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991.
992.
Jin Wang HongLei Zhan LiPing He Kun Zhao HuiBin Lü KuiJuan Jin GuoZhen Yang 《中国科学:物理学 力学 天文学(英文版)》2016,59(11):114221
正Dear Editors,The evaluation of the oil-gas resources’potential depends on the characterization of reservoirs.The geometry of the pore-crack structures and the compositions of the pore walls have influence on hydrocarbon production about capillarity and permeability[1].Besides,it has been known that the adsorption phenomenon in micro-structure plays a significant role in oil-gas reservoirs.Some techniques have been applied to characterize conventional and unconventional reservoirs, 相似文献
993.
Li Xuetian Shao Zhongbao Liu Kuiren Zhao Qing Liu Guangfu Xu Binshi 《Journal of Solid State Electrochemistry》2018,22(9):2837-2843
Journal of Solid State Electrochemistry - LiFePO4-x/3Fx/C (x = 0, 0.03, 0.06, 0.09) were obtained via wet mechanical agitation-assisted high-temperature ball milling method. XRD, SEM,... 相似文献
994.
995.
在几类群上讨论了三阶柯西差分方程解的存在性问题,将二阶柯西差分方程的已有结论进一步推广到三阶的情况,并给出在不同群上的一般解. 相似文献
996.
Yue Zhang Wenhao Liu Jin Si Xiyu Zhu Chengping He Haonan Zhao Hai-Hu Wen 《中国科学:物理学 力学 天文学(英文版)》2018,(9)
Superconductivity is observed in a new nontoxic cuprate system Ga-Ba-Ca-Cu-O,with T_c=82 K for Ga Ba_2Ca_5Cu_6O_(14+δ)(Ga-1256)and T_c=116 K probably for Ga Ba_2Ca_3Cu_4O_(10+δ)(Ga-1234)or Ga Ba_2Ca_2Cu_3O_(8+δ)(Ga-1223),respectively.All compounds are fabricated by solid state reaction method under high pressure and high temperature.Samples are characterized by resistivity,magnetization and X-ray diffraction(XRD)measurements.The temperature dependence of magnetization measured in both zero-field-cooled and field-cooled processes on one sample(S1)shows two superconducting transitions at about 82 K and113 K.The estimated shielding fraction for the phase with T_cof 82 K is about 67%,while the fraction for another phase with T_(c )of 113 K is quite small.The XRD Rietveld refinement for S1 indicates two main phases existing in the sample,Ga-1256 with fraction of about 58%and non-superconducting Ca_(0.85)Cu O_2with fraction of about 42%respectively.Thus,we can conclude the superconducting phase with transition temperature of 82 K is due to Ga-1256.The resistivity measurement also confirms the superconductivity for S1,and the resistivity reaches zero at about 82 K.The temperature dependence of magnetization for another sample(S2)shows much higher superconducting shielding fraction for the phase with T_cof 116 K,which may be a promising prospective for the synthesis of Ga-1234 or Ga-1223 phase. 相似文献
997.
Quantum dots (QDs) have shown great potential to provide spatial, temporal, and structural information for biological systems. However, blinking, photobleaching, and spectral blueshift are adverse effects on their practical applications in biomedical research. An investigation of the effects of six reducing agents including cysteine (Cys), 1,4‐dithiothreitol (DTT), ethyl gallate (EG), L ‐glutathione (GSH), mercaptoacetic acid (MAA), and thiourea (TU) on the photostability of single QDs was studied. Our experiments demonstrate that both DTT and EG effectively inhibit blinking, photobleaching, and spectral blueshift. GSH molecules block blinking and photobleaching of QDs. The other reagents, Cys, MAA, and TU, only have the ability to counteract blinking. Possible explanations are given on the basis of research evidence. The results suggest possibilities for significant improvements in QDs for biological applications by adjusting the environmental conditions. 相似文献
998.
A unique ultrafine full-vulcanized powdered ethyl acrylate rubber (EA-UFPR) was used as the toughening modifier for poly (lactic acid) (PLA). Largely improved tensile toughness was successfully achieved with the incorporation of only 1 wt% EA-UFPR, while the tensile strength and modulus of the blends were almost the same as pure PLA. The highly efficient toughening of PLA by UFPR is mainly ascribed to the strong interfacial interaction between PLA and UFPR and good dispersion of UFPR particles in PLA matrix. Our work provides an effective toughening method to largely improve the mechanical properties of PLA without sacrificing its stiffness, which is very important for the wide application of PLA materials. 相似文献
999.
Suppression of the Charge Density Wave State in Two-Dimensional 1T-TiSe2 by Atmospheric Oxidation
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Lifei Sun Chuanhui Chen Dr. Qinghua Zhang Christian Sohrt Tianqi Zhao Dr. Guanchen Xu Jinghui Wang Prof. Dong Wang Prof. Kai Rossnagel Prof. Lin Gu Prof. Chenggang Tao Prof. Liying Jiao 《Angewandte Chemie (International ed. in English)》2017,56(31):8981-8985
Two-dimensional (2D) metallic transition-metal dichalcogenides (TMDCs), such as 1T-TiSe2, have recently emerged as unique platforms for exploring their exciting properties of superconductivity and the charge density wave (CDW). 2D 1T-TiSe2 undergoes rapid oxidation under ambient conditions, significantly affecting its CDW phase-transition behavior. We comprehensively investigate the oxidation process of 2D TiSe2 by tracking the evolution of the chemical composition and atomic structure with various microscopic and spectroscopic techniques and reveal its unique selenium-assisting oxidation mechanism. Our findings facilitate a better understanding of the chemistry of ultrathin TMDCs crystals, introduce an effective method to passivate their surfaces with capping layers, and thus open a way to further explore the functionality of these materials toward devices. 相似文献
1000.
Z. H. Zhou Q. F. Yi L. H. Liu Y. M. Zhao X. P. Liu J. N. Zhou 《Journal of Macromolecular Science: Physics》2013,52(5):940-952
In vitro degradation experiments of poly-L-lactic acid (PLLA) and bovine bone (BB) composites were carried out in a phosphate-buffered solution (PBS) at 37°C with a pH of 7.4. The influence of BB content on pH value of PBS, water uptake, molecular weights, molecular weight distributions, weight losses, mechanical strengths, and morphologies of PLLA/BB was investigated with degradation times. The results indicated that the presence of the BB modified the degradation of the PLLA matrix. The degradation rate of PLLA in the PLLA/BB composite was slower than the degradation rate of the sole PLLA material. Furthermore, the degradation rate of the composites became slower with the increasing content of BB in PLLA/BB composites. 相似文献