针对目前我国冬枣人工分选效率低、工人劳动强度大和分级效果不准确等问题,研究一种冬枣智能分选系统。该系统基于Openmv视觉处理技术,以Arduino mega 2560单片机为控制核心,实现对冬枣快速统一的色选及大小分选。经过样机试验数据验证...针对目前我国冬枣人工分选效率低、工人劳动强度大和分级效果不准确等问题,研究一种冬枣智能分选系统。该系统基于Openmv视觉处理技术,以Arduino mega 2560单片机为控制核心,实现对冬枣快速统一的色选及大小分选。经过样机试验数据验证,该系统能够有效地实现冬枣分选功能,单通道分选速度达到60颗/s以上,分选准确率提高至96%以上,漏检和错检概率降低到4%以下,且能够减少用工数量和降低劳动强度,具有良好的推广应用前景。展开更多
以异山梨醇为基体,合成了不同分子结构的生物基增塑剂二丁酸异山梨酯与二丁烯酸异山梨酯,并用于聚氯乙烯(PVC)改性。对所制生物基增塑剂进行分子结构表征,考察了其对PVC力学性能和加工流动性的影响。结果表明:两种生物基增塑剂均能提高...以异山梨醇为基体,合成了不同分子结构的生物基增塑剂二丁酸异山梨酯与二丁烯酸异山梨酯,并用于聚氯乙烯(PVC)改性。对所制生物基增塑剂进行分子结构表征,考察了其对PVC力学性能和加工流动性的影响。结果表明:两种生物基增塑剂均能提高PVC的冲击强度,且二丁酸异山梨酯增塑效果优于二丁烯酸异山梨酯。每100 g PVC中增塑剂添加量均为10 g时,二丁酸异山梨酯增韧PVC的冲击强度为2.91 kJ/m^(2),较参比试样(增塑剂为邻苯二甲酸二丁酯)提高了38%。展开更多
Tomato yellow leaf curl viruses belong to Begomoviruses of geminiviruses. In this work, we first found and demonstrated that the small circular DNA molecules were derived from Chinese tomato yellow leaf curl viruses (...Tomato yellow leaf curl viruses belong to Begomoviruses of geminiviruses. In this work, we first found and demonstrated that the small circular DNA molecules were derived from Chinese tomato yellow leaf curl viruses (TYLCV-CHI). These small circular DNA molecules are about 1.3 kb, which are half the full-length of TYLCV-CHI DNA A. It was shown by sequence determination and analysis that there was unknown-origin sequence insertion in the middle of the small molecules. These sequences of unknown-origin were neither homologous to DNA A nor to DNA B, and were formed by recombination of virus DNA and plant DNA. Although various defective molecules contained different unknown-origin sequence insertion, all the molecules contained the intergenic region and part of the AC1 (Rep) gene. But they did not contain full ORF.展开更多
Geminivirus is a kind of single-stranded DNA virus. Experimental results from tomato golden mosaic virus (TGMV) showed that expression pattern of coat protein gene (cp) promoter was phloem specifically expressed. In t...Geminivirus is a kind of single-stranded DNA virus. Experimental results from tomato golden mosaic virus (TGMV) showed that expression pattern of coat protein gene (cp) promoter was phloem specifically expressed. In this note, the studies on cp promoter of cotton leaf curl virus (CLCuV) which is found and identified recently suggest that the promoter is not phloem specifically expressed. The expressing activity of gus gene driven by the promoter exists not only in phloem but also in mesophyll tissues and root tip meristem. Transient expression suggests that cp promoter transactivated by AC2 shows expressing activity in mesophyll and vascular tissue of leaf vein.展开更多
Sequence analysis of virus isolation DNA of tobacco leaf curl disease shows that there is the second geminivirus (not Chinese Tobacco Leaf Curl Virus, TbLCV-CHI) that causes tobacco leaf curl disease in the field in t...Sequence analysis of virus isolation DNA of tobacco leaf curl disease shows that there is the second geminivirus (not Chinese Tobacco Leaf Curl Virus, TbLCV-CHI) that causes tobacco leaf curl disease in the field in the Guangxi Zhuang Autonomous Region, China. This virus DNA-A contains 2 734 nt. Large intergenic region (LIR) contains 269 nt, the virus sense strand contains 2 open reading frames (ORFs): AV1 (115 aa) and AV2 (coat protein gene, CP, 256 aa), and the complementary sense strand contains 4 ORFs: AC1 (replicase gene, 361 aa), AC2 (transactivator, 134 aa), ACS (134 aa) and AC4 (97 aa). The virus belongs to one kind of subgroup III gemini- viruses from old world, and could be the Chinese tomato yellow leaf curl virus (TYLCV-CHI).展开更多
Tobacco mosaic virus (TMV) has the potential to highly express foreign gene. A novel TMV-based in trans expression system was constructed. A TMV mutant TSHc had its coat protein replaced with hepatitis C vir黶 (HCV) c...Tobacco mosaic virus (TMV) has the potential to highly express foreign gene. A novel TMV-based in trans expression system was constructed. A TMV mutant TSHc had its coat protein replaced with hepatitis C vir黶 (HCV) core antigen gene. Anotherr TMV mutant TSBD was repli-case-defective. Coinfection of the two mutants could cause systemic infection in tobacco plants by in trans complementation of their functions. TSHc could effectively replicate and assemble to viral particles, which were a little longer than that of wild-type TMV. HCV core antigen was expressed in whole tobacco plants. A similar expression level of HCV core antigen was detected on serial passages, which suggested that this viral expression system be stable.展开更多
文摘针对目前我国冬枣人工分选效率低、工人劳动强度大和分级效果不准确等问题,研究一种冬枣智能分选系统。该系统基于Openmv视觉处理技术,以Arduino mega 2560单片机为控制核心,实现对冬枣快速统一的色选及大小分选。经过样机试验数据验证,该系统能够有效地实现冬枣分选功能,单通道分选速度达到60颗/s以上,分选准确率提高至96%以上,漏检和错检概率降低到4%以下,且能够减少用工数量和降低劳动强度,具有良好的推广应用前景。
文摘以异山梨醇为基体,合成了不同分子结构的生物基增塑剂二丁酸异山梨酯与二丁烯酸异山梨酯,并用于聚氯乙烯(PVC)改性。对所制生物基增塑剂进行分子结构表征,考察了其对PVC力学性能和加工流动性的影响。结果表明:两种生物基增塑剂均能提高PVC的冲击强度,且二丁酸异山梨酯增塑效果优于二丁烯酸异山梨酯。每100 g PVC中增塑剂添加量均为10 g时,二丁酸异山梨酯增韧PVC的冲击强度为2.91 kJ/m^(2),较参比试样(增塑剂为邻苯二甲酸二丁酯)提高了38%。
文摘Tomato yellow leaf curl viruses belong to Begomoviruses of geminiviruses. In this work, we first found and demonstrated that the small circular DNA molecules were derived from Chinese tomato yellow leaf curl viruses (TYLCV-CHI). These small circular DNA molecules are about 1.3 kb, which are half the full-length of TYLCV-CHI DNA A. It was shown by sequence determination and analysis that there was unknown-origin sequence insertion in the middle of the small molecules. These sequences of unknown-origin were neither homologous to DNA A nor to DNA B, and were formed by recombination of virus DNA and plant DNA. Although various defective molecules contained different unknown-origin sequence insertion, all the molecules contained the intergenic region and part of the AC1 (Rep) gene. But they did not contain full ORF.
文摘Geminivirus is a kind of single-stranded DNA virus. Experimental results from tomato golden mosaic virus (TGMV) showed that expression pattern of coat protein gene (cp) promoter was phloem specifically expressed. In this note, the studies on cp promoter of cotton leaf curl virus (CLCuV) which is found and identified recently suggest that the promoter is not phloem specifically expressed. The expressing activity of gus gene driven by the promoter exists not only in phloem but also in mesophyll tissues and root tip meristem. Transient expression suggests that cp promoter transactivated by AC2 shows expressing activity in mesophyll and vascular tissue of leaf vein.
文摘Sequence analysis of virus isolation DNA of tobacco leaf curl disease shows that there is the second geminivirus (not Chinese Tobacco Leaf Curl Virus, TbLCV-CHI) that causes tobacco leaf curl disease in the field in the Guangxi Zhuang Autonomous Region, China. This virus DNA-A contains 2 734 nt. Large intergenic region (LIR) contains 269 nt, the virus sense strand contains 2 open reading frames (ORFs): AV1 (115 aa) and AV2 (coat protein gene, CP, 256 aa), and the complementary sense strand contains 4 ORFs: AC1 (replicase gene, 361 aa), AC2 (transactivator, 134 aa), ACS (134 aa) and AC4 (97 aa). The virus belongs to one kind of subgroup III gemini- viruses from old world, and could be the Chinese tomato yellow leaf curl virus (TYLCV-CHI).
文摘Tobacco mosaic virus (TMV) has the potential to highly express foreign gene. A novel TMV-based in trans expression system was constructed. A TMV mutant TSHc had its coat protein replaced with hepatitis C vir黶 (HCV) core antigen gene. Anotherr TMV mutant TSBD was repli-case-defective. Coinfection of the two mutants could cause systemic infection in tobacco plants by in trans complementation of their functions. TSHc could effectively replicate and assemble to viral particles, which were a little longer than that of wild-type TMV. HCV core antigen was expressed in whole tobacco plants. A similar expression level of HCV core antigen was detected on serial passages, which suggested that this viral expression system be stable.