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Quantification of visible ambient plume opacity measurements using compact and smartphone digital still cameras (DSCs), and Digital Optical Method (DOM) are evaluated here. A new camera calibration method that employs exposure value compensation in place of exposure time or radiance of a surface is described and evaluated. This new and simpler method allows an automatic exposure controlled DSC to be calibrated using its own DSC settings. We also test the use of color in place of grayscale pixel values (PVs) to measure opacity. Finally, we determine the uncertainty of the opacity measurements. Two compact DSCs and two smartphone DSCs are tested to measure plume opacity values of smoke generated with an outdoor smoke generator, in comparison to the plume opacity values measured with an in-stack transmissometer. Results show that: 1) smartphone DSCs, like compact DSCs, can pass opacity measurement requirements set by USEPA; 2) the new simpler calibration method generates values within 5% in opacity on average compared to opacity values from the reference transmissometer; 3) non-uniform background color dominates the uncertainty of opacity measurements, and such uncertainty is wavelength dependent; and 4) the diffusive scattering parameter, used in DOM's transmission model, is lower for black plumes than white plumes, and is wavelength dependent. These results improve our understanding of using DSCs and the parameters that introduce uncertainty to DOM to improve measurements of plume opacity that can improve protection of human health.

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Carbon Capture, Utilization and Storage (CCUS) is one of the key technologies for realizing large-scale low-carbon utilization of coal-fired power plants in service. How to evaluate its economics is crucial to the decision-making of traditional coal-fired power enterprises. This paper analyzes the changes in the physical, emission and economic parameters of in-service coal-fired power plants without and with the CCUS retrofit. A method for evaluating the economic feasibility of coal-fired power plants retrofitting based on net cash flow is proposed, which compares the impact of CCUS retrofit on the net present value of the remaining life cycle of the power plant. The impact of uncertain parameters such as carbon dioxide sales unit price, carbon capture device operating cost, free carbon quota, and carbon emission right price on the evaluation results are analyzed.

Background: The human-like collagen I (HLC-I) combined concentrated growth factors was used to construct CGF-HLC-I composite biomaterials to repair the critical bone defect disease model of rabbit mandible. This study aimed to research the repair mechanism of CGF-HLC-I/Bio-Oss in rabbit mandibular critical bone defect, to provide a new treatment direction for clinical bone defect repair.Methods: The optimal concentration of HLC-I (0.75%) was selected in this study. Nine New Zealand white rabbits were randomly divided into 3 groups, normal control group, Bio-Gide/Bio-Oss and CGF-0.75%HLC-I/Bio-Oss group (n = 3, each group). CGF-0.75%HLC-I/Bio-Oss and Bio-Gide/Bio-Oss were implanted into rabbit mandibles, then X-ray, Micro-CT, HE and Masson staining, immunohistochemical staining and biomechanical testing were performed with the bone continuity or maturity at 4, 8 and 12 weeks after surgery. The repair mechanism was studied by bioinformatics experiments.Results: As the material degraded, the rate of new bone formation in the CGF-0.75% HLC-I/Bio-Oss group was better than that the control group by micro-CT. The biomechanical test showed that the compressive strength and elastic modulus of the CGF-0.75%HLC-I/Bio-Oss group were higher than those of the control group. HE and Masson staining showed that the bone continuity or maturity of the CGF-0.75%HLC-I/Bio-Oss group was better than that of the control group. Immunohistochemical staining showed significantly higher bone morphogenetic protein 2 (BMP2) and Runt-related transcription factor 2 (RUNX2) in the CGF-0.75%HLC-I/Bio-Oss group than the control group at 8 and 12 W and the difference gradually decreased with time. There were 131 differentially expressed proteins (DEPs) in the Bio-Gide/Bio-Oss and CGF-0.75%HLC-I/Bio-Oss groups, containing 95 up-regulated proteins and 36 down-regulated proteins. KEGG database enrichment analysis showed actinin alpha 1 (ACTN1) and myosin heavy-Chain 9 (MYH9) are the main potential differential proteins related to osteogenesis, and they are enriched in the TJs pathway.Conclusion: CGF-0.75%HLC-I/Bio-Oss materials are good biomaterials for bone regeneration which have strong osteoinductive activity. CGF-0.75%HLC-I/Bio-Oss materials can promote new bone formation, providing new ideas for the application of bone tissue engineering scaffold materials in oral clinics.