An interval chance-constrained programming-based optimization model for carbon capture, utilization, and storage system planning.

Carbon capture, utilization, and storage (CCUS) are widely regarded as a crucial technological option for industrial large-scale carbon dioxide (CO2) emissions reduction. However, high-cost and uncertainties hinder the widespread application of CCUS technology. In this study, an interval-chance-constrained programming-based optimization model was proposed to address random probability distributions, interval values, complex interactions, and the dynamics of capacity expansion issues. The model was applied to a CCUS project in China. A set of violation probability levels (0.01, 0.05, 0.1, and 0.2) were designed to reflect system costs and risk levels. And then the solutions for system costs, capacity expansion, and operating schemes under four violation probability levels (pi') could be generated. The results revealed that the model could ensure the highest reliability and largest CO2 storage under pi' = 0.01. At this probability level, the amount of CO2 storage would range from 4972.05-5429.75 kilotons per annum (ktpa), the CCUS system cost would be highest at $166.57 million, and the net system benefits would be slightly less at $105.91 million. If policymakers strive to achieve the net system benefits of the project, the highest net system benefits would be achieved under pi' = 0.05. At this probability level, the net system benefits would increase to $135.45 million, the system cost would reduce to $138.62 million, but the total amount of CO2 storage would decrease to between 4090.01 and 4653.24 ktpa, which would entail a high risk of system violation. These findings enable policymakers to determine the trade-offs among system reliability, CO2 reduction, and the benefits of the project. The modeling approach can also address interactions among CCUS activities and the dynamics of facility expansion issues as well as help policymakers develop adaptive operational strategies. This study enriches CCUS research through an interval chance-constrained optimization modeling approach for CCUS system management under multiple uncertainties.

Fourier transform infrared spectroscopy research on subchondral bone in osteoarthritis.

Osteoarthritis (OA) is not only related to the degradation of articular cartilage, but also possibly to the changes of subchondral bone. The purpose of this study was to assess whether specific differences could be resolved from bone composition, as also contributed to OA. These differences were assessed by using Fourier transform infrared spectroscopy (FTIRS). The main parameters including mineral content, carbonate content, crystallinity, collagen cross-linking ratio (XLR) and acid phosphate content were represented with characteristic peak integration. It was found that mineral and carbonate content varied significantly with depths at different OA stages. Mineral content increased with depth in healthy samples, while carbonate content showed opposite trend. The mineral content reduced obviously with OA duration, which was different with carbonate decreasing only at early stage of OA. In addition, the content of acid phosphate, collagen maturity (XLR) and crystallinity slight varied with the OA aggravation. Therefore, the changes in subchondral bone were significantly associated with cartilage degeneration and OA, the associated parameters should be targeted for OA therapies.

Polarized infrared spectroscopy imaging applied to structural analysis of bilirubin aggregate at liquid-liquid interface.

Fourier transform infrared spectroscopy imaging (FTIRSI) combined with spectral analysis and polarization approach was creatively used to investigate both structures of bilirubin (BR) precipitate and BR aggregate at liquid-liquid interface. It was found by spectral analysis that the internal hydrogen bonds of BR molecules all broke and the dihedral angles increased during the formation of BR aggregate at liquid-liquid interface. And the BR molecule might be of layer assembly along the long axis direction of CD half-group to form J-type aggregates, which could be parallel to the direction of the transition dipole moment of BR aggregate. The further study of polarized imaging/anisotropy revealed that the absorbance of 1570 and 1703 cm-1 bands of BR aggregate changed periodically at intervals of 90°, which were not shown in BR precipitate case, indicating that the CC of the corresponding lactam ring and the CO of the adjacent carboxyl groups formed ordered arrangement in BR aggregate. It also suggested that the two positions might be the active sites which J-type aggregates assembled on. The combined technique was firstly applied in interfacial aggregate research, which was helpful for further understanding and controlling the aggregation as well as structural transformation of BR molecules so as to decrease physiological hazard and facilitate the wide spread application in biomedicine.