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1.
The solid-liquid interface motion of NaBi(WO4)2 (NBWO) melt crystal growth is observed in an in situ system, in which the whole processes of interface transition from fiat interface and cellular to dendrite are visualized. The spacing of the dendrite under smaller temperature gradient turns out to be larger than that under larger temperature gradient, which is found to be sensitive to the temperature distribution. The mechanism of dendrite growth of NBWO is studied based on the model of the growth units of anion coordination polyhedra. The { 001} face has two apex links, so it shows higher stability and has high growth rate and forms the arm of dendrite, whereas the {010} face has only one apex link, and thus shows relative slower growth rate and firstly forms the branches. 相似文献
2.
In Situ Observation of Skeletal Shape Transition during BaB2O4 Crystal Growth in High-Temperature Solution
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The transition from a fiat solid-liquid interface to a skeletal shape during BaB2O4 (BBO) single crystal growth in Li2B4O7 flux is observed in real time by an optical high-temperature in-situ observation system. The movement of crystal step is also investigated. The observation results demonstrate that the steps propagate along and parallel to the fiat interface when the crystal size is small. Nevertheless, they will ‘bend' close to the face centre if the crystal size becomes greater. Atomic force microscopy reveals that more deposition places near the face centre give rise to the bending of advancing steps and thus the formation of a vicinal interface structure. Measurements of step velocity show that the velocity keeps nearly constant at different moments for one specific step, whereas the step on a newly formed layer advanced faster than that on a previously formed one when the crystal size is larger than 210μm or so. Thus interracial morphological instability occurs and a skeletal interface is obtained. 相似文献
3.
EucalyPtusgl0bulusLabill.(Myrtaceae)isakindofmedicinalplantwidelydistributedintheYunnanpr0vinceofChina.ItSleaves,rootSandffoitShavebeenusedastraditionalremediesforthetreatmentofinfluenza,dysentery,enteritis,rheumatalgiaandbleeding.BesidesvolatileterpenoidconstituentSintheessential0iloftheleavesandfruits,theoccurrenceofanumber0fphloroglucinol-sesquiterpene-or-m0n0terpene-c0upledcomPoundsnamedmacrocarpals'andeugl0bals'intheleavesandbudshasbeenrepofted.Inordertostudythechendcalandbioactivecon… 相似文献
4.
G. A. Kliger L. S. Glebov A. N. Shuikin V. P. Ryzhikov A. I. Mikaya V. G. Zaikin S. M. Loktev 《Russian Chemical Bulletin》1990,39(2):431-431
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 493–494, February, 1990. 相似文献
5.
L. S. Glebov A. N. Shuikin A. I. Mikaya V. G. Zaikin A. E. Yatsenko G. A. Kliger S. M. Loktev 《Russian Chemical Bulletin》1988,37(7):1513-1513
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp, 1695–1696, July, 1988. 相似文献
6.
A. I. Mikaya V. I. Smetanin V. G. Zaikin A. V. Antonova N. S. Prostakov 《Journal of mass spectrometry : JMS》1983,18(3):99-104
A method for structure determination of aliphatic alcohols within mixtures is described. It involves the use of a vapour phase dehydrogenation micro-reactor (Cu, 300°C) located between the chromatographic column and the mass spectrometer or between the injection port and the column. Since primary and secondary alcohols are converted into corresponding carbonyl compounds, they can be readily differentiated from tertiary alcohols and dialkyl ethers. An examination of the mass spectra of alcohols and carbonyl compounds permits the determination of molecular mass, the location of hydroxyl group and the determination of branching at the β-carbon atom. 相似文献
7.
8.
血橙中微量元素的测定 总被引:2,自引:0,他引:2
采用电感耦合等离子体原子发射光谱仪(ICP-AES),对血橙果肉汁、皮、籽中10种微量元素进行了测定。结果表明,血橙果肉汁、皮、籽中含有Ca、Mg、Fe、Zn、Mn、Cu、Ni等丰富的人体必需微量元素,且血橙果皮、籽中的微量元素含量普遍高于果肉汁中的微量元素的含量,这为血橙药效功能的进一步研究和资源综合开发利用提供一定的科学依据。 相似文献
9.
10.
E. A. Chernyshev O. V. Kuz'min A. V. Lebedev V. G. Zaikin A. I. Mikaya 《Russian Chemical Bulletin》1986,35(4):821-824
Conclusions The main products of the pyrolysis of 8,8-dimethyl-8-sila-2,3,4,5-tetrathiabicycIo-[4.3.0]nonane at 400 are 1,1-dimethylsilacyclopent-3-ene and 1,1-dimethyl-1-sila-2-thiacyclo-hexa-3, 5-diene, and at 600 carbon disulfide and thiophene; silacyclopentene is the sole reaction product, characteristic for the mass-spectrometric decomposition of the initial tetrasulfide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No, 4, pp. 902–905, April, 1986. 相似文献