Different inlet structures have a significant impact on the internal flow characteristics of a solid-magnesium powder water ramjet engine. Based on the magnesium-water reaction model, a computational fluid dynamics (CFD) method is applied to establish a numerical simulation method for the internal flow field of the engine, and the internal flow characteristics of the engine under different inlet structure conditions are studied. The simulation results show that high-temperature gas can effectively promote the ignition of magnesium powder at the top of the combustion chamber, while accelerating the evaporation of the first inlet water and increasing the combustion rate of magnesium powder. The secondary inlet has the most significant effect on the temperature inside the combustion chamber. When the secondary inlet flow rate increases towards the top of the combustion chamber, it increases the amount of heat absorbed by the evaporating water at the top of the chamber, thereby reducing the temperature at the top of the combustion chamber. However, when the flow rate is low, it results in insufficient oxidizer at the top of the combustion chamber, which is unfavorable for the combustion of magnesium powder.

Background Coronary artery disease (CAD) is a widely recognized cardiovascular disease that is considered the leading cause of death worldwide, affecting people on a global scale. Percutaneous coronary intervention (PCI), which involves procedures such as balloon angioplasty or stenting, plays an important role in opening blocked arteries and minimizing damage to the cardiac muscle. While the use of drug-eluting stents (DESs) has significantly reduced the occurrence of coronary restenosis, the problem of in-stent restenosis (ISR) continues to pose a significant clinical challenge. Gaining a deeper understanding of the clinical predictors associated with ISR is vital for early detection and appropriate treatment. Hence, this study aimed to evaluate the clinical predictors of ISR specifically in Taiwanese patients. Methods We conducted a single-center, retrospective case-control study, enrolling 517 CAD patients undergoing previous coronary stenting and stable angina with positive stress test or acute coronary syndrome (ACS) during follow-up between January 2019 and December 2022 at National Taiwan University Hospital. The patients were categorized into two groups: the ISR group, consisting of individuals who received drug-coated balloon (DCB) treatment (n=177), and the non-ISR group, comprising patients who did not receive DCB treatment (n=340). To gather relevant data, we meticulously reviewed the medical records and analyzed the findings from coronary angiography to assess the clinical characteristics of the patients. Results Patients with three-vessel disease (3VD) exhibited a higher prevalence of underlying diseases and were more likely to be taking aspirin and clopidogrel. Moreover, our analysis revealed that age (adjusted odds ratio [aOR] 1.02, 95% confidence interval [CI] 1.00 - 1.04, p = 0.037) and the presence of 3VD (adjusted odds ratio [aOR] 2.15, 95% confidence interval [CI] 1.03 - 4.46, p = 0.039) were significantly associated with an increased risk of coronary ISR. Conclusions Older age and 3VD were the independent predictors of coronary ISR in CAD patients receiving coronary stent implantation.

Dye/salt separation has gained increasing attention in recent years, prompting the quest for cost-effective and environmentally-friendly raw materials for synthesis high performance nanofiltration (NF) membrane for effective dye/salt separation. Herein, a high-performance loose structured NF membrane was fabricated by via a simple vacuum filtration method using a green nanomaterial, 2,2,6,6-tetramethylpiperidine-1-oxide radical (TEMPO)-oxidized cellulose nanofiber (TOCNF), by sequentially filtrating larger-size and finer-size TOCNFs on a microporous substrate, followed by cross-linked with trimesoyl chloride. The resultant TCM membrane possesses a separating layer composed entirely of pure TOCNF, eliminating the need for other polymer or nanomaterials additives. TCM membranes exhibits high performance and effective dye/salt selectivity. Scanning Electron Microscope (SEM) analysis shows that the TCM membrane with Fine-TOCNF layer has a tight layered structure. Further characterizations via Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) confirm the presence of functional groups and chemical bonds of the crosslinked membrane. Notably, the optimized TCM-5 membrane exhibits a rejection rate of over 99% for various dyes (Congo red, orange yellow) and 14.2% for NaCl, showcasing a potential candidate for efficient dye wastewater treatment.