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Plastic pollution is a global problem and many countries are strengthening their regulations to mitigate the related environmental degradation and health risks and to support the development and deployment of circular economy for various types of plastics. As Canada also develops its strategy for regulating single-use plastic as one element of the plastic pollution, aligned federal and provincial policies are essential. This study presents an analysis of existing and emerging policies to provide guidance on Canada's future regulations. Qualitative and quantitative data regarding plastic regulations were gathered from similar countries including Australia, the United Kingdom, the European Union, the United States and relevant scientific articles. Analysis was also conducted of current Canadian regulations that both impact and guide the path for plastic regulation, international examples provided guidance for future Canadian regulations. The analysis found that there is a need for public education on the gravity of plastic pollution to gain their support; for establishing pioneering provinces or cities in plastic regulations to learn from and provide other cities with support; and to start with banning items with available alternatives, to be followed by phasing out other items that are more difficult to replace. The study also showed potential areas of improvement in impact data. The need for reliable regulatory performance data against a baseline scenario; consistency in methodology; and proper scoping to reduce the risk of displacement or exclusivity in policy were identified. [ABSTRACT FROM AUTHOR]

Considering that in the previous work of the group, the physical, electrochemical and catalytic properties of Bi–V–O samples without doping were studied, in this research work we decided to investigate the said properties for samples doped with different ions to compare data and results. Hydrothermal fabrication of some Mx-doped Bi–V–O (M = doped metal) mixed metal oxides was reported in the present study. Several standard techniques, such as energy dispersive X-ray, field emission scanning electron microscopy (FESEM), X-ray powder diffraction, transmission electron microscopy (TEM), ultraviolet–visible (UV–Vis), cyclic voltametry (CV), and vibrating sample magnetometer (VSM), were employed to specify the virtues of the prepared samples. XRD data confirmed that Bi2V2O7 and BiVO4 were the main crystal phases in the mixture of the products. FESEM and TEM images showed that the samples had particle and rod morphologies. The presence of strong spectra in the range of visible light were confirmed using the UV–Vis spectroscopy. The prepared composites' direct band gap energy (Eg) values were among 2 and 5 eV. According to VSM analysis, the results revealed that the samples showed weak magnetic behavior. The highest magnetic property was considered with the intercalating of Fe into the crystal system. Electrochemical properties measured by CV analysis showed that the samples had considerable charge discharge-specific capacitance values. Besides, the samples showed weak oxidation–reduction peaks indicating the possible battery and, or electrocatalyst application. The catalytic performance of the substance was studied for the synthesis of chromene derivatives. A high yield was obtained when ultrasound irradiation was used. In the following, we intend to study the photocatalytic and antibacterial activity of the synthesized samples (pure and doped samples) and compare the results with the components which used in the nanocomposite structure. [ABSTRACT FROM AUTHOR]

Solid state synthesis of some new Mx-CuSb2O6-CuSb2O4 (Mx=None, Fe, Ni, Ce and Yb) nanocomposites was introduced in the present research study. The physicoelectrochemical properties of synthesized nanocomposites were investigated by different techniques, such as XRPDT, Rietveld, FTIR, FESEM, UV-Vis, VSM, CV and EIS. Rietveld analysis data revealed that all of the synthesized samples display the monoclinic crystal phase with the space group of P21/n. The estimated direct band gap energy of the obtained nanocomposites was in the range of 2.0 to 2.7 eV, which confirms that are active in ultraviolet-visible region. The VSM data indicated that the maximum magnetic behavior was found for Ni doped — Cu−Sb−O nanocomposite. Also, the catalytic performance of nanocomposites to synthesis 2-amino-4H-benzochromenes under ultrasonic and microwave was investigated. The considered parameters, such as solvent type, catalyst amount and reaction time, influencing the yield of the 4H-benzochromene reaction were studied. The maximum yield for the synthesizing of the 4H-benzochromene compounds was obtained when EtOH was used as the reaction solvent. The catalyst amount and reaction time were 15 mol% and 8 min, respectively, under ultrasonic conditions, while benzaldehyde was used as an aldehyde derivative. [ABSTRACT FROM AUTHOR]

Mx‐MoO3‐α‐NaFe2(MoO4)3‐α‐FeMoO4 (M = Al, Co, Ni, and Er) nanomaterials were fabricated by the hydrothermal method in the present study. XRPD, FESEM, TEM, BET‐BJH, UV‐Vis, and VSM analyses were used to characterize and study the physical attributes of the as‐synthesized samples. Rietveld analysis data illustrated that the products were a mixture of α‐NaFe2(MoO4)3, α‐FeMoO4, MoO3, and Fe2O3 crystal phases. UV‐Vis spectra indicated that the obtained samples had a small direct band gap energy amount at about 1.3–1.5 eV. VSM analysis confirmed that the as‐fabricated samples had magnetic properties. However, most ferromagnetic behaviors were observed by doping Ni into the host crystal system. Catalytic synthesis of some 5‐aryl‐1H‐tetrazole analogs was performed under heat, microwave, and ultrasonic conditions. Reaction time, temperature, and solvent type parameters were studied to find the optimum conditions. High efficiency was obtained when ethyl alcohol was used as the reaction mixture solvent. [ABSTRACT FROM AUTHOR]

Introduction Nowadays, granitoide masses are of interest due to their high strength, low porosity and various applications. The rock masses are considered as places for radioactive waste and toxic materials disposal, carbon dioxide storage, thermal drilling and enhanced geothermal systems. Extreme temperature changes are common in such cases and can have destructive effects on the primary structure of the rock. Induced microcracks (Tian et al., 2012) and opening passageways for the entry of fluids are some effects of thermal changes and shock, which result in increment of the granitoide mass permeability and creation of suitable places to fracture due to tectonic stresses (Dwivedi et al., 2008; Rathnaweera et al., 2018; Kang and Li, 2021). The rocks in nature inherently have characteristics that are measured in laboratory tests as physical characteristics. These properties such as density, porosity, texture and particle size are effective on the mechanical behaviour of rock, and some of them change with temperature change (Benson et al., 2007; Yang et al., 2017). The variation of mechanical properties affected by temperature are related to factors such as primary pore structure, particle size, mineral composition, mineral texture, and water content (Mo et al., 2022). The thermal properties of rocks are mainly measured by two indices of thermal conductivity and thermal expansion, although thermal conductivity is related to thermal diffusivity, specific heat and density (Siegesmund and Snethlage, 2011). Among the rocks, quartz-rich rocks exhibit a higher average thermal conductivity, whereas rocks with increasing feldspar contents show decrement in thermal conductivity values (Siegesmund and Snethlage, 2011; Ray et al., 2021). Thermal conductivity decreases with increasing temperature. (Görgülü et al., 2008; Fuchs and Förster, 2010; Qin et al., 2020; Ye et al., 2022). Thermal conductivity increases with increasing pressure, especially in the low pressure range, which was attributed to the closure of microcracks and voids (Siegesmund and Snethlage, 2011). In oriented rocks and minerals heat transfer and diffusion depends on the direction of minerals and layering in rocks. Mica minerals especially muscovite, have good thermal conductivity parallel to layering. Phyllosilicate minerals like illite, muscovite and chlorite also play a similar role. But quartz itself exhibits an 42% anisotropy in two perpendicular directions (Siegesmund and Snethlage, 2011). In thermal shock, heating and cooling have different effect on the rock volumetric expansion and anisotropy of thermal expansion as well as residual expansion causes permanent lengt h change which is related to the formation of thermal cracks (Den'gina et al., 1993). The coefficient of thermal expansion determines the material's response to heat or cold. The residual strain after exposure to a heat determines the thermal sensitivity of the rock. In a rock that consists of different minerals, the interaction of all the mentioned factors leads to microcracks and thermally induced cracks in the rocks. Thermal cracking, in coarse-grained, quartz-rich rocks is dominant during heating (expantion) while in fine-grained, quartz-poor rock, is dominant during cooling (contraction) (Browning et al, 2016; Meredith et al, 2019; Browning et al, 2021). Rocks such as granit, neurite and quartzite under the condition of the earth crust with temperatures up to 900 c and higher pressures undergo thermal cracks (Ide, 1937; Richter and Simmons, 1974; Simmons and Cooper, 1978; Bauer and Johnson, 1979; Glover et al., 1995; Lu and Jackson, 1998; Liu et al., 2021; Feng et al., 2021; Guo et al., 2021). For research about the effect of heat on granitoids, three different fresh granitoid samples have been examined in terms of physical, mineralogical characteristics and the development of microcracks. They were subjected to 4 different temperature shocks and the thermal shock effects on development of microcracks was described by using PPL and XPL photos of the samples' thin section. This study has depicted the behaviour of minerals and various textures of granitoids after different shocks also has shown the destructive effects of thermal shock on the initial structure of them. Study of thermal shock effects that lead to development of microcracks and passages could be useful in evaluating how to increase permeability the granitoid masses. Materials and Methods For this study 3 granitoids samples were prepared from 3 different mass located in the structural zone of Sanandaj-Sirjan which were subjected to different tests before and after thermal shock. Samples were taken from Hasan rebat mass at Golpaygan area, Alvand Mass at Hamedan area and Marivan mass at northern area of Marivan. Samples were prepared as follows: blocks were moved from mass place to the laboratory. They were cored and then cut into 3 cm height. Microscopic thin sections were prepared from fresh samples in 3 perpendicular directions. In order to induce thermal microcrack, the samples were heated in a high temperature furnace up to the desired temperature at a rate of 5 (Cᵒ/min) and kept at intended temperature for 2 hours to ensure entire samples volume were completely isothermal. Temperatures were 250, 450, 650, 850 Cᵒ. Then the samples were removed from the furnace, they were immediately immersed in municipal water (20 to 25 Cᵒ). Immersion was continued until the samples were at the same temperature as water, because of this, water flow into the bucket has been continued. For preparing to three-dimensional sectioning, the shocked samples were dried in an oven (max 50 c). Three perpendicular directions including two diametric directions and one axial direction, were determined on the cores from the first sampling to the last stage of each test. Two diametric directions were named "R plane" & "B plane" and the axial plane which was perpendicular to the axis the cores and was perpendicular to the two diametric directions, called "N plane". To determine lithological characteristics and liner crack density thin sections inspection of fresh and shocked samples were done in three directions. Physical properties were determined based on ISRM standard tests. The thermal shock effects on granitoids were explained by using SEM images, thin section images and images of macroscopic samples. Conclusion This research showed that it is possible to evaluate how the sample reacts to heat by microscopic examination of the thin section of fresh samples. In short, we can say: In the studied granitoids, medium grain size and uniform texture also various boundaries (smooth and jogged) could increase the resistance of the granitoid against the formation of microcracks. The presence of myrmekite texture makes granitoid susceptible to the formation of transgranular microcracks. Micas and quartz as inclusion inside coarse minerals could cause the formation of intragranular microcracks. In general, very few microcracks generate in plagioclase unlike the orthoclase which the most microcracks form inside it. Mostly intragranular microcracks form at cleavage and perthite texture site inside the orthoclase. smooth boundaries abundance and jagged boundaries abundance have a positive effect on the development of microcracks. In coarse-grained granitoide, increment of very fine or very coarse mineral abundance, cause accelerate the development of microcracks. According to the average grain size, it was expected that the Hasan Rabat sample be in an intermediate state compared to the other samples. Meanwhile the development rate of microcracks induced by thermal shock in the Alvand and Marivan sample are similar, their grain sizes are completely different. Hasan Rebat sample shows completely different behaviour in development rate of all kind of microcrack (intra-, transand intergranular). Results demonstrated that the absolute age of granitoide is an important factor in the rate and manner of microcrack development. [ABSTRACT FROM AUTHOR]

Objective: The function of Th17 cells in the neuroinflammatory process in multiple sclerosis (MS) has been previously clarified. It has been suggested that Quercetin can influence MS due to a variety of anti-inflammatory effects. The present study aimed to examine in vitro immunomodulatory aspects of Quercetin Penta Acetate as a modified compound on Th17 cells of MS patients and also to compare its effects with Quercetin. Materials and Methods: In this experimental study, peripheral blood mononuclear cell (PBMCs) were isolated and stained with CFSE then, half-maximal inhibitory concentration (IC50) values were determined using different doses and times for Quercetin Penta Acetate, and Methyl Prednisolone Acetate. Th17 cell proliferation was analyzed by flow cytometry and the expression levels of IL-17 and RORc genes were assessed by real-time polymerase chain reaction (PCR) method. Results: The results showed that IL-17A gene expression was inhibited by Quercetin Penta Acetate (P=0.0081), but Quercetin Penta Acetate did not have a significant inhibitory effect on Th17 cells proliferation (P= 0.59) and RORc gene expression (P=0.1), compared to Quercetin. Conclusion: Taken together, our results showed some immunomodulatory aspects of Quercetin Penta Acetate on Th17 cells are more effective than Quercetin and it could be considered in the treatment of MS. [ABSTRACT FROM AUTHOR]