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排序方式: 共有2093条查询结果,搜索用时 15 毫秒
991.
992.
Linkin VM Kerzhanovich VV Lipatov AN Shurupov AA Seiff A Ragent B Young RE Ingersoll AP Crisp D Elson LS Preston RA Blamont JE 《Science (New York, N.Y.)》1986,231(4744):1420-1422
Thermal structure measurements obtained by the two VEGA balloons show the Venus middle cloud layer to be generally adiabatic. Temperatures measured by the two balloons at locations roughly symmetric about the equator differed by about 6.5 kelvins at a given pressure. The VEGA-2 temperatures were about 2.5 kelvins cooler and those of VEGA-1 about 4 kelvins warmer than temperatures measured by the Pioneer Venus Large Probe at these levels. Data taken by the VEGA-2 lander as it passed through the middle cloud agreed with those of the VEGA-2 balloon. Study of individual frames of the balloon data suggests the presence of multiple discrete air masses that are internally adiabatic but lie on slightly different adiabats. These adiabats, for a given balloon, can differ in temperature by as much as 1 kelvin at a given pressure. 相似文献
993.
994.
Blamont JE Young RE Seiff A Ragent B Sagdeev R Linkin VM Kerzhanovich VV Ingersoll AP Crisp D Elson LS Preston RA Golitsyn GS Ivanov VN 《Science (New York, N.Y.)》1986,231(4744):1422-1425
Both VEGA balloons encountered vertical winds with typical velocities of 1 to 2 meters per second. These values are consistent with those estimated from mixing length theory of thermal convection. However, small-scale temperature fluctuations for each balloon were sometimes larger than predicted. The approximate 6.5-kelvin difference in temperature consistently seen between VEGA-1 and VEGA-2 is probably due to synoptic or planetary-scale nonaxisymmetric disturbances that propagate westward with respect to the planet. There is also evidence from Doppler data for the existence of solar-fixed nonaxisymmetric motions that may be thermal tides. Surface topography may influence atmospheric motions experienced by the VEGA-2 balloon. 相似文献
995.
Sung-Il Kim Moon Young Kim Kyujung Van Yeong-Ho Lee Hong Sig Kim Chun Mei Cai Bong-Soo Park Hak-Soo Seo Suk-Ha Lee 《Euphytica》2011,177(3):355-363
The development of soybean varieties that lack the β-conglycinin α′ subunit is an attractive goal because the β-conglycinin
α′ subunit exerts a negative influence on nutrition and tofu gelation, and is also a major allergen. We sought to develop
a co-dominant DNA marker for the β-conglycinin α′ subunit (Cgy-1) gene for use in marker-assisted selection (MAS). We identified a deleted sequence responsible for the null allele of Cgy-1 in a soybean variety lacking the β-conglycinin α′ subunit known as ‘Keburi’. The deletion spanned 12,998 bp and included
Cgy-1 and its incomplete tandem duplicate on chromosome 10. Based on the Cgy-1 sequence from both the Williams 82 soybean reference sequence and the Keburi variety, a set of three allele-specific primers
was designed for multiplex PCR assay. These primers enabled allelic discrimination by the sizes of PCR products. This amplified
two distinct DNA fragments of 913 and 649 bp in Williams 82 and Keburi, respectively. The practicality of the developed co-dominant
marker for Cgy-1 was also confirmed by amplification in five other soybean varieties including three wild types and two mutants. The heterozygosity
of the F1 plants at the Cgy-1 locus was ascertained using our novel co-dominant marker. This PCR-based co-dominant marker is capable of detecting the presence
or absence of β-conglycinin α′ subunit for soybean marker assisted breeding system. 相似文献
996.
997.
S R Tannenbaum D Fett V R Young P D Land W R Bruce 《Science (New York, N.Y.)》1978,200(4349):1487-1489
Studies of nitrate balance in humans and analyses of fecal and ileostomy samples indicate that nitrite and nitrate are formed de novo in the intestine, possibly by heterotrophic nitrification. These findings significantly alter our previous conceptions of human exposure to nitrite and suggest an even wider role for nitrite in the etiology of human cancer. 相似文献
998.
Young B 《Science (New York, N.Y.)》1966,151(3707):151
999.
1000.