A novel modified nano-alumina composite sol for potential application in forest firefighting.

Herein, modified ammonium polyphosphate wrapped nano-alumina (mAPP@Als) was first synthesized and then dispersed in traditional fire extinguishing solution (FES) to fabricate a FES-mAPP@Als composite sol. It was found that the phosphorus-silica containing units were attached onto the nano-alumina surface, and the mAPP@Als particles showed excellent dispersion level in FES with a single-domain particle size distribution range. Due to the synergistic effects of the phosphorus-nitrogen and silica-alumina flame retardant components, FES-mAPP@Als (5% concentration) coated wood exhibited improved limiting oxygen index (33.2%) and carbonization ability, and depressed heat release (41.9%) and smoke production (10.7%), as compared to the pristine wood. In addition, the FES-mAPP@Als composite sol showed enhanced fire-extinguishing and anti-reignition capacities compared to the FES. This research offers a novel composite sol fire extinguishing agent for fighting forest fires.

Facile Strategy to Fabricate the Flame Retardant Polyamide 66 Fabric Modified with an Inorganic-Organic Hybrid Structure.

Recently, traditional flame retardant finishing with a single metal compound has been rarely applied owing to its low effectiveness and durability. This study reports metal ion finishing in combination with surface photografting modification (M/P technology) as a novel approach to incorporate an inorganic-organic hybrid structure containing an Fe3+ ion onto the surface of the polyamide (PA) 66 fabric. Specifically, the PA fabric was first surface-modified in the presence of acrylic acid (AA) and N,N'-methylene bisacrylamide (MBAAn) during photografting pretreatment under UV irradiation (step I), then further reacted with the Fe3+ ion in the metal ion finishing (step II). After treatment with M/P technology, the fabric exhibits the required excellent flame retardancy and dripping resistance. Here, flame retardant tests show that the treated PA fabric has the highest limiting oxygen index (LOI) value of 33.4 and no melt dripping during combustion. An interesting inorganic/organic composite thermal barrier consisting of an inorganic iron oxide nanoparticle (NP) outer layer and an organic micro-intumescent inner layer can be observed on the surface of the burnt fabric. This structure could be responsible for the significant enhancement in the fire performance of the treated fabric. Importantly, the treated fabric is also highly stable during the laundering procedure, which could retain a high Fe/C ratio and an acceptable LOI value of 27.8 after washing 45 times. This confirms the achievement of durable flame retardancy after treatment with M/P technology, and its possible interaction mechanism has been discussed here.

[Application of computer-aided diagnosis in early detection of pulmonary nodules based on digital chest radiograph].

This study aims to explore the clinical value of the computer-aided diagnosis (CAD) system for early detection of the pulmonary nodules on digital chest X-ray. A total of 100 cases of digital chest radiographs with pulmonary nodules of 5-20 mm diameter were selected from Pictures Archiving and Communication System (PACS) database in West China Hospital of Sichuan University were enrolled into trial group, and other 200 chest radiographs without pulmonary nodules as control group. All cases were confirmed by CT examination. Firstly, these cases were diagnosed by 5 different-seniority doctors without CAD, and after three months, these cases were re-diagnosed by the 5 doctors with CAD. Subsequently, the diagnostic results were analyzed by using SPSS statistical methods. The results showed that the sensitivity and specificity for detecting pulmonary nodules tended to be improved by using the CAD system, especially for specificity, but there was no significant difference before and after using CAD system.