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Mao  Jin-Jin  Tian  Shou-Fu  Zou  Li  Zhang  Tian-Tian  Yan  Xing-Jie 《Nonlinear dynamics》2019,95(4):3005-3017
Nonlinear Dynamics - We consider the simplified (3+1)-dimensional B-type Kadomtsev–Petviashvili equation. We use the binary Bell polynomial theory to construct a bilinear form of the...  相似文献   
103.
A series of porphyrin‐containing polyimide (PI) photocatalysts were synthesized by a one‐step solvothermal method. Characterization results revealed that porphyrin was uniformly coupled into the PI framework through covalent bonding and the visible‐light absorption was greatly improved. The photodegradation activity of porphyrin‐containing PIs for methyl orange (MO) under visible light was enhanced significantly, with the highest pseudo‐first‐order rate constant 35 times higher than that of neat porphyrin and 10 times higher than that of porphyrin‐free PI. The enhancement is mainly attributed to an increased light harvesting accompanied by a varied HOMO level, which was clarified by control experiments, characterizations and theoretical calculations. This work provides an insight into multiple effects of dye molecules in dye‐containing heterogeneous photocatalysts.  相似文献   
104.
Nanogels (NGs) are 3‐dimensional (3D) networks composed of hydrophilic or amphiphilic polymer chains, allowing for effective and homogeneous encapsulation of drugs, genes, or imaging agents for biomedical applications. Polyethylenimine (PEI), possessing abundant positively charged amine groups, is an ideal platform for the development of NGs. A variety of effective PEI‐based NGs have been designed and much effort has been devoted to study the relationship between the structure and function of the NGs. In particular, PEI‐based NGs can be prepared either using PEI as the major NG component or using PEI as a crosslinker. This review reports the recent progresses in the design of PEI‐based NGs for gene and drug delivery and for bioimaging applications with a target focus to tackle the diagnosis and therapy of cancer.  相似文献   
105.
We report the polymerization of phenyl isocyanides with the chiral palladium(II) initiating system. The resulting polymers with optically active properties were obtained by polymerization of the racemic isocyanide monomer(rac-1), and enantiomerically unbalanced polymerization of the monomer was found, providing substantial evidence for the enantiomer-selective polymerization of rac-1 mediated through chiral catalyst. A comparison between the enantiomerically pure monomers, 4-isocyanobenzoyl-L-alanine decyl ester(1 s) and 4-isocyanobenzoyl-D-alanine decyl ester(1 r), revealed a drastic discrepancy in the reactivity ratio of their homopolymerizations.It turned out that the monomer reactivity ratio of 1 s was higher than that of 1 r with chiral ligands. The results clearly demonstrated the inclination for incorporation of the 1 s enantiomer during the polymerization process and thus resulted in the enantiomer-selective polymerization in this system. The effects of the catalyst chirality on the optically active properties of polymerization were investigated,and it was concluded that the formation of higher-ordered conformation with a handed helicity might be attributed to the chiral induction of chiral palladium(II) catalyst. Moreover, the polymers obtained through the enantiomer-selective polymerization of the enantiomerically pure monomer were with a significant improvement of the optical activity if the chirality of the monomer and the catalyst matched with each other.  相似文献   
106.
Asymmetric Michael addition between 3-ethyl carboxylate substituted pyrazolones and 5-alkenylthiazolones catalyzed by a series of chiral bifunctional hydrogen bonding organocatalysts was investigated. Good yields (up to 96%) and excellent enantioselectivities (up to 99% ee) were achieved by using a squaramide containing piperidine group derived from (1S, 2S)-cyclohexanediamine. This strategy provides facile access to a diverse library of thiazole-pyrazolone derivatives with potential bioactivity.  相似文献   
107.
Sorption of iodine on Beishan granite was studied by batch method. Great difference exists in the sorption behaviors of I? and IO3?. Under acidic condition, the sorption of IO3? improves dramatically, and IO3? could partly convert to I?. However, the sorption of I? is close to zero at all studied pH. Humic acid can slight improve the sorption of IO3?, but greatly improve the sorption of I? in acidic condition. The postulated sorption mechanisms of IO3? are electrical interaction and followed by reduction.  相似文献   
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Eleven triazolyl substituted tetrahydrobenzofuran derivatives were synthesized in high yields as novel H+/K+‐ATPase inhibitor via one‐pot CuI‐catalyzed three‐component click reaction of azide, secondary amine and 3‐bromopropyne under mild conditions in water. Their structures were characterized by NMR, IR, ESI‐MS, elemental analysis and single‐crystal X‐ray diffraction analysis. Most of the target compounds exhibited better H+/K+‐ATPase inhibitory activity than commercial omeprazole with IC50 values less than 15 µmol·L?1. The initial structure‐activity analysis suggested that the triazole substituted by cycloalkyl, aromatic ring or O‐containing side‐chain seemed to be beneficial for enhancing the activity.  相似文献   
110.
正The Chang'E-3(CE-3)mission began with a smooth countdown and flawless launch on the Long March 3B rocket from the Xichang satellite launch center at 01:30 CST on December 2,2013.It landed on the northeastern Imbrium basin(340.49°E,44.12°N)at 21:11 CST on December 14,2013,and the Yutu rover was deployed from the lander the next morning at 04:35.The lander was equipped with a number of remote-sensing  相似文献   
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