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91.
通过在螺噁嗪结构中的萘环8′-位上引入不同的取代基,合成了三种螺噁嗪光致变色化合物;对三种产物的光谱性质进行了对比研究,并考察了其光照褪色速率和抗疲劳性能.结果表明:改变8′-位取代基,合成化合物的闭环吸收峰的位置几乎不受影响,但开环吸收峰发生显著变化,随着取代基极性增加明显红移.增加溶剂的极性,可使同一化合物的开环吸收峰红移.  相似文献   
92.
Three novel indolo[3,2-b]carbazoles derivatives were successfully synthesized by condensation reaction and structurally characterized by elemental analysis, mass spectrometry and proton nuclear magnetic resonance spectroscopy methods, which belong to donor-π-acceptor systems comprising an indolo[3,2-b]carbazole group as an electron donor and two benzothiazole rings as electron acceptors. The thermal, electrochemical and photophysical properties of the compounds were characterized by thermogravimetric analysis combined with electrochemistry, UV-vis absorption spectroscopy and fluorescence spectroscopy. On the other hand, the geometries, molecular orbitals, charge-injection and transport properties were determined by quantum chemical calculations. The results show that the compounds synthesized exhibit good thermal stability and high fluorescence quantum yields, indicating the potential application as optoelectronic materials.  相似文献   
93.
Described herein is the first example of an organocatalytic approach for acylanion addition to the anomeric carbon of 2-nitroglucal using an N-heterocyclic carbene catalyst. Control over the reaction conditions gives β-selective and nitro-eliminated C-glycosides, providing opportunities to produce new classes of C-glycoside.  相似文献   
94.
两亲性丙烯酸酯共聚物的聚合研究   总被引:1,自引:0,他引:1  
刘莉  张文传 《合成化学》1998,6(4):365-371
利用过氧化苯甲酰为引发剂探讨了甲基丙烯酸β-羟乙酯和丙烯酸长链烷基酯的自由基共聚合。重点讨论了合成条件如溶剂、沉淀剂、引发剂用量、单体配比、反应时间等对共聚反应的影响以及各种聚合条件对该共聚物的组成、结构和性能的影响。并用IR,GPC,^13CNMR等手段对共聚物进行了表征。  相似文献   
95.
Alargenumberofadditionsto[6O]fullerenehavebeeninvestigated.However,mostoftheworkhaveconcentratedontheformationofthemono-additionproductS0f[60]fullerene'-Thedevelopment0fselechveroutestomultipleadductShascurrentlybecomethefrontierinthechendstryof[60]fuIlerene'~'.FollowingtheaPplicahonoftether-directedremotefunctionalizati0ntotheregi0specificformati0nofthedi-andtriadductSof[60]fullerene,F.Diederichetal6alsodescribed'awayforthedirectdifunctionalizationof[60]fullerenebasedonacyclizationreachono…  相似文献   
96.
A novel cationic gemini surfactant has been readily synthesised in 70 % total yield. The functional gemini surfactant can act both as an emulsifier and an atom transfer radical polymerisation (ATRP) initiator in mini-emulsion polymerisation of methyl methacrylate (MMA), in which no other emulsifier was required. 1-(Dimethylamino)dodecane (N,N-dimethyldodecylamine, DMDA) was found to be a good ligand in the activator generated by electron transfer (AGET) ATRP reaction. Kinetic studies indicated that the polymerisation featured controlled/living radical polymerisation.  相似文献   
97.
98.
As a new nano-scale functional material, it is necessary to achieve a uniform distribution in the composites for gaining the CNFs’ excellent reinforcing effect. In this paper, CNFs were purified by the method of high temperature annealing treatment. Six surfactants, methylcellulose (MC), hydroxypropyl methylcellulose (HPMC), sodium dodecyl sulfate (SDS), dodecylamine (DDA), N, N-dimethyl formamide (DMF) and cetyltrimethyl ammonium bromide (CTAB) were used individually and combinatorially in a certain concentration to disperse the CNFs in aqueous solution. To achieve a good dispersion of the CNFs, a method utilizing ultrasonic processing was employed. The CNFs treated by the method of high temperature annealing treatment were characterized by differential thermal analysis (DTA) and thermogravimetry analysis (TGA), and the ultrasonication-driven dispersion of CNFs in aqueous solutions were monitored by UVvis spectroscopy and transmission electron microscopy (TEM). The experiments reveal that the method of high temperature annealing treatment purified the CNFs and the maximum achievable dispersion of CNFs corresponds to the maximum UV absorbance of the solution. All results show that the surfactants mixture of MC and SDS in a certain concentration of 0.4 and 2.0 g/L has the maximum dispersion effect on CNFs in aqueous solution, the optimum concentration ratio of MC, SDS, and CNFs was 2: 10: 1.  相似文献   
99.
金灿  王川  涂国良  俞传明 《合成化学》2013,21(1):106-108
以1-氨基环戊腈草酸盐为起始原料,经双氧水水解、戊酰氯酰化、环合制得厄贝沙坦的关键中间体——2-丁基-1,3-二氮杂螺[4.4]壬-1-烯-4-酮,总产率80.9%,其结构经1H NMR,13C NMR和MS确证。  相似文献   
100.
A nickel hydroxide-modified nickel electrode (Ni(OH)2/Ni) was successfully prepared by the cyclic voltammetry (CV) method and the electrocatalytic properties of the electrode for formaldehyde and methanol oxidation have been investigated respectively. The Ni(OH)2/Ni electrode exhibits high electrocatalytic activity in the reaction. A new method has been developed for formaldehyde determination at the nickel hydroxide-modified nickel electrode and the experimental parameters were optimized. The oxidation peak current is linearly proportional to the concentration of formaldehyde in the range of 7.0 × 10?5 to 1.6 × 10?2 M with a detection limit of 2.0 × 10?5 M. Recoveries of artificial samples are between 93.3 and 103.5%. The effect of scan rate and methanol concentration on the electrochemical behavior of methanol were investigated respectively.  相似文献   
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