Objective To make the preparation method for coatings more convenient in the field where the requirements for tritium permeation resistance are not high, this paper proposes a method for preparing Al-Al₂O₃ tritium permeation barriers by thermal spraying technology and conducts a performance analysis. Methods The tritium permeation resistance and adhesion of Al-Al₂O₃ coatings prepared by thermal spraying were verified by experiments. Results The tritium permeability was reduced by one order of magnitude after a 0.2-mm Al-Al₂O₃ coating was sprayed on the stainless steel surface, and the tritium permeation resistance had no significant improvement with the increase in coating thickness; the adhesion of the coating was determined in the range of 5-10 N by scratch tests. Conclusion In this paper, a simple preparation method for tritium permeation barrier is proposed, and the tritium permeation resistance performance of Al-Al₂O₃ coatings prepared by thermal spraying technology is determined, which provides a reference for the selection of tritium permeation barrier in the field of tritium-containing solid waste storage.

Objective:To analyze clinical and histopathological features of cutaneous horns, and to explore their relationship.Methods:A total of 204 patients with cutaneous horns confirmed by clinical and histopathological examinations were collected from Department of Pathology, Shanghai Skin Disease Hospital between January 2014 and May 2020, and their clinical and histopathological data were retrospectively analyzed.Results:Among 204 patients, there were 88 males and 116 females with the age being 70.47±14.76 years and median ( P25, P75) course being 6 (6, 24) months. Cutaneous horns were solitary in 201 cases, and multiple in 3. There were a total of 207 cutaneous horns, including 163 (78.74%) located on the head, face and neck, 18 (8.70%) on the trunk and 26 (12.56%) on the extremities. According to histopathological conditions at the base of the cutaneous horns, 154 (74.40%) cutaneous horns were considered to arise from benign lesions (named as benign horns) , including viral warts ( n=129) , seborrheic keratosis ( n=15) , inverted follicular keratosis ( n=3) , trichilemmomas ( n=5) , pyogenic granuloma ( n=1) and calcifying epithelioma ( n=1) ; 40 (19.32%) were considered to arise from premalignant lesions (actinic keratosis) and named as premalignant horns; 13 (6.28%) were considered to arise from malignant lesions (named as malignant horns) , including Bowen′s disease ( n=5) and squamous cell carcinoma ( n=8) . The average ages of patients with premalignant and malignant horns were significantly higher than those of patients with benign horns ( H=4.05, 3.16, respectively, both P < 0.01) . The base width of the malignant horns was significantly higher than that of the premalignant and benign horns ( H=2.74, 3.49, P < 0.05, 0.01, respectively) , and there was no significant difference between the premalignant and benign horns ( H=0.73, P > 0.05) . The height to base width ratio was significantly lower in the premalignant and malignant horns than in the benign horns ( H=4.06, 3.72, respectively, both P < 0.01) . The incidence rate of basal erythema was significantly higher in the premalignant and malignant horns than that in the benign horns ( χ2=29.57, 6.23, P < 0.01, 0.05, respectively) , and bleeding and crusting occurred more frequently in the malignant horns compared with the benign horns ( χ2=4.89, P < 0.05) . Conclusions:The base of most cutaneous horns is benign, which mainly includes viral warts, and premalignant and malignant horns account for about a quarter. Male, older age, wide base, low ratio of the height to base width, basal erythema, history of bleeding and crusting can serve as clues to early recognition of malignant lesions at the base of cutaneous horns.