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121.
Qingbing Xia Zeheng Lin Weihong Lai Yongfei Wang Cheng Ma Zichao Yan Qinfen Gu Weifeng Wei Jia‐Zhao Wang Zhiqiang Zhang Hua Kun Liu Shi Xue Dou Shu‐Lei Chou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(40):14263-14266
Two‐dimensional (2D) superlattices offer promising technological opportunities in tuning the intercalation chemistry of metal ions. Now, well‐ordered 2D superlattices of monolayer titania and carbon with tunable interlayer‐spacing are synthesized by a molecularly mediated thermally induced approach. The 2D superlattices are vertically encapsulated in hollow carbon nanospheres, which are embedded with TiO2 quantum dots, forming a 0D‐2D‐3D multi‐dimensional architecture. The multi‐dimensional architecture with the 2D superlattices encapsulated inside exhibits a near zero‐strain characteristic and enriched electrochemical reactivity, achieving a highly efficient Na+ storage performance with exceptional rate capability and superior long‐term cyclability. 相似文献
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Zhaoming Liu Pei Qiu Jing Li Guangying Chen Yan Chen Hongju Liu Zhigang She 《Tetrahedron》2018,74(7):746-751
A pair of novel 2,3-diaryl indone derivatives (+)- and (?)-ascomindone D [(+)-1 and (?)-1, respectively], as well as two new prenylated polyketides ascomfurans C (2) and ascomarugosin A (3) were obtained from the culture of a mangrove endophytic fungus Ascomycota sp. SK2YWS-L together with three known compounds (4–6). The enantiomers (+)-1 and (?)-1 were purified through chiral HPLC separation, which represented the first example of resolving 2,3-diaryl indone atropisomers in natural products. The structures of the new compounds were determined on the basis of interpretation of spectroscopic data including X-ray diffractions and the absolute configurations of (+)-1 and (?)-1 were elucidated by ECD calculations. The biosynthesis pathway was proposed. In the anti-inflammatory assay, (+)-1 and (?)-1 exhibited potential anti-inflammatory effects by inhibiting against the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW 246.7 mouse macrophages with the IC50 values of 17.0 and 17.1 μM, respectively. 相似文献
127.
Li‐Ping Cao Xiang‐Gao Meng Meng Gao Neng‐Fang She An‐Xin Wu 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(2):o69-o72
Two new glycoluril derivatives, namely diethyl 6‐ethyl‐1,4‐dioxo‐1,2,2a,3,4,6,7,7b‐octahydro‐5H‐2,3,4a,6,7a‐pentaazacyclopenta[cd]indene‐2a,7b‐dicarboxylate, C14H21N5O6, (I), and 6‐ethyl‐2a,7b‐diphenyl‐1,2,2a,3,4,6,7,7b‐octahydro‐5H‐2,3,4a,6,7a‐pentaazacyclopenta[cd]indene‐1,4‐dione, C20H21N5O2, (II), both bearing two free syn‐urea NH groups and two ureidyl C=O groups, assemble the same one‐dimensional chains in the solid state running parallel to the [010] direction via N—H...O hydrogen bonds. Furthermore, the chains of (I) are linked together into two‐dimensional networks via C—H...O hydrogen bonds. 相似文献
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She NF Meng XG Gao M Wu AX Isaacs L 《Chemical communications (Cambridge, England)》2008,(27):3133-3135
Glycoluril derivative--whose bulky Ph-C[triple bond]C- substituents prevent formation of H-bonded tapes--undergoes solvent dependent assembly in the crystal; a tetrameric molecular bowl is formed by R(24) H-bonding interactions from CH(2)Cl(2) whereas DMF results in H-bond dimerization followed by oligomerization via C-H...pi interactions. 相似文献
129.
Dong‐E Wang Feng Wang Xiang‐Gao Meng Yu Ding Li‐Li Wen Dr. Dong‐Feng Li Prof. Dr. She‐Ming Lan 《无机化学与普通化学杂志》2008,634(14):2643-2648
Three inorganic‐organic hybrid frameworks [Mn(HIMDC)(4,4′‐bipyo)0.5(H2O)]n (1) , [Cd(H2IMDC)2(2,2′‐bipyo)] (2) and [Ca(HIMDC)(H2O)2·H2O]n (3) (H3IMDC = 4,5‐imidazoledicarboxylate; 4,4′‐bipyo = 4,4′‐bipyridine‐N,N′‐dioxide; 2,2′‐bipyo= 2,2′‐bipyridine‐N,N′‐dioxide) have been hydrothermally synthesized and characterized by the elemental analyses, IR spectra, TG analysis and the single crystal diffraction. Both compounds 1 and 3 exhibit 2D layers while 2 is a monomer. It is noteworthy that compound 2 exhibits strong fluorescent emission in the solid state at room temperature. 相似文献
130.
Degradation behaviors of porous scaffolds play an important role in the engineering process of a new tissue. In this study, three-dimensional porous silk fibroin/chitosan (SFCS) scaffolds were successfully prepared by freeze-drying method. In vitro degradation behaviors of SFCS scaffolds have been systematically investigated up to 8 weeks in phosphate buffer saline (PBS) solution at 37 °C. The following properties of the scaffolds were measured as a function of degradation time: pore morphology, structure, weight loss, and wet/dry weight value. The pH value of the PBS solution during degradation was also detected. SFCS scaffolds maintained its porous structure till 6 weeks of degradation. During the first 2 weeks, the pH value fluctuated in a narrow range from 6.53 to 6.93. SFCS scaffolds degraded much more quickly during the first 2 weeks, and the weight loss reached 19.28 wt% after 8 weeks of degradation. The degradation process affects little SFCS scaffolds' swelling properties. 相似文献