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2.
《Polyhedron》2003,22(14-17):2009-2012
Magnetisation study of the C60·TMTSF·2CS2 molecular complex in magnetic field up to 47 T for the temperature range 1.8–300 K and ESR spectroscopy of the molecular complex (ET)2C60 at T=1.8 K for the frequency range 60–90 GHz in magnetic field up to 32 T provide the experimental evidence that a paramagnetic centers with the reduced g-factor values g<1 control magnetic properties of these solids. Anomalous g-factor values may be caused by dynamic Jan-Teller effect on the negative C60 ions, which appear as defects in crystalline structure with a weak charge transfer.  相似文献   

3.
Incorporation of organic radical TEMPO into photochromic biindenylidene system leads to the synthesis of a novel dual functional compound 4. Its photochromism, structure, magnetic properties as well as ESR spectroscopy were deliberately investigated. Remarkable changes of the ESR spectra were observed for 4 upon photoirradiation with different light sources. The intermolecular interactions were interpreted with regard to its crystal structure.  相似文献   

4.
The humulanolides are a series of sesquiterpene lactones, most of which have unique and challenging structure. The humulanolides have exhibited anticancer activity. The combinations of fascinating structural motifs and promising pharmacological properties have prompted significant interest in the synthetic community. In this review, we provide a summary of recent progress regarding the total synthesis of humulanolides.  相似文献   

5.
生物有机硅化合物研究新进展   总被引:1,自引:0,他引:1  
本文概述了近十几年生物有机硅化学的新进展。全文分三部分:1)利用有机硅基取代有机药物中的活性官能团的硅基化反应;2)有机药物中的某一碳原子被硅原子取代的硅药(sila-drugs)研究;3)在有机药物中没有类似结构的具有生物活性的新型有机硅化合物研究。  相似文献   

6.
综述了近年来烯烃自由基环化反应的研究进展,主要包括通过烯烃的自由基环 化反应合成内酯、内酯胺及一些含杂原子的环状化合物,同时对烯烃自由基环化反 应新进展--超临界二氧化碳流体作为反应介质也作了阐述。  相似文献   

7.
Several organic radical compounds based on TEMPO radical with cholesterol and benzylideneamine cores (3a-c) were prepared. The radical compounds were found to freeze into glassy state when cooled from their isotropic liquid state and characteristic heat-responsive magnetic properties were observed in the radicals due to the phase transitions.  相似文献   

8.
This review provides a brief overview of the recent research progress of pure organic mechanoluminescence. Depending on whether the external light excitation is required, mechano-responsive conjugated molecules with mechanofluorochromic and triboluminescent properties are discussed respectively. Challenges and opportunities in this specific research area are proposed as well.  相似文献   

9.
有机荧光材料研究进展   总被引:21,自引:3,他引:21  
对三类主要的有机荧光材料--具刚性结构的芳香稠环化合物,具共轭结构的分子内电荷转移化合物及某些金属配合物尤其是稀土金属配合物近二十年来的研究与应用进行了综述,引用文献48篇。  相似文献   

10.
活性自由基聚合(Living radical polymerization,LRP)是高效可控地制备结构新颖的高分子材料的重要方法,近年来逐渐成为高分子合成领域的研究热点.本文综述了一类重要的活性自由基聚合方法,即有机金属配合物控制的自由基聚合(Organometallic mediated radical polymerization,OMRP)的最新研究进展,介绍了钛、钒、铬、钼、铁、锇、钴、铑、钯和铜等有机金属配合物为催化剂控制的OMRP,并简述了OMRP方法在光致LRP、嵌段共聚物的合成、与其他LRP方法联用及聚合物端基修饰和转化等方面的拓展.此外,本文还对有待进一步深入探索的领域和问题提出了建议和展望.  相似文献   

11.
An efficient and stable white organic light emitting diode (WOLED) is highly desirable in potential applications such as lighting, background light source, and full color display.A series of highly fluorescent dyes based on a dipyrazolopyridine skeleton,1,7-diphenyl-l,7-dihydrodipyrazolo[3,4-b,4′,3′-e]pyridine, were synthesized and evaluated as emitting as well as charge-transporting material in the fabrication of electroluminescent devices.Several of the blue derivatives are found to be useful as the source of blue emission in fabricating bright white-emitting devices. The choice of dopants, cathode materials, electron-transporting materials as well as the device configurations greatly affect the emission profile, efficiencies, as well as the device lifetime. The latest progress in achieving a more efficient, color stable, durable white light device will be discussed.  相似文献   

12.
丁兰  王慧 《色谱》2013,31(2):93-94
1海胆状磁性二氧化钛微球的合成及在磷酸化多肽选择性富集中的应用 2磁性表面分子印迹聚合物的合成与应用 3磁性氧化碳纳米管用于细胞内核酸相关蛋白质的提取 4一步法制备具有C8修饰的磁性介孔限制性通过吸附剂及应用 5磁性管内固相微萃取技术  相似文献   

13.
By employing calorimetric and cryometric methods, the melting total and the premelting enthalpies of stearic acid were measured and the phase diagrams of the solid-liquid equilibria stearic acid +A (whereA is an aromatic compound or a dicarboxylic acid or I2) were determined.
Zusammenfassung Die Gesamt-Schmelz-Enthalpie und die Vor-Schmelz-Enthalpie der Stearinsäure werden unter Anwendung kalorimetrischer und kryometrischer Methoden gemessen und die Phasendiagramme der festflüssigen Gleichgewichte von Stearinsäure+A (wobeiA eine aromatische Verbindung oder eine Dicarbonsäure oder I2 ist) bestimmt.

Résumé Mesure de l'enthalpie totale de fusion de l'acide stéarique, ainsi que de celle de pré-fusion, par calorimétrie et cryométrie. Etablissement des diagrammes de phases pour les équilibres solide-liquide du système acide stéarique +A;A désignant un composé aromatique ou un acide dicarboxylique ou I[in2].

- + ( . I2).
  相似文献   

14.
This review summarizes and puts into context recent advances in the field of redox-switched binding processes, with particular reference to the interaction between redox-active compounds and organic compounds, both charged and neutral. Simple homogeneous, two-component systems are discussed at first as a precursor to sections on more advanced systems (e.g. multi-component and multi-pole) and binding processes involving components attached to a surface.  相似文献   

15.
Journal of Thermal Analysis and Calorimetry - Calorimetric and cryometric methods were employed to measure the enthalpy and entropy of fusion of caprylamide and stearamide.  相似文献   

16.
Hypervalent iodine compounds constitute a well-established and broadly used reagent family in organic synthesis. As they are usually either used in stoichiometric quantities or generated in situ from an aryl iodide precursor using a terminal oxidant, the associated waste and separation problems pose major challenges en route to sustainable and scalable processes. In this regard, the use of inexpensive electric current as a traceless oxidant for the in-situ generation of hypervalent iodine has emerged as a promising alternative. This review summarizes the advances over the past 2 years, including improved electrolysis protocols, new synthetic applications, and concepts for enhancing the sustainability of the reactions.  相似文献   

17.
Phenolic compounds are an important class of chemicals with various beneficial bioactivities. However, they are usually poorly soluble in water and unstable while some of them are toxic. Glycosylation can significantly improve the solubility, stability, and bioactivity of phenolic compounds. The enzymatic method for glycosylation can form a specific glycosidic bond in one step and under environment-friendly conditions. This review covers the progress made in the application of two classes of enzymes, namely, glycosyltransferases and glycosidases, for the glycosylation of phenolic compounds, and illustrates the impact of glycosylation on the properties of these compounds.  相似文献   

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Chemistry of Heterocyclic Compounds - In recent years several important viral infections have emerged and antiviral chemotherapeutic agents are not sufficiently effective in clinic, leading to...  相似文献   

20.
Rate constants for a series of alcohols, ethers, and esters toward the sulfate radical (SO4?) have been directly determined using a laser photolysis set‐up in which the radical was produced by the photodissociation of peroxodisulfate anions. The sulfate radical concentration was monitored by following its optical absorption by means of time resolved spectroscopy techniques. At room temperature the following rate constants were derived: methanol ((1.6 ± 0.2) × 107 M?1 s?1); ethanol ((7.8 ± 1.2) × 107 M?1 s?1); tert‐butanol ((8.9 ± 0.3) × 105 M?1 s?1); diethyl ether ((1.8 ± 0.1) × 108 M?1 s?1); MTBE ((3.13 ± 0.02) × 107 M?1 s?1); tetrahydrofuran (THF) ((2.3 ± 0.2) × 108 M?1 s?1); hydrated formaldehyde ((1.4 ± 0.2) × 107 M?1 s?1); hydrated glyoxal ((2.4 ± 0.2) × 107 M?1 s?1); dimethyl malonate (CH3OC(O)CH2C(O)OCH3) ((1.28 ± 0.02) × 106 M?1 s?1); and dimethyl succinate (CH3OC(O)CH2CH2C(O)OCH3) ((1.37 ± 0.08) × 106 M?1 s?1) where the errors represent 2σ. For the two latter species, we also measured the temperature dependence of the corresponding rate constants. A correlation of these kinetics with the bond dissociation energy is also presented and discussed. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 539–547, 2001  相似文献   

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