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In recent years, 64Cu has received extensive attention along with its growing application in nuclear medicine positron emission tomography (PET) diagnosis. A 64Cu automatic separation apparatus adapted to the Cyclone-30 cyclotron was developed to realize the process automation from target dissolution to nuclide separation and purification for stable 64Cu production at large scale. The apparatus consists of a tank for target dissolution and a system for separation and purification. The operation interface, programming language and specific programming instructions were determined by programming design. Based on the established separation and purification process of 64Cu, the apparatus was designed followed by assembling and testing. After the process parameters of the apparatus were confirmed through a series of conditional experiments, the hot verification experiments at small-scale and three batches of mass production process verification were carried out consecutively, showing that this self-developed apparatus has steady function and can realize distant control. The whole separation process could be finished in 3 h. The radiochemical recovery of 64Cu (after calibration) is greater than 90%, which meets the expected goal of the design. The 64Cu product was tested with over 95% of radiochemical purity, higher than 99.9% of radio nuclidic purity. The contents of impurities such as iron, copper and zinc were less than 1.5 μg/GBq, while cobalt, gold and nickel were less than 0.5 μg/GBq, which meets the requirements of group standard and can be used for preparation of 64Cu radiopharmaceuticals. In conclusion, this self-developed apparatus has low cost and independent intellectual property rights, and its performance and the product quality of 64Cu are comparable to other competitive foreign products. Compared with the manual separation process, the automatic one has significant advantages in terms of the stability of product quality, the process controllability, the time-consuming and the radiation protection of operators. At present, the apparatus has already been used in 64Cu production routinely.

This work investigated the composites (PA6/BF) made of basalt fiber (BF) and nylon 6. To improve the interfacial bonding between the fibers and the polymer matrix, and to enhance the thermal and mechanical properties of the composites, polyhedral oligosilsesquioxanes (POSS) with epoxide groups was introduced to modify the surface of BFs using the slurry coating method. It is revealed that the mechanical properties of the composites increased and then decreased with increasing POSS coating. The composite PA6/BF‐POSS3 with BFs modified with a POSS solution of 3.0 wt% showed the best properties. The tensile strength of PA6/BF‐POSS3 was 130.8 MPa, 26.4% higher than that of the PA6/BF and 126.3% higher than that of neat PA6. In addition, PA6/BF‐POSS3 exhibited a 5% weight loss temperature of 417.7, 35.6°C higher than that of PA6/BF. The chemical bonding formed between the amide and epoxide groups, and the hydrogen bonding formed between the amide groups and hydroxyl groups were believed to be the main reasons for the improved interfacial interaction and improved properties. [ABSTRACT FROM AUTHOR]

Due to the advantages of non-toxicity, high chemical stability, high activity and low cost, TiO2 is deemed as ideal material for photocatalytic degradation. However, due to its relatively high band-gap energy, anatase TiO2 can only absorb UV light and light with higher energy. In this work, the anatase TiO2 particles were decorated with two organic photosensitizers hemin and eosin Y. The morphology and chemical structure of the composites were verified by SEM, XRD patterns and Raman spectra, the light absorption ability and generation of free radicals were also investigated. The band-gap energy of TiO2, hemin/TiO2 and EY/TiO2 were found to be 2.82 eV, 0.72 eV and 0.95 eV, respectively. Additionally, absorption of more visible light and generation of more superoxide radicals were achieved after decoration of photosensitizers. Consequently, the photocatalytic degradation activity was largely improved, when the TiO2 particles was decorated with 3% of hemin, the degradation rate of methyl blue reached 76.89% and 63.82% in 120 min under UV light and visible light, respectively, which were 1.86 and 1.84 times that of neat TiO2. Comparatively, the ferric ions in hemin may capture the electrons generated by TiO2 and then deliver the electrons to oxygen to generate more superoxide radicals, thus hemin/TiO2 exhibits higher photocatalytic degradation activity than EY/TiO2. [ABSTRACT FROM AUTHOR]

Basalt fiber (BF) faces challenges in enhancing polymer properties due to its smooth surface and chemical inertness. In order to improve the interfacial bonding between BF and polypropylene (PP) matrix and enhance the effect of BF on PP, the surface of BF was modified by electron beam irradiation and nano-silica (nano-SiO2). The results show that during the irradiation process, the hydroxyl groups on the surface of BF increases, the binding ability of BF to nano-SiO2 is improved, and more PP crystallization sites are formed on the surface of BF, which increase the crystallinity of PP matrix from 36.66% to 48.30%. During the irradiation process, the surface of BF is rougher, and the interfacial friction between BF and PP molecular chains is improved. When irradiation dose is 400 kGy, the tensile strength of modified BF/PP is 29.2% and 20.3% higher than that of pure PP and unmodified BF/PP, respectively. When the irradiation dose is 200 kGy, the thermal decomposition temperature of modified BF/PP is 6.4 °C and 2.2 °C higher than that of pure PP and unmodified BF/PP, respectively. [ABSTRACT FROM AUTHOR]