Main factors influencing anti-ultraviolet performance of woven fabrics are investigated. By means of detailed arrangement of sample design, sample making, testing and analyzing, it shows that fiber materials, fabric c...Main factors influencing anti-ultraviolet performance of woven fabrics are investigated. By means of detailed arrangement of sample design, sample making, testing and analyzing, it shows that fiber materials, fabric compactness, fabric weave and yarn type are the four important factors influencing anti-UV performance of woven fabric, but with different effects. Among them fiber material is the most important factor. For the common fiber materials used, it shows that the anti-UV performance of polyester is comparatively better than others. Once fiber material is determined, fabric with medium float weave and high compactness can offer a good anti-UV performance. The anti-UV performance of fabric with ＂anti-UV＂ filament yarn is better than that with ＂anti-UV＂ staple yarn. The anti-UV property of fabrics with untwisted filament yams is better than that with twist counterparts.展开更多
Objective： We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods： The SI Virtual Water Phantom was used to monitor medium of do...Objective： We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods： The SI Virtual Water Phantom was used to monitor medium of dose. PTW ionization chamber was used to detect the dose. AP-PA （10 cmx 10 cm） and SAD technique were adopted. Monitoring dose of different locations with different energy of radioactive ray in AP and PA respectively with and without contraceptive ring, repeated 5 times. Results： Dose of with contraceptive ring was lower than that of without contraceptive ring in AP 6 MV- X-ray （P 〈 0.05）, while in PA was no obvious difference （P 〉 0.05）. Dose of except for the center was higher than that of without contraceptive ring in AP and PA 15 MV-X-ray （P 〈 0.05）. For locations, doses of the upper, the left and right were higher than that of the center in AP 6 MV-X-ray （P 〈 0.05）, while in PA was lower （P 〉 0.05）. In AP and PA 15 MV-X-ray, doses of the upper, the left and right was higher than that of the center （P 〈 0.05）. Conclusion： Metallic contraceptive ring would effect the dose distribution of radioactive ray, but influence degree related to locations of contraceptive ring and energy of radioactive ray.展开更多
尽管CT检查仅占所有检查的2％，而对于公众诊断性成像的接收剂量，CT却占20％左右。而具有10mSv有效剂量的成人腹部检查会增加致癌风险1/2000。儿童对于放射线影响的灵敏度是中年人的10倍多，女孩比男孩更敏感。剂量增加的原因有：CT应...尽管CT检查仅占所有检查的2％，而对于公众诊断性成像的接收剂量，CT却占20％左右。而具有10mSv有效剂量的成人腹部检查会增加致癌风险1/2000。儿童对于放射线影响的灵敏度是中年人的10倍多，女孩比男孩更敏感。剂量增加的原因有：CT应用的偏差、使用方便的结果、多层CT的危机、未意识到“脱耦合效应”。医护人员要进行很好的培训，要意识到不断涌现的资料及实践中潜在的变化，根据进展修正方案。象进行传统X射线摄影一样，“合理使用低剂量(as low as reasonably achievable，AIARA)”原则也很适合于CT的应用。展开更多
文摘Main factors influencing anti-ultraviolet performance of woven fabrics are investigated. By means of detailed arrangement of sample design, sample making, testing and analyzing, it shows that fiber materials, fabric compactness, fabric weave and yarn type are the four important factors influencing anti-UV performance of woven fabric, but with different effects. Among them fiber material is the most important factor. For the common fiber materials used, it shows that the anti-UV performance of polyester is comparatively better than others. Once fiber material is determined, fabric with medium float weave and high compactness can offer a good anti-UV performance. The anti-UV performance of fabric with ＂anti-UV＂ filament yarn is better than that with ＂anti-UV＂ staple yarn. The anti-UV property of fabrics with untwisted filament yams is better than that with twist counterparts.
文摘Objective： We studied the relationship between impact of dose distribution and energy of radioactive ray in teletherapy with contraceptive ring. Methods： The SI Virtual Water Phantom was used to monitor medium of dose. PTW ionization chamber was used to detect the dose. AP-PA （10 cmx 10 cm） and SAD technique were adopted. Monitoring dose of different locations with different energy of radioactive ray in AP and PA respectively with and without contraceptive ring, repeated 5 times. Results： Dose of with contraceptive ring was lower than that of without contraceptive ring in AP 6 MV- X-ray （P 〈 0.05）, while in PA was no obvious difference （P 〉 0.05）. Dose of except for the center was higher than that of without contraceptive ring in AP and PA 15 MV-X-ray （P 〈 0.05）. For locations, doses of the upper, the left and right were higher than that of the center in AP 6 MV-X-ray （P 〈 0.05）, while in PA was lower （P 〉 0.05）. In AP and PA 15 MV-X-ray, doses of the upper, the left and right was higher than that of the center （P 〈 0.05）. Conclusion： Metallic contraceptive ring would effect the dose distribution of radioactive ray, but influence degree related to locations of contraceptive ring and energy of radioactive ray.
文摘尽管CT检查仅占所有检查的2％，而对于公众诊断性成像的接收剂量，CT却占20％左右。而具有10mSv有效剂量的成人腹部检查会增加致癌风险1/2000。儿童对于放射线影响的灵敏度是中年人的10倍多，女孩比男孩更敏感。剂量增加的原因有：CT应用的偏差、使用方便的结果、多层CT的危机、未意识到“脱耦合效应”。医护人员要进行很好的培训，要意识到不断涌现的资料及实践中潜在的变化，根据进展修正方案。象进行传统X射线摄影一样，“合理使用低剂量(as low as reasonably achievable，AIARA)”原则也很适合于CT的应用。
