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991.
Sung-Chieh Chao Yu-Chan Yen Yen-Fang Song Yi-Ming Chen Hung-Chun Wu Nae-Lih Wu 《Electrochemistry communications》2010,12(2):234-237
The interior microstructures of Sn particles developed during electrochemical lithiation/de-lithiation have been revealed by in situ X-ray transmission microscopy (TXM). The Li-alloying particles exhibited the formation of core–shell internal structure along with crack formation within the lithiated zone during the first lithiation. The extent and speed of the expansion process was shown to be a strong function of particle size. Upon completion of the first de-lithiaiton, the particles only partially (~10%) contracted, while re-crystallization of Sn continued to take place within the interior of the particles during a following idle period. The re-crystallization process alleviated the pulverization problem and led to the formation of porous Sn particles, which exhibited remarkably attenuated dimensional variations during subsequent cycles. 相似文献
992.
Jiu Lin Zhaoyin Wen Xiuyan Wang Shufeng Song Yu Liu 《Journal of Solid State Electrochemistry》2010,14(10):1821-1827
Na-β/β″-alumina powders were synthesized by a mechanochemical processing. The influences of mechanical activation in the phase composition and microstructure of the final powders were investigated. Fine Na-β/β″-alumina powders were obtained at a lower temperature than that of a conventional solid-state reaction processing. The mechanism of the mechanical activation was studied. It was found that mechanical activation greatly affected the calcining process and phase composition of the precursory powders. 相似文献
993.
994.
Shupeng Liu Ye Sun Heng Chen Suxian Song Yuhong Xu 《Applied biochemistry and biotechnology》2010,162(4):1206-1213
Salvianolic acid B is one of the effective components from the Chinese traditional drug Salvia miltiorrhiza (Danshen), which is widely used as a usual clinic drug for atherosclerosis-related disorder patients in China. But the targeting protein of salvianolic acid B is still not known. The possible targeting proteins of salvianolic acid B were explored by high throughput screening in this paper. Attached to the magnetic nanoparticles, salvianolic acid B was used for screening the high-affinity protein from the displaying cDNA peptide library phage. After biopanning, the selected protein or peptide sequences were used to explore the whole proteins containing the selected sequences in the National Center for Biotechnology Information website using blast. One of the selected phages was carried out by affinity analysis with salvianolic acid B using capillary electrophoresis (CE). The CE results indicated that the protein or peptide on the surface of the selected phages could bind the drug salvianolic acid B. The results are helpful to preliminarily explain the pharmacology of salvianolic acid B. 相似文献
995.
Sannian Song Zhitang Song Bo Liu Liangcai Wu Songlin Feng 《Applied Physics A: Materials Science & Processing》2010,99(4):767-770
The phase-change characteristics of Ge2Sb2Te5 (GST) films for phase-change random access memory (PCM) devices were improved by incorporating HfO2 into GST film using cosputtering at room temperature. Phase separation (GST-rich nanocrystals were surrounded by HfO2-rich amorphous phase) has been observed in annealed GST-HfO2 composite films and the segregated domains exhibited a relatively uniform size. The reduced reset voltage of GST-HfO2 based cell was due to the reduced programming volume by incorporating HfO2 into GST. This work clearly reveals the highly promising potential of GST-HfO2 composite films for application in PCM. 相似文献
996.
从理论和实验上研究了红绿荧光强度反转现象。实验测量发现Er(0.5)Yb(9.5)∶FOV纳米相氟氧化物玻璃陶瓷存在强的红绿荧光强度反转现象,实验测量得到其红绿荧光强度反转动态范围为877,同时计算了Er(0.5)Yb(9.5)∶FOV的所有基础光谱参量,建立了对系统所有稀土离子能级的动力学过程进行数值模拟计算的理论基础。 相似文献
997.
Three ion-pair complexes, [RbzPy](+)[Ni(mnt)(2)](-) (mnt(2)(-) = maleonitriledithiolate; [RbzPy](+) = 4-R-benzylpyridinium; R = Br (1), Cl (2), and NO(2) (3)), with unusual magnetic properties have been synthesized and characterized. The crystal structures of 1 and 2 have been solved. The two complexes belong to the P2(1)/c space group with Z = 4 and C(20)H(11)BrN(5)NiS(4), a = 12.0744(17) A, b = 26.369(4) A, c = 7.440(3) A, and beta = 102.63(3) degrees for 1 and C(20)H(11)ClN(5)NiS(4), a = 12.105(2) A, b = 26.218(4) A, c = 7.374(2) A, and beta = 102.55(2) degrees for 2, respectively. The [Ni(mnt)(2)](-) anions in 1-3 form uniformly spaced one-dimensional (1-D) magnetic chains of s = 1/2 at room temperature. The temperature dependences of the susceptibility for 1-3 show that they undergo phase transitions. All three complexes are paramagnetic in their high-temperature (abbreviation HT) phase and diamagnetic in the low-temperature (abbreviation LT) phase because of strong dimerization along the stacking direction. The results of thermal analysis (DSC) further confirm that the phase transition for 1 and 2 is first-order but maybe second-order for 3. The phenomena observed in this study are similar to those of the 1-D radical systems. 相似文献
998.
The Li4+xMxSi4+xO4‐yLi2O (M=Al, B; x = 0 to 0.6, y = 0 to 0.5) ion conductors were prepared by the Sol‐Gel method and examined in detail. The powder and sintered samples were characterized by DTA‐TG, XRD, SEM, and AC impedance techniques. The experimental results show that the conductivity and sinterability in creased with the amount of excess lithium oxide in the silicate. The Li2O phase acts as a flux to accelerate the sintering process and to obtain high conductivity of grain boundaries. The particle size of the sintered pellets is about 0.25 μm. The maximum conductivity at 200 °C is 5.40 × 10?3s cm?1 for Li4.4Al0.4 Si0.6O4‐0.3Li2O. 相似文献
999.
1000.
Hanna Fabczak PhunBum Park Stanislaw Fabczak Pill-Soon Song 《Photochemistry and photobiology》1993,57(4):702-706
Abstract— The heterotrichous ciliate, Stentor coerulus , exhibits a welll defines photophobic response to a sudden increase in the intensity of visible light. the phobic reactions usually appear with a latency perios (i.e. a time delay between the onset of the stimulus and the stop response). This latency of phobic response was significatly increased when the cells werw incubated with 8-bromo-guanosine3',5'-cyclic monophospjhate. In the presence of this nucleotide, a reduction of cell responsiveness (i.e. the number of photophobically responding cells) was also observed. similar effects were observed when cells were treated with pertussis toxin, a G-protein activity modulator, and 3'-isobutyl-methylxanthine, an inhibitor of guanosine 3', 5'-cyclic monophosphate (cGMP) phosphodiesterase. the G-protein activator fluoroaluminate and 6-anilino-5,8-quinolinedione (LY 83583) (an effective agent for lowerin cellular cGMP levels) showed opposite effects on hte cell photophobic response. These result indirectly suggesnt that the level of cytoplamic cGMP, possibly modulated by a G-protein-coupled CGMP phosphodiesterase, plays a phototreasducing role in Stentor . In addition, using an antiserum raised against bovine transducin, a cross reacting protein with an apparent molecular mass of 39 kDa was detected on immunoblots. The α-subunits of a Stentor G-protein has also been partially cloned and sequenced. However, the possible coupling between the G-protein and the putative phosphodiesterase remains to be established. 相似文献