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31.
电化学合成铜配合物的研究 总被引:3,自引:0,他引:3
采用金属铜为"牺牲"阳极,首次在无隔膜电解槽中,电化学溶解金属铜一步制备了纳米CuO前体Cu(OEt)2, Cu(OBu)2, Cu(acac)2, Cu(OEt)(acac), Cu(OBu)(acac) (acac为乙酰丙酮基).产物通过红外光谱(FT-IR)、拉曼光谱(Raman spectrum)进行表征.同时讨论了影响电合成铜醇盐及其配合物的关键因素.实验表明,防止阳极钝化,温度控制在30~50 ℃,采用有机胺溴化物为导电盐, 电极电位控制在0.8~1.2 V之间,可以提高电合成效率.实验同时表明Cu(acac)2, Cu(OEt)(acac), Cu(OBu)(acac)可作为制备含铜纳米材料前驱体. 相似文献
32.
The reactions of π-cyclopentadienylnickel carbonyl dimer with 3,3,3-trimethylpropynyldiphenylphosphine and phenylethynyldiphenylphosphine are described. The products have been characterized by elemental and mass spectral analysis, infrared and NMR spectroscopy. An acetylene bridged complex (π-C5H5Ni)2Ph2PC2-t-Bu, containing an uncoordinated phosphorus atom, has been prepared. The complex can be oxidized to the phosphine oxide derivative (π-C5H5Ni)2Ph2P(O)C2-t-Bu and converted to the phosphonium salts with methyl iodide or ethyl bromide. These are the first reported π-complexes of phosphonium salts. The complex (π-C5H5Ni)2Ph2PC2-t-Bu forms the novel mixed metal derivative [PdCl2][(π-C5H5Ni)2Ph2PC2-t-Bu]2 from bis(benzonitrile)-palladium dichloride. The dicarbonyl complexes Ni(CO)2(Ph2PC2R)2 (R t-Bu, Ph), the phosphine oxide complex (π-C5H5Ni)2(Ph2P(O)C2Ph) and the trinuclear nickel carbonyl derivative Ni(CO)3[(π-C5H5Ni)2Ph2PC2Ph] are described. 相似文献
33.
Experimental data on initial hydrate formation conditions have been obtained for the nitrogen-propane-water system in the L1HG, L1L2H, and L1L2HG regions, where L1 is the water rich liquid phase, L2 is the hydrocarbon rich liquid phase, H is the hydrate and the G is the vapor phase. The measurements covered a range of temperatures from about 275 to 293 K and pressures from about 0.3 to 17.0 MPa. The concentrations covered for the L1HG region extended from 0.94 to 75.0 mole percent propane in the gas phase, and for the L1L2H region they extended from 83.1 to 99.0 mole percent in the condensed liquid phase. Four-phase measurements were made at concentrations of propane from 18.1 to 71.1 mole percent in the gas phase.The experimental data were used to find a fitted binary interaction parameter for predicting hydrate formation in systems containing nitrogen and propane. 相似文献
34.
The attempted Baylis-Hillman reactions of N-tosyl aldimines and aryl aldehydes with 3-methylpenta-3,4-dien-2-one gave the corresponding Baylis-Hillman adducts 3 and 6 in moderate to good yields in the presence of DMAP in DMSO, respectively. In the case of the aza-Baylis-Hillman reactions of N-tosyl aldimines with 3-methylpenta-3,4-dien-2-one catalyzed by PBu3, the corresponding aza-Baylis-Hillman derivatives 4 and 5 were formed at the same time. 相似文献
35.
Ai‐Hua Zhao Yan Zhang Zhao‐Hui Xu Jian‐Wen Liu Wei Jia 《Helvetica chimica acta》2004,87(12):3160-3166
Three new enmein‐type ent‐kaurenoids, i.e., the two pairs 1 and 2 of 20‐epimers and the (20R)‐isomer 3 , besides the seven known diterpenoids 4 – 10 , were isolated from the aerial parts of Isodon serra. Their structures were elucidated by spectroscopic techniques and X‐ray diffraction. The immunosuppressive effect for T‐lymphocytes proliferation induced by Con A in BALB/c mouse was evaluated for the isolates 1 – 10 . They all displayed a remarkable inhibitory effect, with multi‐glycosides of Tripterygium wilfordii as positive reference substance (Table 3). 相似文献
36.
Lei He Hui‐Min Liu Xiao‐Lan Luo Wen‐Qin Zhang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(2):o104-o106
The title compound, 2‐{N‐[2‐(2‐hydroxybenzamido)ethylammonioethyl]aminocarbonyl}phenolate, C18H21N3O4, crystallizes in a zwitterionic form as a result of intermolecular proton transfer and possesses a negatively charged phenolate group and a protonated amino group. The 2‐hydroxybenzamide and 2‐(aminocarbonyl)phenolate moieties attached to the two ends of the C—C—N—C—C backbone adopt a cis conformation in relation to this backbone. All N‐ and O‐bound H atoms are involved in hydrogen‐bond formation; the zwitterions are first linked into head‐to‐tail dimers, which are further organized into a two‐dimensional network parallel to the crystallographic bc plane. 相似文献
37.
Min Ming Tang 《Journal of Mathematical Analysis and Applications》1977,57(2):368-381
In this paper we study the behavior of solutions of some quasilinear parabolic equations of the form as t → ∞. In particular, the solutions of these equations will decay to zero as t → ∞ in the L∞ norm. 相似文献
38.
A number of experimental parameters have been optimized for the separation of 26 metal ions, including alkali, alkaline earth, transition and lanthanide metal ions. Experimental parameters that were evaluated included nature of indirect-detection reagent, pH of electrolyte, concentration of complexing agent and nature of the surface of the capillary; unbonded and C1 and C18 bonded phases were studied. In addition the effect of internal diameter on linearity and signal-to-noise ratio was examined, and separation efficiency was determined for a variety of experimental conditions. Detection limits (signal-to-noise RATIO = 3) were ca. 1 μg/ml for the lanthanides, ca. 0.6 μg/ml for transition and alkaline earth ions and ca. 0.1–0.8 μg/ml for alkali metal ions. The average relative standard deviations of were 3.7, 5.1 and 2.5% on unbonded, C1 and C18 capillaries, respectively. Whereas conventional regression analysis suggested that the calibration curves were linear over the range of 1·10−5 to 4·10−4 mol/l, sensitivity plots showed that the results were actually linear to within 6% only over the range of 2.5·10−5 to 4·10−4 mol/l. 相似文献
39.
Studies of the electrochemical behavior of epinephrine at a homocysteine self-assembled electrode 总被引:6,自引:0,他引:6
The self-assembled electrode with the homocysteine monolayer (Hcy/Au) has been characterized by infrared spectroscopy and ac impedance spectroscopy in electrolyte. The Hcy/Au electrode is demonstrated to promote the electrochemical response of epinephrine (E) by cyclic voltammetry. A pair of well-defined redox waves was obtained and the calculated standard rate constant (ks) is 2.1×10−2 cm s−1 at the self-assembled electrode. The reduction peak of E can be used to determine the concentration of E in presence of ascorbic acid (AA) owing to the Hcy/Au also promoting the electrochemical oxidation of AA. 相似文献
40.
Highly ordered mesoporous silica can be regenerated from a mesoporous carbon CMK-3 that is a negative replica of mesoporous silica SBA-15, indicating reversible replication between carbon and inorganic materials. 相似文献