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61.
The polymerization rates of three cyanopyridines catalyzed by cuprous chloride-zinc system are measured, and the structure of the formed polymer is also determined. Compared with aromatic nitrile, cyanopyridines polymerize faster and form polyconjugated polymer with skeleton—(C=N)—_n instead of triazine structure. This chain-polymer possesses semiconductive property, and can be converted into conductive material by thermal treatment. In addition, the polymerization kinetics of 3-cyanopyridine catalyzed by 3-cyanopyridinium perchlorate is investigated. It is found that the polymerization rate is directly proportional to the concentrations of monomer and catalyst, and the activation energy of the polymerization is 103.1 KJ/mol. 相似文献
62.
As in the case of reinforcing filler-induced increase in hysteresis in rubbers, placement of aluminum (A1) foil to the surface of a rubber blend of epichlorohydrin rubber and carboxylated nitrile base induces increased hysteresis of the rubber due to adhesion between Al and the rubber blend. Changes in hysteresis loss due to Al foil can be correlated with the peel strength of Al-rubber-Al joints. © 1995 John Wiley & Sons, Inc. 相似文献
63.
利用双酚-S与苯甲酰氯形成的二元酚酯在AlCl3作用下进行Fries重排制备3,3′-二苯甲酰基双酚-S,以此与二氯苯甲腈进行缩聚反应合成了带苯甲酰基侧基的聚芳醚腈。 相似文献
64.
A novel and simple enzymatic method for the determination of trace cyanide in marine fish is presented. This method is based on the conversion of metal-cyanide complexes by a fungal enzyme extract containing cyanide hydratase (E.C. 4.2.1.66; CyHT) and formamidase (E.C. 3.5.1.49) into formate and ammonia. The formate produced in the sample pretreated with the fungal enzymes was measured by adding formate dehydrogenase (E.C. 1.2.1.2; FDH) and excess NAD+. The NADH formed accordingly was monitored at 340nm. The cyanide calibration curve was found to be linear in the range of 10–100µM, and the detection limit was 1.1µM (0.0286ppm). The proposed biotest was successfully applied to the determination of trace cyanide in a tropical marine food fish species (Russells Snapper (Lutjamus russellii)) which had been exposed to cyanide. 相似文献
65.
The mechanical and damping properties of blends of ethylene-vinyl acetate rubber (VA content >40% wt) (EVM)/ethylene-propylene-diene copolymer (EPDM) and EVM/nitrile butadiene rubber (NBR), both with 1.4 phr BIPB (bis (tert-butyl peroxy isopropyl) benzene) as curing agent, were investigated by dynamic mechanical analysis (DMA). The effect of added polyvinyl chloride (PVC), amido donor N-cyclohexyl-2-benzothiazole sulfonamide (CZ), and dicumyl peroxide (DCP) as a substitute curing agent, on the damping and mechanical properties of both rubber blends were studied. The results showed that in EVM/EPDM/PVC blends, EPDM was immiscible with EVM and could not expand the damping range of EVM at low temperature. PVC was miscible with EVM and dramatically improved the damping property of EVM at high temperature while keeping good mechanical performance. In EVM/NBR/PVC blends, PVC was partially miscible with EVM/NBR blends and remarkably widened the effective damping temperature range (EDTR) from 41.1°C for EVM/NBR to 62.4°C. Curing agents BIPB and DCP had a similar influence on EVM/EPDM blends. DCP, however, dramatically raised the height of tan δ peak of EVM/NBR = 80/20 and expanded its EDTR to 64.9°C. CZ had no obvious influence on the EVM/EPDM blends cured with BIPB. However, a small content of CZ enlarged the tan δ peak of EVM/NBR = 80/20 in both height and width, but at the cost of a deterioration of mechanical performance. 相似文献
66.
67.
Isoxazoline and isoxazolidine series were obtained by the reactions of aromatic aldonitrones and nitrile oxides with N-vinyl caprolactam via regioselective 1,3-dipolar cycloadditions that yield only 5-caprolactam-substituted regioisomers in moderate yields. The cycloaddition reactions were optimized using different conditions. The utilized one for the transformation of nitrile oxides to isoxazoles is triethylamine at room temperature and the best protocol have been found for the transformation of nitrones to N-methyl isoxazolidines is silver acetate in refluxing xylene. The structural identification of target compounds was established by IR, nuclear magnetic resonance (NMR), high resolution mass spectrometry (HRMS) spectra, and X-ray diffraction analyses. 相似文献
68.
Ian R. Pottie C. V. Krishnamohan Sharma Keith Vaughan Michael J. Zaworotko 《Journal of chemical crystallography》1998,28(1):5-10
The crystal and molecular structure of 1,2-bis-{1-(2-cyanophenyl)-3-methyltriazen-3-yl-}ethane (1) and 1,2-bis-{1-(2-methoxyphenyl)-3-methyltriazen-3-yl-}ethane (2) have been determined by single crystal X-ray diffraction analysis. Bis-triazene (1) exists as the staggered conformation in the solid state, with an anti-anti configuration around the N2–N3 bond of the triazene units, whereas 2 assumes a gauche conformation with the syn-syn configuration in the triazene units. Crystal data: 1 C18H18N8, triclinic, space group P –1, a = 6.108(2), b = 8.118(3), c = 9.600(4)Å, = 101.37(7)°, = 96.47(7)°, = 102.71(5)°, V = 449.1(3)Å3, Z = 2; 2 C18H24N6O2, monoclinic, space group P 21/n, a = 13.119(5), b = 7.745(2), c = 19.201(2)Å, = 96.47(7)°, V = 1910.3(9)Å3, Z = 4. 相似文献
69.
P. A. Troshin A. S. Peregudov S. I. Troyanov R. N. Lyubovskaya 《Russian Chemical Bulletin》2008,57(5):887-912
The results of the authors’ studies on the [2+3] cycloaddition of azomethine and nitrile ylides generated from picolylamine
and benzylamine derivatives to fullerenes are systematized and new experimental data are considered. Catalysts and microwave
radiation promoting the formation of ylides and their addition to fullerenes were successfully used for the first time. A
large series of new pyrrolidine and pyrroline derivatives of fullerenes C60 and C70 were synthesized and characterized. The proposed procedures afford the reaction products in yields twice as high (80–85%)
as those attained by the classical Prato reaction. The reactions proceed with virtually complete regio- (in the case of C70) and stereoselectivity to afford only cis-2′,5′-disubstituted and trans-1′,2′,5′-trisubstituted pyrrolidinofullerenes. Pyridyl-substituted pyrrolidinofullerenes react with metalloporphyrins and
phthalocyanines to form self-ordered coordination complexes. The latter are analogs of natural photosynthetic antenna systems
due to photoinduced charge separation that occurs in these complexes upon exposure to light.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 873–898, May, 2008. 相似文献
70.
This paper reports the fuel cells (DMFC and PEMFC) performance using sulfonated poly(arylene ether ether nitrile) (SPAEEN) copolymers containing sulfonic acid group arranged in structurally different ways. The membrane electrode assembly (MEA) fabricated from SPAEEN containing 60 mol% of angled naphthalenesulfonic acid group (m-SPAEEN-60) had superior performance over those derived from pendent naphthalenesulfonic acid group (p-SPAEEN) or sulfonated hydroquinone (HQ-SPAEEN) in H2/air and/or DMFC conditions. For example, the current density of the MEA using m-SPAEEN-60 at 0.5 V and 2.0 M methanol was 250 mA/cm2, whereas the current densities of the MEAs using p-SPAEEN-50 and HQ-SPAEEN-56 were 185 and 190 mA/cm2, respectively. In addition, compared with the sulfonated polysulfone (BPSH-35) and Nafion membranes, the copolymer containing nitrile group showed the improved cell performance. For example, the power density of the MEA using m-SPAEEN-60 at 250 mA/cm2 and 2.0 M methanol was 125 mW/cm2, whereas the power densities of the MEAs using sulfonated polysulfone (BPSH-35) and Nafion were 115 and 113 mW/cm2, respectively. m-SPAEEN-60 showed stable cell performance during extended operation (>100 h). 相似文献