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991.
钠、钙、铁对模型化合物热解及燃烧过程中氮逸出规律的影响 总被引:3,自引:4,他引:3
将卟唑在650℃,12MPa焦化条件下所得产物作为含氮模型化合物,在固定床反应器中研究了该模型化合物热解及燃烧过程中氮的逸出行为。结果表明,热解温度低于900℃时燃料氮主要停留在半焦中,HCN和NH3只占很小的部分;催化热解使HCN的量相对减少,NH3相对增加;半焦的反应性和燃烧条件影响半焦氮氧化生成NO,半焦的反应性越高,半焦氮对于NO的转化率越低;低温下催化剂使半焦氮对于NO的转化率升高,而高温下则相反。催化剂对于半焦燃烧时NO排放的影响还与半焦的性质有关,同一催化剂在相同的燃烧条件下对不同半焦燃烧的NO释放有不同的影响,预示半焦的性质和催化剂之间也有一定的匹配性。 相似文献
992.
993.
Mu Jie YANG Zong Wu YAO You Si CHEN Yang LI 《中国化学快报》2006,17(1):73-76
Humidity sensors have found wide applications in industry production, process control, environment monitoring, storage, electrical applications, etc.. Polymer electrolytes have been used in the preparation of resistive-type humidity sensors in the past ye… 相似文献
994.
He‐Dong Bian Jin‐Lei Tian Zhan‐Quan Liu Wen Gu Jing‐Yuan Xu Shi‐Ping Yan Dai‐Zheng Liao Zong‐Hui Jiang Peng Cheng 《无机化学与普通化学杂志》2004,630(2):327-330
The complex [Cu2(L)2(μ2‐C2O4)]·CH3OH ( 1 ) has been synthesized and characterized by IR, UV, ESR and variable temperature magnetic susceptibility measurement, where L = 1‐(ethylamino)‐2‐(salicylideneamino)ethane. The crystal X‐ray diffraction reveals that complex 1 has a μ2‐C2O42— bridge. The complex exhibits ferromagnetic couplings between the copper atoms bridged by oxalate dianion, which is rare in oxalato‐bridged copper complexes. 相似文献
995.
A unique coordination polymer, {[CuLNa(ClO4)]·H2O}n (1), was isolated from the solution containing sodium perchlorate and the neutral macrocyclic oxamidocopper(II) complex [CuL] (H2L = 2,3‐dioxo‐5,6:13, 14‐dibenzo‐7, 12‐bis(ethoxycarbonyl)‐1, 4, 8, 11‐tetraazacyclotetradeca‐7, 11‐diene). The complex is composed of [Na2Cu2] tetrametallacycles bridged by perchlorate ions to form infinite one‐dimensional chains which are stacked via τ‐τ interactions and weak coordination bonds to result in a two‐dimensional supramolecular network. The perclorate ions were found to coordinate to sodium atoms in the unusual bridging chelating tridentate mode of μ2‐(O:O′,O″). 相似文献
996.
997.
Reaction of the bridging ligand 3,6-bis-[6'-(1' ',8' '-naphthyrid-2' '-yl)-pyrid-2'-yl]pyridazine (1) with [Ru(DMSO)4Cl2] in aqueous ethanol followed by excess 4-substituted pyridine (4-R-py) in the presence of triethylamine provides a series of three well-organized dinuclear complexes characterized by 1H NMR, MS, and X-ray. Mononuclear analogues are prepared from 4-tert-butyl-2,6-di(1',8'-naphthyrid-2'-yl)pyridine (5) and characterized in a similar fashion. All six complexes show electronic absorption and redox properties consistent with the electron donor/acceptor ability of the axial 4-R-py ligand. When an acetonitrile solution of the catalyst is added to an aqueous Ce(IV)-CF3SO3H solution (pH = 1.0) at 24 degrees C, oxygen evolution is observed for both mono and dinuclear systems. Turnover numbers range from 50 to 3200 with the best results being found when the axial ligand is 4-methylpyridine (mononuclear TN = 580 and dinuclear TN = 3200). 相似文献
998.
Shu‐Ping Wang Dong‐Zhao Gao Dai‐Zheng Liao Zong‐Hui Jiang Shi‐Ping Yan 《无机化学与普通化学杂志》2006,632(3):491-494
A new coordination polymer of the formula [Ni(NIT4py)2(ip)(H2O)]n(NIT4py = 2‐(4′‐pyridinyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide and ip = isophthalate dianion) has been synthesized and characterized by elemental analyses, IR spectrum, and single‐crystal X‐ray diffraction. The coordination about each Ni2+ ion is a distorted octahedra. Each isophthalate dianion binds two Ni2+ ions in monodentate‐bidentate mode, leading to a 1‐D chain. Among the chains, the coordinated water molecules and carboxylato oxygen atoms form hydrogen bonds, generating an infinite 1‐D ladder structure of a double‐chain. The magnetic study shows that the decrease of χMT value in the low temperature for the complex is mainly ascribed to the zero‐field splitting of the distorted octahedral Ni2+ ions. 相似文献
999.
Jin‐Kui Tang Li‐Na Zhu Xiao‐Zeng Li Wen Dong Dai‐Zheng Liao Zong‐Hui Jiang Shi‐Ping Yan Peng Cheng 《无机化学与普通化学杂志》2003,629(11):2000-2003
A novel coordination polymer {[Mn(azpy)(NCS)2(MeOH)2] · azpy}n( 1 ) (azpy = 4, 4'‐azopyridine), has been synthesized and characterized by X‐ray diffraction. It consists of a quasi two‐dimensional network structure constructed from 1‐D chains of [Mn(azpy)(NCS)2(MeOH)2]n connected by hydrogen bonds, which creates about 13.6 Å × 17.1 Å of channels. The coordination sphere of the manganese(II) ion is a distorted octahedron. The determination of the variable temperature magnetic susceptibilities (5—300 K) shows the existence of a very weak antiferromagnetic interaction with a J value of —0.03 cm—1. 相似文献
1000.
Xiang-shan?WangEmail author Zhao-sen?Zeng Da-qing?Shi Xian-yong?Wei Zhi-min?Zong 《Journal of chemical crystallography》2005,35(3):243-247
The X-ray crystal structure of 2-amino-3-cyano-4-(4-methylphenyl)-6-methoxyl-1,4,9,10-tetrahydrobenzo [f]chromene 1, C22H20N2O2, is determined. The crystals of compound 1 are triclinic, space group P-1, a = 10.120(1), b = 13.127(1), c = 15.203(2) Å, = 67.841(9), = 80.81(1), = 77.58(1), Z = 4, V = 1819.7(4) Å3. It is interesting that all the atoms of the pyran ring are coplanar, which is different from other similar compounds. The structure is stabilized by intermolecular hydrogen bonds. 相似文献