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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
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EucalyPtusgl0bulusLabill.(Myrtaceae)isakindofmedicinalplantwidelydistributedintheYunnanpr0vinceofChina.ItSleaves,rootSandffoitShavebeenusedastraditionalremediesforthetreatmentofinfluenza,dysentery,enteritis,rheumatalgiaandbleeding.BesidesvolatileterpenoidconstituentSintheessential0iloftheleavesandfruits,theoccurrenceofanumber0fphloroglucinol-sesquiterpene-or-m0n0terpene-c0upledcomPoundsnamedmacrocarpals'andeugl0bals'intheleavesandbudshasbeenrepofted.Inordertostudythechendcalandbioactivecon… 相似文献
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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
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The novel applications of molybdenum disulfide in recent research were reviewed, such as in lubricant, catalyst and photoelectrochemical solar cells. Recently, we found that LiMoS2 is a good candidate for new anode materials for lithium ion batteries with high lithium storage capacity.Here, the anode material LiMoS2 was synthesized by a hydrothermal method at 150℃ and the electrochemical characterization as an anode material for lithium ion batteries was examined.put in Teflon-lined stainless steel autoclaves of capacity 40 mL. Distilled water was used to fill the autoclaves to 70 % of the total volume. The autoclaves were maintained at 150℃ for 24 h and then cooled naturally. The resulting dark-gray powders were filled and washed with distilled water,diluted hydrochloric acid and ethanol, successively. The final products were dried at 80℃ for 24 h.The powder X-ray diffraction pattern showed the prepared LiMoS2 was amorphous structure. A test cell using LiMoS2 as the active material was discharged and charged between 3 and 0.01 V with respect to Li metal at a constant current density of C/5 (that is, one lithium per formula unit in 5 hours). During the first discharge, the potential rapidly drops to reach a large plateau at 2.2 V, then slowly drops to the other plateau at 0.8 V, and then continuously decreases down to 0.01V. There is only a plateau at 1.35 V in the subsequent discharge curves. The plateaus of charge potential appear at about 1.9 V.The irreversible loss was 41% in the first cycle. The ratio of discharge and charge is more than 99%in the subsequent cycles. Moreover, the ratio of discharge and charge almost reaches 100% after thedemonstrated that LiMoS2 has a very high capacity and a good cycle-ability as an anode material forlithium ion batteries. 相似文献
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用(RCp)2MCl2和(RCp)TiCl3(R=H,Me;M=Ti,Zr)分别与具有生物活性的2-甲氧基-5-氟尿嘧啶、2-甲硫基-5-氟尿嘧啶在甲苯溶剂中110℃下反应,合成了20个未见报道的(RCp)·M(Opm)2Cl、(RCp)2M(OPm)Cl和(RCp)M(OPm)Cl2(OPm=2-甲氧基-5-氟尿嘧啶基,2-甲硫基-5-氟尿嘧啶基)型钛锆配合物,这些配合物均经元素分析、1HNMR、IR光谱鉴定.初步动物试验表明,配合物1、4、11、14对小白鼠移植性艾氏腹水场的抑制作用居首,而配合物2、3、5、6、12、13、15、16次之,其它锆配合物几乎没有抑制作用。 相似文献
10.
本文运用PM3算法计算得到氯酚(CPs)的分子结构参数,并结合光解速率进行PLS分析,建立了速率与量子化参数之间的关系模型,模型的Q2cum分别为0.8776和0.9545(>0.5),具有良好的预测能力。研究结果表明,参数Ehomo、Elumo Ehomo、Elumo、N、Mw、Elumo-Ehomo、(Elumo-Ehomo)2是决定CPs光解速率的主要因素;CPs的光解速率随Ehomo、Elumo Ehomo、Elumo、Elumo-Ehomo、(Elumo-Ehomo)2的增大而增大,随N、Mw的增大而减小。 相似文献