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There are eleven species of Satyrium hitherto reported in China, among which, after a detailed examination of herbarium specimens consisting of about 300 plants, only four forms, represented by S. nepalense D. Don, S. ciliatum Ldl., S. setchuenicum Kranzl. and S. yunnanense Rolfe, are susceptible of division. S. nepalense is a wides- pread species with its main distribution centre in indian region, whereas the other three, with which the present paper deals, are largely distributed in our country.       S. ciliatum is characterized by its pink flowers with spurs about half as long as the ovary.  It is usually found in mountain meadows at an altitude between 1900- 4100m. from Szechuan through Kweichow, Yunnan  and  Tibet,  southwestward  to Sikkim and Bhutan. In all its flowers examined, both female and male organs are perfect and many have produced capsules. It is, no doubt, the hermaphrodite form as seen in the ordinary orchids.       S. setchuenicum closely resembles S. ciliatum in habit, distinguished mainly by having flowers without or with short spurs.  These two forms are sympatric.  In our herbarium, for instance, they are sometimes found on a same specimen or the different sheets with the same field number, such as Y. Tsiang 11454, R. C. Ching 24184, T. P. Wang 9497, etc.  A detailed comparison shows that in S. setchuenicum the anther and pollinia are abortive or even entirely absent, and the stigma is larger than  the rostellum which usually partly thickens and becomes some-what stigma-like, while in S. ciliatum the male organ is well developed, and the thin rostellum is larger. Between these two forms several intermediates are found. It is quite certain that they are dif- ferent sexual forms belonging to one and the same species, and so called S. setchuenic- um is but a female form of S. ciliatum.      Another sympatric form is S. yunnanense, characterized by its yellow flowers with somewhat horizontally extended spurs.  Its anther, pollinia and rostellum are very similar to those of hermaphrodite form of S. ciliatum, but the ovary is narrower and the stigma is usually smaller.  It is interesting to note that in all specimens examined consisting of 36 individuals, no fruit can be found, while in those of S. ciliatum, includ- ing both female and hermaphrodite forms, the lower flowers of the racemes are mostly found to have produced fine seed-capsules. From  these  facts we  may confidently regard this species as the male form of S. ciliatum.      Thus, we have three separate sexual forms in S. ciliatum, to which eight specific names previously recorded in China are here referred. Detailed discussion and descrip- tion as well as a key to the chinese species are given as above. Its geographical distribu- tion is mapped.  The flowers of these three forms are illustrated.  All the specimens cited here, with a few exceptions, are deposited in the herbarium of Institute of Botany,Academia Siaica.  相似文献   

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Nitrogen-vacancy (NV) centers in diamond are promising quantum sensors because of their long spin coherence time under ambient conditions. However, their spin resonances are relatively insensitive to non-magnetic parameters such as temperature. A magnetic-nanoparticle-nanodiamond hybrid thermometer, where the temperature change is converted to the magnetic field variation near the Curie temperature, were demonstrated to have enhanced temperature sensitivity () (Wang N, Liu G-Q and Leong W-H et al. Phys Rev X 2018; 8: 011042), but the sensitivity was limited by the large spectral broadening of ensemble spins in nanodiamonds. To overcome this limitation, here we show an improved design of a hybrid nanothermometer using a single NV center in a diamond nanopillar coupled with a single magnetic nanoparticle of copper-nickel alloy, and demonstrate a temperature sensitivity of . This hybrid design enables detection of 2 mK temperature changes with temporal resolution of 5 ms. The ultra-sensitive nanothermometer offers a new tool to investigate thermal processes in nanoscale systems.  相似文献   

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