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排序方式: 共有997条查询结果,搜索用时 240 毫秒
91.
92.
Generation of nanostructures containing from several to thousands of inorganic nanorods (NRs) organized in a highly ordered manner paves the way for applications that exploit directional properties of NR arrays. Self-assembly of NRs provides a simple and cost-efficient strategy for producing NR ensembles. This tutorial review highlights recent advances in the field of NR synthesis, summarizes the types of ligands used for NR synthesis and stabilization, reviews experimental and theoretical work on NR self-assembly that is driven by interactions between the ligands and describes current properties and applications of self-assembled NR structures. 相似文献
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94.
Rukhadze M Dzidziguri D Giorgobiani N Kerkenjia S 《Biomedical chromatography : BMC》2011,25(12):1364-1368
The structure of biomembranes was imitated by introducing nonionic surfactant polyoxyethylene (23) dodecylether, cholic acid and endogenic thermostable protein complex (14–65 kDa) into the mobile phase. The influence of concentration of these additives on the retention of the model compounds was studied. The competing interaction of cholic acid and endogenic thermostable protein complex in the lipid bilayer model was revealed on the basis of chromatographic data. The values of efficiency of the chromatographic column regarding solutes were increased by addition of endogenic thermostable protein complex to the mobile phase containing Brij‐35 and cholic acid. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
95.
A new ion-exchange adsorbent (IEA) derived from Fe(3)O(4)/SiO(2)-GPTMS-DEAE with paramagnetic properties was prepared. Fe(3)O(4) nanoparticles were firstly prepared in water-in-oil microemulsion. The magnetic Fe(3)O(4) particles were modified in situ by hydrolysis and condensation reactions with tetraethoxysilane (TEOS) to form the core-shell Fe(3)O(4)/SiO(2). The modified particles were further treated by 3-glycidoxypropyltrimethoxysilane (GPTMS) to form Fe(3)O(4)/SiO(2)-GPTMS nanoparticles. Fe(3)O(4)/SiO(2)-GPTMS-DEAE nanoparticles (IEA) were finally obtained through the condensation reaction between the Cl of diethylaminoethyl chloride-HCl (DEAE) and the epoxy groups of GPTMS in the Fe(3)O(4)/SiO(2)-GPTMS. The obtained IEA has features of paramagnetic and ion exchange properties because of the Fe(3)O(4) nanoparticles and protonated organic amine in the sample. The intermediates and final product obtained in the synthesis process were characterized. The separation result of genomic DNA from blood indicated that Fe(3)O(4)/SiO(2)-GPTMS-DEAE nanoparticles have outstanding advantages in operation, selectivity, and capacity. 相似文献
96.
Inoue Y Hasegawa N Tozuka Y Yonemochi E Oguchi T Higashi K Moribe K Yamamoto K 《Chemical & pharmaceutical bulletin》2011,59(10):1299-1302
Changes in molecular states of p-dimethylaminobenzonitrile (DMABN) coground with β-cyclodextrin (β-CD) were examined using solid-state fluorescence measurements. Formation of a DMABN/β-CD inclusion complex by coprecipitation was confirmed by powder X-ray diffraction measurement. The powder X-ray diffraction pattern of the ground mixture was a halo pattern and differed from the pattern of the mixture prepared by coprecipitation. Solid-state fluorescence measurements revealed emission by DMABN crystals in a twisted intermolecular charge-transfer state at 473 nm. DMABN in the DMABN/β-CD coprecipitate had a fluorescence emission peak at 393 nm due to its planar structure. In contrast, DMABN in a DMABN/β-CD ground mixture had an emission peak at 473 nm due to its twisted structure. Grinding time-dependent structural changes in DMABN were evaluated using fluorescence lifetime and relative quantum yield measurements. Structural changes in DMABN in the DMABN/β-CD coprecipitate from a planar to a twisted structure were observed with grinding. DMABN, dispersed in microcrystalline cellulose (CC) molecules in a DMABN/CC ground mixture, had a fluorescence emission peak at 473 nm. However, the excitation spectrum of a DMABN/β-CD ground mixture differed from that of DMABN in CC. These results indicated that the molecular state of DMABN accommodated in the β-CD cavity differs between the coprecipitate and the ground mixture. 相似文献
97.
Bromine reacts with the 1,2-bisadduct C(60)(OOtBu)(2) efficiently to form the cyclopentadienyl-type compound 4 (C(60)(OOtBu)(2)Br(4)). In the presence of AgClO(4), the four bromine atoms can be replaced regioselectively by methoxyl groups in a stepwise fashion to form C(60)(OOtBu)(2)Br(4-x)(OMe)(x). A second alcohol may be introduced by treating partially methoxylated compound 6 (C(60)(OOtBu)(2)Br(2)(OMe)(2)) with ROH/AgClO(4). Other related reactions have been investigated to explore the reactivity patterns. The structure of compound 6 was confirmed by single crystal X-ray analysis. 相似文献
98.
Ding S Luan D Boey FY Chen JS Lou XW 《Chemical communications (Cambridge, England)》2011,47(25):7155-7157
We demonstrate a new hydrothermal method to directly grow SnO(2) nanosheets on a graphene oxide support that is subsequently reduced to graphene. This unique SnO(2)/graphene hybrid structure exhibits enhanced lithium storage properties with high reversible capacities and good cycling performance. 相似文献
99.
Wang Z Luan D Madhavi S Li CM Lou XW 《Chemical communications (Cambridge, England)》2011,47(28):8061-8063
Polycrystalline α-Fe(2)O(3) nanotubes with thin walls have been synthesized by one-step template-engaged precipitation of Fe(OH)(x) followed by thermal annealing. In virtue of the unique structural features, these α-Fe(2)O(3) nanotubes exhibit superior lithium storage capabilities with exceptional high-rate capacity retention as a potential anode material for lithium-ion batteries. 相似文献
100.