulose-based films, with the aforementioned materials being amongst the most ductile cellulose-based and/or cellulose-majority films documented.

To reduce greenhouse gas emissions, more sustainable sources of energy, fuel and chemicals are needed. Biomass side streams such as black liquor, which is a by-product of pulp production, has the potential to be used for this purpose. The aim of the study was the production of carboxylic acids, such as lactic acid, formic acid and acetic acid, from kraft and non-wood black liquor. The processes studied were partial wet oxidation (PWO) and catalytic partial wet oxidation (CPWO). The results show that the yield of carboxylic acid is higher when treated by PWO than the results from CPWO at temperatures of 170°C and 230°C. The results shows that the PWO process can increase the yield of carboxylic acids and hydroxy acids in black liquor, reduce lignin content and decrease pH, which makes further separation of the acids more favourable. The hydroxy acids are valuable raw materials for biopolymers, and acetic acid and formic acid are commonly used chemicals conventionally produced from fossil feedstock.