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991.
992.
Four new flavonoids were isolated from Campylotropis hirtella and these are a chromone and a 2H-chromene, an isoflavone and an isoflavanonol. The structures of these compounds were elucidated by extensive spectroscopic measurements. All of the compounds were assessed for immunosuppressive activity. Compound 4 showed very strong T lymphocyte suppression activity (IC50: 0.13 μM) and potent B lymphocyte suppression activity (IC50: 0.26 μM). Due to its potent immunosuppressive activity and lower cytotoxicity, further structure–activity studies will be pursued on this compound. 相似文献
993.
This account provides an overview of current research activities that focus on the synthesis and applications of nanomaterials from noble metal (e.g., Au, Ag, Pd) and iron oxide (Fe3O4) hybrids. An introduction to the synthetic strategies that have been developed for generating M–Fe3O4 nanomaterials with different novel structures is presented. Surface functionalization and bioconjugation of these hybrid nanoparticles and nanocomposites are also reviewed. The utilization of the advantageous properties of both noble metals and iron oxide for a variety of applications, such as theranostics, gene delivery, biosensing, cell sorting, bioseparation, and catalysis, is discussed and highlighted. Finally, future trends and perspectives of these sophisticated nanocomposites are outlined. The fundamental requirements underpinning the effective preparation of M–FexOy hybrid nanomaterials shed light on the future development of heterogeneous catalysts, nanotheranostics, nanomedicines, and other chemical technologies. 相似文献
994.
Mono-alkyl-functionalized pillar[5] arenes P1,P2,and P3 were synthesized by click reaction,which exhibited different self-assembly behavior in polar solvent DMSO.Stable pseudo [1] rotaxane was formed by the self-complexation from P1 or P2,whereas,concentration-dependent pseudorotaxane structures were generated by P3 which bearing more flexible side chain.Interestingly,the obtained pseudo[1] rotaxanes exhibited a dynamic fast assembly process upon adding NaBF4,resulting in the formation of Na+-induced pseudorotaxanes. 相似文献
995.
Nguyen Buong Vu Xuan Quynh Nguyen Thi Thu Thuy 《Journal of Fixed Point Theory and Applications》2016,18(3):519-532
In this paper, in order to solve a variational inequality problem over the fixed point set of a nonexpansive mapping on uniformly smooth or reflexive and strictly convex Banach spaces with a uniformly Gâteaux differentiable norm, we investigate an explicit iteration method, based on the steepest-descent and Krasnosel’skii–Mann algorithms. We also show that some modifications of the last and Halpern-type algorithms are special cases of our result. 相似文献
996.
997.
添加碱土金属对负载型铂锡催化剂长链烷烃脱氢反应性能的影响 总被引:1,自引:0,他引:1
用微型催化反应装置结合吡啶吸附 红外光谱、热重、氢化学吸附和程序升温等还原手段,研究了添加碱土金属离子助剂对负载型PtSn/γ-Al2O3催化剂长链烷烃(C10~13)脱氢反应性能的影响。结果表明,碱土金属助剂的引入可以降低催化剂积炭量、提高催化剂铂金属表面裸露度,从而提高催化剂脱氢反应稳定性。但强碱性的碱土金属助剂如Ba2+的引入增强了锡与载体之间的相互作用,减弱了锡与铂之间的相互作用, 导致反应后催化剂铂金属表面裸露度下降,故PtSnBa/γ-Al2O3催化剂脱氢活性较低。 相似文献
998.
Guan-jun Chang~ 《高分子科学》2008,(1):55-61
Di(4-bromophenyl)ketone and various aromatic diamines as the monomers,a series of novel poly(imino ketone)s (PIKs)have been synthesized via palladium-catalyzed aryl amination,which is Hartwig-Buchwald polycondensation reaction.The structures of PIKs are characterized by means of elemental analysis,FT-IR,~1H-NMR and UV-Vis spectroscopy. The results show a good agreement with the proposed structure.The general properties of PIKs are studied by DSC,TG and wide-angle X-ray diffraction,the solubility behavior... 相似文献
999.
CaO solubility in equimolar molten salts CaCl2–x (x = 0, NaCl, KCl, SrCl2, BaCl2 and LiCl) was determined at 873–1223 K and activity coefficient calculated. CaO solubility in the binary salts is less than in CaCl2, and the activity coefficient is greater than one. With increasing temperature CaO solubility increases and the activity coefficient decreases. The dependency of CaO activity coefficient on temperature in equimolar molten salts CaCl2–x is
相似文献
CaCl2 | RTln γCaO = 6961 + 5.06 T (K) | 1123–1223 K |
CaCl2–NaCl | RTln γCaO = 3985 + 17.67 T (K) | 923–1123 K |
CaCl2–KCl | RTln γCaO = 2384 + 22.72 T (K) | 1073–1223 K |
CaCl2–SrCl2 | RTln γCaO = 27245–1.13 T (K) | 1073–1223 K |
CaCl2–BaCl2 | RTln γCaO = 17068 + 10.19 T (K) | 1223–1273 K |
CaCl2–LiCl | RTln γCaO = 14724 + 0.72 T (K) | 923–1073 K |
Full-size table
1000.