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1.
Xiaobo He Jinghui Lyu Hu Zhou Guilin Zhuang Xing Zhong Jian‐Guo Wang Xiaonian Li 《International journal of quantum chemistry》2014,114(14):895-899
The adsorption mode of aromatic molecules on transition metal surfaces plays a key role in their catalytic transformation. In this study, by means of density functional theory calculations, we systematically investigate the adsorption of p‐chloroaniline on a series of Pd surfaces, including stepped surfaces, flat surfaces, and clusters. The adsorption energies of p‐chloroaniline on these substrates [Pd(221), Pd(211), Pd(111), Pd(100), Pd13‐icosahedral, Pd13‐cubo‐octahedron, Pd55] are ?1.90, ?2.13, ?1.70, ?2.11, ?2.53, ?2.65, ?2.23 eV, respectively. Benzene ring is adsorpted on catalyst rather than amine group in p‐chloroaniline molecular. A very good linear relationship is further found between the adsorption energies of p‐chloroaniline and the d‐band center of both Pd surfaces and clusters. The lower of d‐band center of Pd models, the stronger adsorption of p‐chloroaniline on catalysts. In addition, the frontier molecular orbital and density of states analysis explain the adsorption energy sequence: cluster Pd13 > stepped Pd(221) surface > flat Pd(111) surface. © 2014 Wiley Periodicals, Inc. 相似文献
2.
Filiz Ercan S. Gül Öztas Nilgün Ancm Tuncer Hökelek Mürside Tüzün Dinçer Ülkü 《Journal of chemical crystallography》1996,26(3):243-247
N-trans-cinnamylidene-m-toluidine (1) C16H15N, and N-trans-cinnamylidene-m-chloroaniline (2) C15H12NCl form isomorphous crystals which are monoclinic, space group P2l/c, with unit cell dimensionsa=5.967(2),b=13.793(3),c=15.048(5) Å, =91.97(3)° anda=5.868(2),b=13.788(4),c=15.191(4) Å, =91.87(3)°, respectively. The single-crystal X-ray structure determinations of the title compounds revealtrans structures. Ring (A) C10–15 and ring (B) C1–6, are practically planar in both structures with dihedral angels of 61.3(3) and 63.6(2)°, respectively.1H nmr, u.v. and i.r. spectra are also reported. 相似文献
3.
PmClAn基膜修饰电极的电化学及催化性质研究 总被引:2,自引:0,他引:2
聚苯胺作为电极修饰材料 ,已在传感器上显示出广泛的应用前景[1~ 4 ] .异丙醇 ( i- P)氧化[5,6 ] 是个较简单的反应 ,被广泛作为电催化研究的模型反应 .目前 ,i- P电化学氧化的研究集中于 Pt的多晶或单晶电极[7~ 9] ,Gonzales等 [10 ] 报道了 Pt- Sn共沉积的 PAn膜修饰电极上的异丙醇电氧化 ,但对复合材料的微观结构仍欠研究 .本文讨论 Pm Cl An基质性质对 Pt电沉积的影响 ,并探讨了 i- P在沉积 Pt微粒的 Pm Cl An功能膜电极上的氧化情况 .1 实验部分1 .1 电极的制备 聚间氯苯胺 ( Pm Cl An,本征态 ud,HCl掺杂态 d)采用乳液聚… 相似文献
4.
间氯苯胺的乳液聚合及聚合物链结构表征 总被引:2,自引:0,他引:2
聚苯胺以其良好的电化学稳定性和掺杂可逆性 ,成为一类优良的电活性聚合物 [1,2 ] ,但其溶解性差 ,限制了它的加工及应用 .用取代基对聚苯胺的结构进行修饰 ,可有效地提高其加工性能 [3,4 ] ,但有关含吸电子取代基的苯胺衍生物聚合的报道尚少 .Ranger等 [5]指出 ,含强吸电子取代基团的聚苯胺不易用化学氧化聚合方法制备 ,并提出被氧化单体中的 N7和 C4位置必须具有相近的电子自旋密度 ,才能进行“头 -尾”偶联 ,而含强吸电子取代基团的苯胺单体中这两个位置的反应能力是不等价的 ,但可采用与母体共聚的方法可制备含强吸电子取代基 (如— C… 相似文献
5.
N—(6—羟基—2,3,5—三氯苯磺酰基)对氯苯胺的结构与活性 总被引:3,自引:0,他引:3
肝片吸虫是一种严重危害草原畜群的寄生虫,为寻求新型高活性抗肝片吸虫病兽药已作了大量合成筛选工作以及活性与结构的关联研究。目前应用的多数抗肝片吸虫病兽药只对成虫有效,对童虫无效或低效,不能根除肝片吸虫。我们通过实验发现邻羟基苯磺酰基苯胺类衍生物对成虫及童虫均有效,关于该类衍生物的抗肝片吸虫活性,曾有专利报 相似文献
6.
Xiao-Xiang Han Ren-Xian Zhou Guo-hua Lai Xiao-Ming Zheng 《Reaction Kinetics and Catalysis Letters》2004,83(1):55-61
Hydrogenation of chloronitrobenzene (CNB) over PtM/ZrO2 (M= Cr, Mn, Fe, Co, Ni, Cu) catalysts has been studied in ethanol at 303 K and normal pressure.
The results show that the hydrogenetion of CNB can be carried out over PtM/ZrO2 catalysts. The order of the hydrogenation rates of CNB is p>m>o, and the yield of chloroaniline (CAN) is p>o>m.
PtFe/ZrO2 catalysts shows the highest catalytic activity on the hydrogenation of CNB. PtNi/ZrO2
catalyst shows good yield of CNB to CAN, and 93.3 mol% for o-CAN, 98.0 mol% for m-CAN
and 98.5 mol% for p-CAN, respectively.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
8.
Ni-Ce-P非晶态合金催化剂用于氯代硝基苯液相加氢制氯代苯胺 总被引:13,自引:0,他引:13
采用化学还原法制备了Ni-Ce-P非晶态合金催化剂,用X射线能谱、 X射线衍射、 选区电子衍射、 透射电子显微镜和差热分析等方法对催化剂的组成、结构、形貌及热稳定性进行了表征,讨论了Ni-Ce-P非晶态合金催化剂的催化性能和结构的关系,并以氯代硝基苯液相加氢合成氯代苯胺为探针反应考察了所制备催化剂的加氢性能. 研究结果表明,在不加脱卤抑制剂的情况下,在110 ℃下反应时所选4种反应物的转化率均可达99.8%, 脱卤率小于1.8%, 且Ni-Ce-P非晶态合金的活性为Ni-P非晶态合金催化剂的2倍,表现出较高的加氢性能和抑制脱卤性能. 相似文献
9.
M. A. Mora Laura Galicia Humberto Vzquez 《International journal of quantum chemistry》2000,78(2):99-111
Poly(aniline) is a subject of considerable scientific and technological interest. Its homologs such as poly(m‐chloroaniline) potentially offer similar physical‐chemical properties. In this work we present a comparative theoretical study between aniline and the m‐chloroaniline species at several levels of theory. To envisage the possible mechanism of polymerization, we have obtained geometries and electronic structures for the monomers and dimers as well as the corresponding cations and dications. Based on the monomer‐optimized geometries, atomic charges, bond orders, and spin densities, a head‐to‐tail coupling in the electrochemical polymerization is suggested. We have also calculated band gaps and ionization potentials. For the cationic dimers of aniline and m‐chloroaniline, the highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) energy difference has a smaller value, and oxidation at specific sites may be observed. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 78: 99–111, 2000 相似文献
10.
Hidetaka Yuge Miki Asai Atsushi Mamada Shin-Ichi Nishikiori Toschitake Iwamoto 《Journal of inclusion phenomena and macrocyclic chemistry》1995,22(1):71-87
The crystal structures of four novel Hofmann-diam-type clathrates [Cd(tn)Ni(CN)4]·1.72(o-MeC6H4NH2),3-o, [Cd(tn)Ni(CN)4]·0.5(m-ClC6H4NH2),3-m, [Cd(daptn)Ni(CN)4]·1.5(p-MeC6H4NH2),5-p and [Cd(dahpn)Ni(CN)4]·1.5(2-MeC9H6N),7-q have been determined by single crystal X-ray diffraction method [tn:n=3, daptn:n=5, dahpn:n=7 for NH2(CH2)
n
NH2.3-o crystallizes in the monoclinic space groupP2/m,a=7.538(2),b=9.314(5),c=7.670(2) Å, =91.03(2)°,Z=1,R=0.047 for 1252 reflections;3-m: orthorhombicPbam,a=12.1714(7),b=15.798(1),c=7.737(1) Å,Z=4,R=0.044 for 1871;5-p: monoclinicP21/a,a=13.736(3),b=22.014(4),c=7.762(3) Å, =91.04(3)°,Z=4,R=0.047 for 5281; and7-q: orthorhombicPbam,a=13.599(2),b=27.938(4),c=7.619(2) Å,Z=4,R=0.054 for 3098. Their host structures are topologically the same to those of the previously reported Hofmann-diam-type clathrates: the two-dimensional [CdNi(CN)4] networks are spanned by NH2(CH2)
n
NH2 at every Cd atom to build up the three-dimensional hosts. The number of cavities available for the guest is regulated by the deformation of the 2D networks and the diamine ligand in the host structure.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82192 (37 pages). 相似文献