The NDT detection of knobs of logs and timbers was conducted by using computer video technique.The key detection points were taken from these knobs for mathematics description. It can make the drawing ofthese knobs qu...The NDT detection of knobs of logs and timbers was conducted by using computer video technique.The key detection points were taken from these knobs for mathematics description. It can make the drawing ofthese knobs quantitatively and establish corresponding mathematics models. Using the grayness of pictures andcartoon if eatment made the mathemstics reappearance of the knobs become more access to video pictures.展开更多
The betatron tune is an important parameter in a storage ring to enable stable operation. A tune adjustment tool with a small impact on the beam dynamics is useful for user operation and machine studies. Therefore, a ...The betatron tune is an important parameter in a storage ring to enable stable operation. A tune adjustment tool with a small impact on the beam dynamics is useful for user operation and machine studies. Therefore, a tune knob is developed for the Hefei light source-II(HLS-II) storage ring. Owing to the compactness of the storage ring, a global adjustment mechanism is adopted. To reduce the impact on beam injection, only quadrupole families outside the injection section are used by the tune knob, and the b functions of the injection section remain unchanged. A code is developed based on the accelerator simulation software, MAD-X, to calculate the adjustment of the quadrupole strengths. The accelerator toolbox is used to double check the accuracy of the tune knob. Online measurement of the tune knob is also performed. The result shows that the tune knob works well when the tune is adjusted in a specific range. Betatron coupling measurement is also carried out, showing an application of the tune knob on machine studies. In this paper, the development of the tune knob and its experimental results in the HLS-II storage ring are reported in detail.展开更多
Knobs are blocks of heterochromatin present on chromosomes of maize （Zea mays L.） and its relatives that have effects on the frequency of genetic recombination, as well as on chromosome behavior. Knob heterozygosity...Knobs are blocks of heterochromatin present on chromosomes of maize （Zea mays L.） and its relatives that have effects on the frequency of genetic recombination, as well as on chromosome behavior. Knob heterozygosity and instability in six maize inbred lines and one Z. diploperennis Iltis Doebley line were investigated using the fluorescence in situ hybridization （FISH） technique with knob-associated tandem repeats （180 bp and 350 bp （TR- 1）） as probes. Signals of seven heterozygous knobs containing 180- bp repeats and of one heterozygous knob containing TR- 1 were captured in chromosomes of all materials tested according to the results of FISH, which demonstrates that the 180-bp repeat is the main contributor to knob heterozygosity compared with the TR- 1 element. In addition, one target cell with two TR- 1 signals on one homolog of chromosome 2L, which was different from the normal cells in the maize inbred line GB57, was observed, suggesting knob duplication and an instability phenomenon in the maize genome.展开更多
IN 1964, the tomb of Hua Fang was excavated at a construction site in Beijing’s western suburbs. Hua Fang was the wife of Wang Jun, who was a prefectural governor of Youzhou (an ancient name for Beijing) during the W...IN 1964, the tomb of Hua Fang was excavated at a construction site in Beijing’s western suburbs. Hua Fang was the wife of Wang Jun, who was a prefectural governor of Youzhou (an ancient name for Beijing) during the Western Jin Dynasty. Found in the tomb were a bone ruler and a silver bell in good condition, as well as a packet of half-transparent pieces of glassware. The fragments were restored by experts in 1984 into a complete vessel, which is currently displayed in the Capital Museum.展开更多
FOR Wang Zhao and Ren Meiying, their marriage has a magic power pushing them towards a common cause. Wang and Ren met each other in 1983. At that time Wang was working with an oil company at Langfang, 58
文摘The NDT detection of knobs of logs and timbers was conducted by using computer video technique.The key detection points were taken from these knobs for mathematics description. It can make the drawing ofthese knobs quantitatively and establish corresponding mathematics models. Using the grayness of pictures andcartoon if eatment made the mathemstics reappearance of the knobs become more access to video pictures.
基金supported by the National Natural Science Foundation of China(Nos.11375177 and 11705200)
文摘The betatron tune is an important parameter in a storage ring to enable stable operation. A tune adjustment tool with a small impact on the beam dynamics is useful for user operation and machine studies. Therefore, a tune knob is developed for the Hefei light source-II(HLS-II) storage ring. Owing to the compactness of the storage ring, a global adjustment mechanism is adopted. To reduce the impact on beam injection, only quadrupole families outside the injection section are used by the tune knob, and the b functions of the injection section remain unchanged. A code is developed based on the accelerator simulation software, MAD-X, to calculate the adjustment of the quadrupole strengths. The accelerator toolbox is used to double check the accuracy of the tune knob. Online measurement of the tune knob is also performed. The result shows that the tune knob works well when the tune is adjusted in a specific range. Betatron coupling measurement is also carried out, showing an application of the tune knob on machine studies. In this paper, the development of the tune knob and its experimental results in the HLS-II storage ring are reported in detail.
文摘Knobs are blocks of heterochromatin present on chromosomes of maize （Zea mays L.） and its relatives that have effects on the frequency of genetic recombination, as well as on chromosome behavior. Knob heterozygosity and instability in six maize inbred lines and one Z. diploperennis Iltis Doebley line were investigated using the fluorescence in situ hybridization （FISH） technique with knob-associated tandem repeats （180 bp and 350 bp （TR- 1）） as probes. Signals of seven heterozygous knobs containing 180- bp repeats and of one heterozygous knob containing TR- 1 were captured in chromosomes of all materials tested according to the results of FISH, which demonstrates that the 180-bp repeat is the main contributor to knob heterozygosity compared with the TR- 1 element. In addition, one target cell with two TR- 1 signals on one homolog of chromosome 2L, which was different from the normal cells in the maize inbred line GB57, was observed, suggesting knob duplication and an instability phenomenon in the maize genome.
文摘IN 1964, the tomb of Hua Fang was excavated at a construction site in Beijing’s western suburbs. Hua Fang was the wife of Wang Jun, who was a prefectural governor of Youzhou (an ancient name for Beijing) during the Western Jin Dynasty. Found in the tomb were a bone ruler and a silver bell in good condition, as well as a packet of half-transparent pieces of glassware. The fragments were restored by experts in 1984 into a complete vessel, which is currently displayed in the Capital Museum.
文摘FOR Wang Zhao and Ren Meiying, their marriage has a magic power pushing them towards a common cause. Wang and Ren met each other in 1983. At that time Wang was working with an oil company at Langfang, 58
