Pneumatically agitated slurry reactors, including bubble column reactors and airlift loop reactors (ALRs), are important gas–liquid–solid multiphase reactors. These reactors have been widely applied in many processes, especially in the biological fermentation and energy chemical industry, due to their low shear stress, good mixing, perfect mass-/heat-transfer properties, and relatively low costs. To further improve the performance of slurry reactors (i.e., mixing and mass/heat transfer) and to satisfy industrial requirements (e.g., temperature control, reduction of back-mixing, and product separation), the process intensification of slurry reactors is essential. This article starts by reviewing the latest advancements in the intensification of mixing and mass/heat transfer in these two types of reactors. It then summarizes process-intensification methods for mixing and separation that allow continuous production in these slurry reactors. Process-intensification technology that integrates directional flow in an ALR with simple solid–liquid separation in a hydrocyclone is recommended for its high efficiency and low costs. This article also systematically addresses vital considerations and challenges, including flow regime discrimination, gas spargers, solid particle effects, and other concerns in slurry reactors. It introduces the progress of numerical simulation using computational fluid dynamics (CFD) for the rational design of slurry reactors and discusses difficulties in modeling. Finally, it presents conclusions and perspectives on the design of industrial slurry reactors.
Polypropylene (PP) scaffolds are the most commonly used biomedical scaffolds despite their disadvantages, which include problems with adhesion, infection, and inflammatory responses. Here, we report on the successful development of a facile one-step method to fabricate a series of novel triclosan polydopamine polypropylene (TPP) composite scaffolds and thereby effectively improve the biocompatibility and long-term antibacterial properties of PP scaffolds. The antibacterial triclosan can effectively interact with dopamine during biocompatible polydopamine formation on the PP scaffold by one-step green fabrication. Thanks to the sustained release of triclosan from the biocompatible polydopamine coating, a 5 mm × 5 mm sample of TPP-coated scaffold made with a triclosan concentration of 8 mg∙mL−1 (referred to herein as TPP-8) exhibited a continuous antibacterial effect against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) for more than 15 d, at maximum antibacterial volumes of 2 and 5 mL, respectively. Our study establishes a new direction for facile long-term antibacterial studies for medical applications.
Concentrated solar power (CSP) plants with thermal energy storage (TES) system are emerging as one kind of the most promising power plants in the future renewable energy system, since they can supply dispatchable and low-cost electricity with abundant but intermittent solar energy. In order to significantly reduce the levelized cost of electricity (LCOE) of the present commercial CSP plants, the next generation CSP technology with higher process temperature and energy efficiency is being developed. The TES system in the next generation CSP plants works with new TES materials at higher temperatures (> 565 °C) compared to that with the commercial nitrate salt mixtures. This paper reviews recent progress in research and development of the next generation CSP and TES technology. Emphasis is given on the advanced TES technology based on molten chloride salt mixtures such as MgCl2/NaCl/KCl which has similar thermo-physical properties as the commercial nitrate salt mixtures, higher thermal stability (> 800 °C), and lower costs (< 0.35 USD∙kg−1). Recent progress in the selection/optimization of chloride salts, determination of molten chloride salt properties, and corrosion control of construction materials (e.g., alloys) in molten chlorides is reviewed.
The complex compositions and large shrinkage of concrete, as well as the strong constraints of the structures, often lead to prominent shrinkage cracking problems in modern concrete structures. This paper first introduces a multi-field (hydro–thermo–hygro–constraint) coupling model with the hydration degree of cementitious materials as the basic state parameter to estimate the shrinkage cracking risk of hardening concrete under coupling effects. Second, three new key technologies are illustrated: temperature rise inhibition, full-stage shrinkage compensation, and shrinkage reduction technologies. These technologies can efficiently reduce the thermal, autogenous, and drying shrinkages of concrete. Thereafter, a design process based on the theoretical model and key technologies is proposed to control the cracking risk index below the threshold value. Finally, two engineering application examples are provided that demonstrate that concrete shrinkage cracking can be significantly mitigated by adopting the proposed methods and technologies.
A new generation of fluid pressure forming technology has been developed for the three typical structures of tubes, sheets, and shells, and hard-to-deform material components that are urgently needed for aerospace, aircraft, automobile, and high-speed train industries. In this paper, an overall review is introduced on the state of the art in fundamentals and processes for lower-pressure hydroforming of tubular components, double-sided pressure hydroforming of sheet components, die-less hydroforming of ellipsoidal shells, and dual hardening hot medium forming of hard-to-deform materials. Particular attention is paid to deformation behavior, stress state adjustment, defect prevention, and typical applications. In addition, future development directions of fluid pressure forming technology are discussed, including hyper lower-loading forming for ultra-large non-uniform components, precision forming for intermetallic compound and high-entropy alloy components, intelligent process and equipment, and precise finite element simulation of inhomogeneous and strong anisotropic thin shells.
The clinical application of lung ultrasound (LUS) in the assessment of coronavirus disease 2019 (COVID- 19) pneumonia severity remains limited. Herein, we investigated the role of LUS imaging in COVID-19 pneumonia patients and the relationship between LUS findings and disease severity. This was a retrospective, observational study at Tongji Hospital, on 48 recruited patients with COVID-19 pneumonia, including 32 non-critically ill patients and 16 critically ill patients. LUS was performed and the respiratory rate oxygenation (ROX) index, disease severity, and confusion, urea nitrogen, respiratory rate, blood pressure and age (CURB-65) score were recorded on days 0–7, 8–14, and 15–21 after symptom onset. Lung images were divided into 12 regions, and the LUS score (0–36 points) was calculated. Chest computed tomography (CT) scores (0–20 points) were also recorded on days 0–7. Correlations between the LUS score, ROX index, and CURB-65 scores were examined. LUS detected COVID-19 pneumonia in 38 patients. LUS signs included B lines (34/38, 89.5%), consolidations (6/38, 15.8%), and pleural effusions (2/38, 5.3%). Most cases showed more than one lesion (32/38, 84.2%) and involved both lungs (28/38, 73.7%). Compared with non-critically ill patients, the LUS scores of critically ill patients were higher (12 (10–18) vs 2 (0–5), p < 0.001). The LUS score showed significant negative correlations with the ROX index on days 0–7 (r = −0.85, p < 0.001), days 8–14 (r = −0.71, p < 0.001), and days 15–21 (r = −0.76, p < 0.001) after symptom onset. However, the LUS score was positively correlated with the CT score (r = 0.82, p < 0.001). The number of patients with LUS-detected lesions decreased from 27 cases (81.8%) to 20 cases (46.5%), and the LUS scores significantly decreased from 4 (2–10) to 0 (0–5) (p < 0.001) from days 0–7 to 17–21. We conclude that LUS can detect lung lesions in COVID-19 pneumonia patients in a portable, real-time, and safe manner. Thus, LUS is helpful in assessing COVID-19 pneumonia severity in critically ill patients.
Irritable bowel syndrome with diarrhea (IBS-D) is chronic intestinal dysfunction with diarrhea and other complicated clinical symptoms, and it has a great impact on the daily life and mental state of patients. Some studies have reported that ingestion of probiotics can significantly alleviate a variety of intestinal diseases. The purpose of this study was to investigate the IBS-D-alleviating effects of a probiotic strain, Lactobacillus plantarum CCFM8610, with multiple health-promoting effects. The study was a 12-week, randomized, double-blind, placebo-controlled, pilot clinical trial. Seventy-five patients were randomly assigned to receive the placebo, oligosaccharides, or L. plantarum CCFM8610 (1 × 1010 colony-forming units (CFU) per day), with a 2-week run-in period, an 8-week intervention period, and a 2-week follow-up observation period. The patients' clinical symptoms and quality of life were examined by the IBS symptom severity scale (IBS-SSS) and the IBS quality of life scale (IBS-QOL). Changes in gut microbiota composition and diversity were measured at the end of the intervention period. The oral administration of L. plantarum CCFM8610 significantly decreased the IBS-SSS and IBS-QOL scores, reduced IBS-D symptom severity, recovered gut microbiota diversity, decreased the relative abundance of bloating-related genus Methanobrevibacter, and increased the relative abundance of butyric acid-producing genera, including Anaerostipes, Anaerotruncus, Bifidobacterium, Butyricimonas, and Odoribacter. These findings suggest that ingestion of L. plantarum CCFM8610 can significantly alleviate clinical symptoms and gut microbiota dysbiosis in IBS-D patients. The IBS-D-alleviating effect of L. plantarum CCFM8610 may be related to the increase in the relative abundance of butyric acid-producing genera in the intestine.
At present, most total knee replacement (TKR) prostheses on the market are designed according to the sizes of Caucasians. However, extensive studies have indicated that human anatomies differ among different ethnicities. A number of reports have indicated that Chinese TKR patients do not match with available prostheses. In this study, computed tomography (CT) images of 52 knees of Chinese men and women were used for anthropometric measurements. Index and geometric measurements were defined and used for correlation analysis. Key parameters from the measurement results were identified. Detailed geometries of knees were measured as coordinates. A deformable three-dimensional (3D) knee model based on anatomical coordinates correlating with the identified key parameters was generated. A prosthesis was then designed according to the analyzed results. Surface matching analysis, bone resection analysis, and cadaveric trials were conducted and compared with commercial products to validate the proposed design. The femoral component designed by this study resulted in the highest accuracy (root mean square point-to-surface (RMS PS), (1.08 ± 0.20) mm) and lowest amount of resected bone volume (27 412 mm3) in comparison with two commercial knee prostheses. This study suggests a new approach for population-based patient-specific femoral prosthesis design. With a single, easily acquired dimension—namely, epicondyle width (ECW)—as input, a patient-specific femoral prosthesis can be designed according to the analyzed measured data and manufactured by additive manufacturing (AM) methods. Meanwhile, the reconstructed femoral condylar surface was compared with the femoral condylar surface in the original CT scanning data. The average RMS PS distance of the reconstructed femoral condylar surface among all data was (1.10 ± 0.18) mm, which is comparable to other statistical shape modeling methods using multiple radiographs as input data. There is a need to develop an anthropometric-based knee prosthesis for the Chinese population. Based on the anthropometry of the Chinese population, our new design fits Chinese patients better and reserves more bone volume compared with current commercial prostheses, which is an essential step toward AM for personalized knee prostheses.
External short circuit (ESC) of lithium-ion batteries is one of the common and severe electrical failures in electric vehicles. In this study, a novel thermal model is developed to capture the temperature behavior of batteries under ESC conditions. Experiments were systematically performed under different battery initial state of charge and ambient temperatures. Based on the experimental results, we employed an extreme learning machine (ELM)-based thermal (ELMT) model to depict battery temperature behavior under ESC, where a lumped-state thermal model was used to replace the activation function of conventional ELMs. To demonstrate the effectiveness of the proposed model, we compared the ELMT model with a multi-lumped-state thermal (MLT) model parameterized by the genetic algorithm using the experimental data from various sets of battery cells. It is shown that the ELMT model can achieve higher computational efficiency than the MLT model and better fitting and prediction accuracy, where the average root mean squared error (RMSE) of the fitting is 0.65 °C for the ELMT model and 3.95 °C for the MLT model, and the RMES of the prediction under new data set is 3.97 °C for the ELMT model and 6.11 °C for the MLT model.
Single nucleotide polymorphism (SNP) arrays are a powerful genotyping tool used in genetic research and genomic breeding programs. Japanese flounder (Paralichthys olivaceus) is an economically-important aquaculture flatfish in many countries. However, the lack of high-efficient genotyping tools has impeded the genomic breeding programs for Japanese flounder. We developed a 50K Japanese flounder SNP array, ″Yuxin No. 1,″ and report its utility in genomic selection (GS) for disease resistance to bacterial pathogens. We screened more than 42.2 million SNPs from the whole-genome resequencing data of 1099 individuals and selected 48 697 SNPs that were evenly distributed across the genome to anchor the array with Affymetrix Axiom genotyping technology. Evaluation of the array performance with 168 fish showed that 74.7% of the loci were successfully genotyped with high call rates (> 98%) and that the polymorphic SNPs had good cluster separations. More than 85% of the SNPs were concordant with SNPs obtained from the whole-genome resequencing data. To validate ″Yuxin No. 1″ for GS, the arrayed genotyping data of 27 individuals from a candidate population and 931 individuals from a reference population were used to calculate the genomic estimated breeding values (GEBVs) for disease resistance to Edwardsiella tarda. There was a 21.2% relative increase in the accuracy of GEBV using the weighted genomic best linear unbiased prediction (wGBLUP), compared to traditional pedigree-based best linear unbiased prediction (ABLUP), suggesting good performance of the ″Yuxin No. 1″ SNP array for GS. In summary, we developed the ″Yuxin No. 1″ 50K SNP array, which provides a useful platform for high-quality genotyping that may be beneficial to the genomic selective breeding of Japanese flounder.