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Abstract Bio-based polyurethane (BPU) foams were successfully prepared using hydrothermally liquefied wheat straw (WS) to substitute a mass fraction of up to 50% of polyols. Response surface methodology (RSM) based on central composite design (CCD) was employed to optimize four process parameters: NCO/OH molar ratio, loading of crosslinking agent (glycerol), loading of catalyst (a mixture of triethylene diamine, stannous octoate, and triethanolamine), and loading of blowing agent (water) for the maximum compression strength of the rigid BPU foams. With the quadratic orthogonal regression model, verified by experimentation, the maximum compression strength of approximately 180 kPa was obtained at the following optimal conditions: NCO/OH molar ratio of 1.24:1, glycerol addition of 12.11%, catalyst loading of 0.76%, and blowing agent addition of 1.31% in relation to the total mass of polyols. The BPU foam prepared at the optimal conditions exhibits good thermal conductivity (0.045 Wm−1K−1) and thermal stability, comparable to those of a reference foam prepared with 100% PPG400.

Abstract. The impact of multiphase reactions involving nitrogen dioxide (NO2) and aromatic compounds was simulated in this study. A mechanism (CAPRAM 2.4, MODAC Mechanism) was applied for the aqueous phase reactions, whereas RACM was applied for the gas phase chemistry. Liquid droplets were considered as monodispersed with a mean radius of 0.1 µm and a liquid content (LC) of 50 µg m-3. The multiphase mechanism has been further extended to the chemistry of aromatics, i.e. reactions involving benzene, toluene, xylene, phenol and cresol have been added. In addition, reaction of NO2 with dissociated hydroxyl substituted aromatic compounds has also been implemented. These reactions proceed through charge exchange leading to nitrite ions and therefore to nitrous acid formation. The strength of this source was explored under urban polluted conditions. It was shown that it may increase gas phase HONO levels under some conditions and that the extent of this effect is strongly pH dependent. Especially under moderate acidic conditions (i.e. pH above 4) this source may represent more than 75% of the total HONO/NO2 - production rate, but this contribution drops down close to zero in acidic droplets (as those often encountered in urban environments).

Abstract Canada has numerous climatic and geographical regions and the Canadian housing stock (CHS) is diversified in terms of vintage, geometry, construction materials, envelope, occupancy, energy sources and heating, ventilation and air conditioning system and equipment. Therefore, strategies to achieve net zero energy (NZE) status with the current stock of houses need to be devised considering the unique characteristics of the housing stock, the economic conditions and energy mix available in each region. Identifying and assessing pathways for converting existing houses to NZE buildings at the housing stock level is a complex and multifaceted problem and requires extensive analysis on the impact of energy efficiency and renewable/alternative energy technology retrofits on the energy use and GHG emissions of households. A techno-economic analysis of retrofitting renewable/alternative energy technologies in the CHS to reduce energy consumption and GHG emissions was conducted to develop strategies to achieve or approach NZE status for Canadian houses. The results indicate that substantial energy savings and GHG emission reductions are techno-economically feasible for the CHS through careful selection of retrofit options. While achieving large scale conversion of existing houses to NZEB is not feasible, approaching NZE status is a realistic goal for a large percentage of Canadian houses.

The net energy (NE) system takes into account the metabolic utilisation of energy and has been proposed as a superior system for characterising the energy value of feeds. In growing pigs, the inefficiency of ME utilisation for NE (or the heat increment, HI) is dependent on many factors, among them the genotype, which implies that published NE prediction equations may not apply across all genotypes. We conducted a study to investigate the effect of two genotypes (Yorkshire-Hampshire♀ × Duroc♂; YH × D) and Large white♀ × Landrace♂; LW × LR) on heat production (HP) and NE value of a corn soybean meal-based diet fed to growing pigs. The diet met or exceeded the nutrient specifications of 20-50 kg b.w. pigs according to NRC (1998). A total of sixteen barrows were used, eight of each genotype (initial b.w. of 20.1 ± 1.1 and 19.0 ± 0.9 kg for YH ×D and LW × LR, respectively). Pigs were initially fed at 550 kcal/kg b.w.-0.60/day (high ME intake) for determination of DE and ME in metabolism crates. Thereafter, HP was measured using an indirect calorimeter at either high ME or 330 kcal/kg b.w.-0.60/day (low ME intake) to estimate fasting HP (FHP) by regression. Pigs were allowed a 3-d adaptation period at low ME intake before measurement of HP. Irrespective of the genotype, a reduction of ME intake resulted in a decrease (P < 0.0001) of HP (352 for high ME vs. 292 kcal/kg b.w.-0.60/day for low ME). Pigs of LW × LR tended (P = 0.07) to have higher HP than those of YH× D and their estimated FHP was 175 and 103 kcal/kg b.w.-0.60/day, respectively. The determined diet NE value was lower for the YHxD genotype (2,307 vs. 2633 kcal/kg DMI, P = 0.01) than for the LW × LR genotype. Pigs of LW × LR genotype showed lower (179 vs. 226 kcal/kg b.w.-0.60/day, P = 0.003) HI than YH × D genotype and were determined to retain less energy as protein (100 vs. 123 kcal/kg b.w.-0.60/day, P =0.04) and more energy as fat (73 vs. 42 kcal/kg b.w.-0.60/day, P = 0.04). The diet NE value was 96% (LW × LR) and 81% (YH × D) of the predicted NE from published equations. In conclusion, a corn-soybean meal fed at equal amounts resulted in different HP and NE value depending on genotype.

Even with the benefits of sustainability and climate change reporting, there is limited information on how municipalities are reporting on performance for external stakeholders in comparison with private sector organizations. The purpose of this research was to gain an understanding of the current state of sustainability and climate change reporting at the local level and to investigate the extent to which municipalities across Ontario, Canada, report. We used content analysis to identify the presence or non-presence of information on the websites of 38 municipalities and analyzed the results using descriptive statistics. Our analysis showed that the sample municipalities were not widely reporting on sustainability or climate change performance. Also, we identified a gap between the number of plans and reports produced by sample municipalities, with the latter being less common, indicating a need for an improved evaluation of plan implementation. Further, we found that a provincial regulation that required municipalities to make their energy conservation and demand management plans public did not guarantee publication of the plan on a municipality’s website. This study contributes to the growing field of sustainability and climate change planning and reporting by local governments and offers empirical evidence specific to Ontario, Canada.

This work presents a new method to evaluate generation reserve margins in systems with renewable sources. In assessing the adequacy of generation reserve amounts, besides failures in generating units, their capacity intermittencies, unavailability, and capacity limits of the transmission system are duly considered. Risk indices are evaluated using quasi-sequential Monte Carlo simulation techniques. The cross-entropy method is used to treat rare events and also to identify critical equipment for operation in each scenario. The proposed method is applied to the original IEEE RTS system and to a modified configuration with insertion of wind power plants. A subsystem of the Brazilian interconnected network is also used to illustrate the practicality of the proposed method.

Abstract Bitumen is too viscous to be produced by conventional recovery methods and significant amounts are too deep to be recovered by mining, necessitating enhanced in-situ oil recovery techniques. The majority of operating and planned in-situ bitumen projects employ thermal techniques to lower the bitumen's viscosity, allowing it to be produced. The viscosity characteristics of the bitumen consequently have a significant effect on production rates and recovery. Bitumen viscosity and chemical composition variation with depth within a single reservoir column has been reported for many heavy oil and oil sand reservoirs in the Western Canadian Sedimentary Basin and elsewhere in the world. This study investigates, through reservoir simulation, the effects of viscosity variation with depth on the SAGD process and the resulting produced oil characteristics. Oil characteristics, including chemical component and viscosity profiles were built into a variety of reservoir simulation models. The simulation results indicate that the produced oil viscosity and component concentration vary as the steam chamber develops. The trend of the produced oil characteristics is related to the original in-situ profiles of and the reservoir flow barriers. In conjunction with oil rate, surface heave, or other available data, the produced oil characteristics may be used to suggest steam chamber development and the presence of barriers or baffles. The presented approach has potential to become a useful technique for SAGD steam chamber growth monitoring and production optimization.