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This work investigates the influence of initial microstructure characteristics on the creep age forming behavior, mechanical anisotropy and fatigue crack growth resistance of creep age formed components. Components made by 2050 Al–Li alloy with fine, coarse and fibrous grain structures were prepared. The results indicate that the components with fibrous grains significantly increases the creep strain, which were generated by large-strain pre-deformation. Additionally, these components exhibit the highest yield and ultimate tensile strengths. On the other hand, components with coarse grains demonstrate superior fatigue crack growth resistance compared to other microstructures. Conversely, components with fine grains exhibit the lowest in-plane anisotropy value. The fatigue crack growth resistance of the three microstructures follows a descending order of coarse grains, fine grains, and fibrous grains. For applications requiring less anisotropy, the AA2050 alloy with fine grains is recommended. Conversely, the alloy with coarse grains is suitable for components subjected to cyclic loading. Lastly, the alloy with fibrous grains is ideal for structural components due to its high ultimate tensile strength and creep strain. [ABSTRACT FROM AUTHOR]

Polyester/cotton (PET/CO) fabrics usually burn more violently than single-component fabric due to significant differences of two components as well as "wick effect" during combustion process. Hence, it is very challenging to impart PET/CO fabrics excellent flame retardancy. In this work, a new monomer (ethoxy piperazine (phenyl) phosphoryl ethyl methacrylate, EPPEM) containing multiple unsaturated double bonds was synthesized. As EPPEM contained varied synergistic flame retardant components of phosphorus, nitrogen, and benzene ring, it was expected to form a dense cross-linked network structure on the surface of the fabrics by UV curing to prepare PET/CO fabrics with good flame retardancy and washing resistance. The limiting oxygen index (LOI) value of treated PET/CO fabrics increased up to 27.2% from 17.8% of control sample, which still reached 26.6% after 25 laundering cycles, indicating excellent flame retardancy and water-laundering resistance. Raman spectroscopy, thermogravimetric analysis coupled with Fourier transform infrared analysis and thermogravimetric mass spectrometry indicated that EPPEM promoted the production of more non-combustible compounds during pyrolysis process, such as H2O and CO2. Furthermore, EPPEM decomposed to produce acidic substances which promoted dehydration and coke formation of PET/CO fabrics, thereby preventing exchange of heat and combustible gas. On the basis of the results, a two-phase flame-retardant mechanism of EPPEM/UV-curable system for PET/CO fabrics was proposed. [ABSTRACT FROM AUTHOR]

The article presents a study which discusses the bioactive components of wet marine sponges Axinella, which belongs to the family of Axinellidae. It states that Axinella was found to consist six chemical compounds which were determined using nuclear magnetic resonance (NMR) spectroscopy. It adds that the ecological origin and secondary metabolites of Axinella are anticipated to be useful for further chemotaxonomic research about marine sponges.

An abstract of the article "A New N-Acyl Taurine from the South China Sea Marine Sponge Callyspongia sp" by Riming Huang, Yinning Chen, Xuefeng Zhou, Xianwen Yang, and Yonghong Liu is presented.

The article discusses a study which investigates the bioactive chemical components of the starfish Stellaster equestris, with seven compounds which were isolated from the S. equestris' ethyl acetate extracts. The study used petroleum ether, ethyl acetate, and n-butanol to partition the ethanol extract. Results show that the isolated compounds has showed moderate activity against Escherichia coli.

The article presents a study on marine sponge Callyspongia sp., which is widely distributed and is made up of various bioactive components. It states that the wet marine sponge Callyspongia sp. was extracted with ethanol and was evaporated to give a syrupy residue with ethyl acetate fraction. The study used spectral analysis which identified the isolated compounds. The results show that the isolated compounds from Callyspongia sp. were identified as spongothymidine, spongouridine and thymine.