Search

As a new type of energy-containing material, Ammonium dinitramide based liquid propellant has the advantages of being green, having low toxicity, good stability, and high safety performance. Traditional catalytic combustion methods require preheating of the catalytic bed and deactivation of the catalytic particles at high temperatures, while microwave ignition methods can effectively solve these problems. To study the combustion characteristics of ADN-based liquid propellants during microwave ignition, the influence of microwave power and gas flow rates on the combustion process are analyzed using experimental methods. A high-speed camera was used to observe the enhanced effects of microwave power and gas flow on plasma and flame. Combined with temperature measurement, the combustion process of ADN-based liquid propellants under the action of plasma was analyzed. The combustion process in the presence of microwaves was observed by comparing parameters such as flame length, flame temperature, and radical intensity. Those results show that, with the increase in microwave power, the luminous burning area of the flame grows significantly. The microwave power is increased by 250 W each, and the flame jet length is increased by nearly 20%. The increase in microwave power also leads to an increase in propellant combustion temperature, however, this increase gradually slows down. At a gas flow rate of 20 L/min, the ADN-based liquid propellant showed the best combustion performance with a maximum jet length of 14.51 cm and an average jet length increase of approximately 85.9% compared to 14 L/min. Too much gas flow rate will hinder the development of the jet, while the high-velocity airflow will have a cooling effect on the flame temperature. The results provide a basis for the specific parameter design of microwave ignition and promote the application of ADN-based liquid propellants in the aerospace field. [ABSTRACT FROM AUTHOR]

We consider a supply chain where a manufacturer directly sells products to end consumers through an online marketplace operated by an e‐tailer, where the e‐tailer is a leader and the manufacturer is a follower. Logistics service is a key influence factor to online marketplace. We present four service channels: (1) E‐channel, the e‐tailer offers the service; (2) E3P‐channel, the e‐tailer outsources the service to a 3PL; (3) M‐channel, the manufacture offers the service; and (4) M3P‐channel, the manufacture outsources the service to a 3PL. This study investigates the optimal decisions and profits for e‐tailer and manufacturer among different service channels, respectively, equilibrium choice of service channel and examines the consistency on choosing the service channel between them. We find that whether the market demand is a log‐separable function form or a linear function form, when the fraction of supply chain revenue sharing is large, E‐channel is the equilibrium choice, otherwise M‐channel is the equilibrium one. Further, we use the sharing fraction threshold gap between e‐tailer and manufacturer to describe the extent of the consistency on choosing the service channel. We find increasing demand sensitivity to service level or decreasing cost sensitivity to service level would enhance the consistency. Moreover, we extend to analysis with linear demand function and different service costs for firms. Finally, the e‐tailer or the manufacturer switches to outsource service to a 3PL when the service cost of the 3PL is not large. Specifically, the 3PL also benefits from the consistent service channel choice under certain condition. [ABSTRACT FROM AUTHOR]

Background: Spread through air spaces (STAS) is significantly associated with decreased overall survival (OS) and reduced recurrence-free survival. However, there are no reliable methods to confirm the presence of STAS before surgery. The sensitivity and specificity of the intraoperative frozen section diagnosis of STAS are not satisfactory. This study sought to determine the clinical, pathological, and computed tomography (CT) features of lung cancer with STAS before surgery to guide treatment decisions., Methods: The data of 121 patients who were positive for STAS and 121 who were negative for STAS as confirmed by surgery and pathology were collected at Jiangsu Cancer Hospital from January 2020 to December 2022. The differences between the two groups in terms of the clinical, pathological, and CT characteristics were compared., Results: STAS occurred not only in lung adenocarcinoma (LUAD) (106 of 121, 87.6%), but also in other pathological types of lung cancer (15 of 121, 12.4%). STAS was significantly correlated with pathological invasiveness [pathological differentiation, tumor, node, metastasis (TNM) staging, vascular invasion, and pleural invasion; all P<0.05]. STAS was most common in solid tumors (95 of 121, 78.51%). The receiver operating characteristic (ROC) curve showed that the optimal cut-off value for diagnosing STAS based on diameter is 1.55 cm with a sensitivity of 73.3% and a specificity of 47.9%. The percentage of solid components (PSC) is an independent influencing factor of lung cancer with STAS [odds ratio (OR) =111.27; P<0.05] with an optimal cut-off value of 63%, a sensitivity of 92.5%, and a specificity of 72.7%. In the part-solid nodules, the occurrence rate of STAS increased as the PSC increased. STAS was only observed in part-solid nodules with a PSC greater than 25%. Among the CT morphological features, lobulation was an independent influencing factor of lung cancer with STAS (OR =3.513; P<0.05), and persistent indistinct margin ground-glass opacity around the primary lesion of lung cancer (21 of 121, 17.36%) and satellite foci (9 of 121, 7.44%) strongly indicated the existence of STAS., Conclusions: The clinical, pathological and CT features of STAS may guide clinicians to develop appropriate strategies and improve the survival rate of patients., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tlcr.amegroups.com/article/view/10.21037/tlcr-24-715/coif). The authors have no conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)