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• Integrated optimization model for biomass-based renewable hydrogen production systems is proposed. • We calculate and evaluate the biomass utilization potential of a certain area. • We made predictions through chemical reaction kinetics and thermodynamic models. • Inventory model is embedded in it to decide the optimal production and operation management. • The effectiveness of the model was tested through a mixed biomass project in Sichuan Province, China. In this study, we propose a novel optimization method for designing and operating various types of biomass-based renewable hydrogen production systems. To this end, we considered the coupling of multiple biomass hybrid utilization processes for hydrogen production. First, we calculated and evaluated the biomass utilization potential of a given area. Second, we predicted the biomass gasification products using chemical reaction kinetics and thermodynamic models. Finally, we determined the optimal annual total cost of the hydrogen production supply chain by optimizing the microscopic operation of the biomass gasification plant. Through the proposed method, it is possible to effectively conduct a comprehensive assessment of regional biomass material hydrogen production; moreover, the optimal design of the biomass hydrogen production supply chain can also be determined based on the availability of biomass and hydrogen demand. More precisely, the logistics operations under fluctuating demand conditions were realized, enabling strategic decision-making for planning a biomass hydrogen production system. To validate the model, a case study analysis of biomass hydrogen production, to be launched in Sichuan Province, China, is presented. [ABSTRACT FROM AUTHOR]

No shale-rock physical model has been established in the observation coordinate system. To this end, this paper carried out anisotropic wave velocity tests on shale rock and compared the Thomsen, Daley, and Berryman solutions to characterize anisotropic acoustic wave velocity. Finally, the Daley solution was selected. Based on basic rock physical models, such as SCA and DEM methods, and combined with the Daley solution, an anisotropic shalerock physical model was established in the observation coordinate system and applied in Well B1 in the Luzhou area, Sichuan Basin. Our research conclusions were as follows: 1. for the samples from the same core, the P-wave velocities in three directions were in the order VP11 >VP45 >VP33, shear-wave velocity VS11 was the largest, but VS33 and VS45 did not follow the law of Vs33 >Vs45 for some samples; 2. the Daley solution, which not only considers the accuracy requirements but also has a complete expression of P-, SV-, and SH-waves, is most suitable for characterization of anisotropic wave velocity in this study area; 3. the rock physical model constructed in the observation coordinate system has high accuracy, in which the absolute value of the relative error of the P-wave slowness was between 0% and 5.05% (0.55% on average), and that of shear-wave slowness was between 0% and 6.05% (0.59% on average); 4. the acoustic waves recorded in Well B1 in the observation coordinate system were very different from those in the constitutive coordinate system. The relative difference of the P-wave was between 6.76% and 30.84% (14.68% on average), and that of the S-wave was between 7.00% and 23.44% (13.99% on average). The acoustic slowness measured in the observation coordinate system, such as in a deviated well or a horizontal well section, must be converted to the constitutive coordinate system before it can be used in subsequent engineering applications; 5. the anisotropic shale-rock physical model built in the observation coordinate system proposed in this paper can provide basic data and guidance for subsequent pore pressure prediction, geomechanical modeling, and fracturing stimulation design for deviated and horizontal wells. [ABSTRACT FROM AUTHOR]

Background and purpose: The aim was to investigate the neurological complications associated with coronavirus disease 19 (COVID‐19) during the 2022 Omicron wave. Methods and analysis: The medical records of a cohort of people admitted to neurological wards of three participating tertiary centres in Sichuan from 12 December 2022 to 12 January 2023 were reviewed. Demographics and clinical data were obtained and analysed with an interest in COVID‐19‐related new‐onset or worse neurological symptoms. The current data were also compared in two centres with similar data from the same period 12 months earlier. Results: In all, 790 people were enrolled, of whom 436 were positive for COVID‐19. Ninety‐nine had new onset COVID‐related neurological problems, or their known neurological condition deteriorated during the wave. There was a significant difference in demographics from the findings amongst admissions 12 months earlier as there was an increase in the average age, the incidence of encephalitis and encephalopathy, and mortality rates. One hundred and one received COVID‐specific antivirals, intravenous glucocorticoids and intravenous immunoglobulin therapy. No differences were seen between these and those who did not use them. Conclusion: New‐onset neurological conditions, particularly encephalitis and encephalopathy, increased significantly during this period. Deterioration of existing neurological conditions, such as seizure exacerbation, was also observed. A large‐scale treatment trial of people with COVID‐19 infection presenting with neurological disorders is still needed. [ABSTRACT FROM AUTHOR]