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51.
E. U. Franck 《Journal of solution chemistry》1973,2(2-3):339-356
A survey is given of recent experimental results obtained from high-temperature, high-pressure investigations with water, aqueous solutions, and ionic fluids. Data on the static dielectric constant of water to 550°C and 5 kbar are given and discussed with respect to their relation to water structure. Infrared and Raman spectra of HDO in pure water have been obtained to 400°C and 4 kbar, which give information on hydrogen bonding. Xe–H2O and CO2–H2O mixtures were investigated in the infrared. Ni(II) and Cu(II) complexes were investigated by absorption spectroscopy in aqueous solutions of high chloride content to 350°C and 2–6 kbar. The gas-liquid critical point of ammonium chloride was found at 880°C and 1635 bars. This fluid appears to be predominantly ionic even in the critical region. The possibility of converting pure polar fluids such as ammonia and water into concentrated ionic solutions by self-ionization at very high pressures is mentioned.This paper was presented at the symposium, The Physical Chemistry of Aqueous Systems, held at the University of Pittsburgh, Pittsburgh, Pennsylvania, June 12–14, 1972, in honor of the 70th birthday of Professor H. S. Frank. 相似文献
52.
Monir Uddin Antonis G. Hatzidimitriou Maria Lalia-Kantouri Chris Tsiamis 《Structural chemistry》1997,8(2):131-139
The infrared and electronic excitation spectra of a series of new nickel(II) chelates containing an-diimine (or nitrogenous base, enR) and the anion of a-dione (1,3-ketoenol or 1,3-ketoester,H) were obtained in the solid state and in solution. The composition and the overall structure of the new chelates in the solid state depends on ligand concentration, the substituents within the-dionato moiety and the counterion present. The IR and electronic excitation spectra of [Ni(enR)2
]NO3 and [Ni(enR)(O2NO)] indicate, in conjunction with other physicochemical measurements, bidentate coordination of the ligands, while the spectral shifts reveal replacement of the (O,O)nitrato group by basic solvents. The existence of the nickel(II) in an octahedral environment is confirmed by an X-ray structure analysis of [Ni(dpamH)2acac]NO3 · CH3OH (monoclinic, space groupP2l/n, a=17.296(1),b=7.462(1),c=21.604(3) å,=95.65(1),Z=4, R=0.0534,Rw=0.0600), where dpamH denotes the 2,2-dipyridylamine. 相似文献
53.
Woo-Jin Lee Su-Il Pyun Tae-Hyun Yang Joong-Do Kim Young-Ho Baek Han-Gyu Kim 《Journal of Solid State Electrochemistry》1997,1(2):120-125
Hydrogen transport through a Pd-Ni alloy electrodeposited on a Pd substrate (Pd-Ni/Pd bilayer symmetric electrode) has been
investigated using cyclic voltammetry and a.c. impedance spectroscopy combined with the electrochemical hydrogen permeation
method. The permeation build-up current transients and the measured impedance spectra were analyzed using the time-lag method
for the bilayer electrode and a complex non-linear least squares data-fitting method based upon the derived Faradaic admittance
for the hydrogen absorption into and diffusion through the bilayer electrode under the permeable boundary condition, respectively.
The value of the hydrogen diffusivity in the Pd-Ni layer was lower than that in the Pd layer. Furthermore, the values of the
charge transfer resistance and equilibrium absorption constant for the Pd-Ni/Pd bilayer electrode were higher than those for
the Pd single layer electrode. From the experimental results, the role of the thin Ni(OH)2 film formed on the Pd-Ni layer surface in the hydrogen transport through the Pd-Ni/Pd bilayer electrode is discussed in terms
of its passivating effect and extremely large hydrogen solubility.
Received: 22 January 1997 / Accepted: 15 April 1997 相似文献
54.
P. C. Hinnen W. Hogervorst S. Stolte W. Ubachs 《Applied physics. B, Lasers and optics》1994,59(3):307-310
A narrowband tunable eXtreme UltraViolet (XUV) laser source is used for a high resolution study of the Lyman (B
1
u
+
X
1
g
+
) band system of molecular hydrogen. Seven rotational transitions of two vibrational bands, (10,0) and (11,0), in the wavelength range from 97.2–98.3 nm have been investigated for the first time under sub-Doppler molecular beam conditions. A calibration procedure using the I2 standard in the visible yielded an absolute frequency accuracy of 0.02 cm–1. The obtained H2 transition frequencies provide a calibration standard in the extreme ultraviolet wavelength region. 相似文献
55.
The interaction of cyanamide with -ketocarboxylic esters in the presence of Ni(acac)2 affords N-unsubstituted aminals of acyl(alkoxycarbonyl)ketenes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 419–421, February, 1993. 相似文献
56.
Ni/γ—Al2O3,Ni/MgO,Ni/SiO2催化剂上甲烷与二氧化碳重整反应的研究 总被引:14,自引:2,他引:14
采用XRD,UV-DRS,XPS,TPR,H2-O2滴定和吡啶吸附-红外光谱等技术,研究了负载于具有不同酸碱性的γ-Al2O3,SiO2,Mgo载体上的镍催化剂表面物理化学性质,及其对甲烷与二氧化碳重整制取合成气反应催化活性的影响。结果表明,在上述负载型镍催化剂上,影响重整反应活性和积炭量的主要原因不是催化剂表面酸碱性,而是金属镍在催化剂表面的分散度。 相似文献
57.
Rapid dissolution procedure for base-metals-bearing complex materials for quality control assessment
A less labour-intensive method, involving a mixture of 1.0 g MnO2 + 20 mL HCl (11), is proposed for decomposing seven ores and six metallurgical products for accurate and precise estimation of copper, lead, zinc, cobalt and nickel for quality control assessment. Twentyone international reference materials were also analysed. Results of regression analyses are presented and intermethod comparison studies reveal that the probability of results being different compared with a reference method was less than 1%. Sample decomposition is straightforward and the method has been found to be very simple, rapid and easily adaptable, as it involves no separation of the analyte from the matrix elements. 相似文献
58.
Tubular halloysite can be used as a template to fabricate a novel metallized ceramic microstructure through electroless plating. Reduction of Pd ions by methanol is conducted to initiate Ni plating. There is a simultaneous deposition of Ni nanoparticles on the outer surface and discontinuous wires in the lumen site of the halloysite template obtained. The different deposition could be caused by the different composition distribution of ferric oxide impurity in the wall due to the isomorphic substitution during the formation of halloysite template. Its magnetic property is mainly attributed to the Ni nanoparticles, not the wires. The metallized ceramic microstructure has the potential to be utilized as a novel magnetic material. 相似文献
59.
液—液萃取浮选法分离Ni(Ⅱ),Co(Ⅱ),Fe(Ⅲ)的研究 总被引:8,自引:4,他引:8
研究了在(NH4)2SO4存在下,乙醇与水分相的条件。试验表明,丁二酮肟与镍生成的螯合物沉淀可以被萃取浮选在乙醇与水两相之间,钴与丁二酮肟生成的螯合物被乙醇萃取,Fe(Ⅲ)留在水相中,实现了同一体系中三相分离Ni(Ⅱ),Co(Ⅱ),Fe(Ⅲ),结果满意。 相似文献
60.
非晶态镍磷—镍钨磷双层组合镀层的耐蚀性能研究 总被引:2,自引:0,他引:2
本文对比研究了镍磷镀层、镍钨磷镀层及非晶态镍磷和镍钨磷双层组合镀层的耐蚀性能,分别进行了各种镀层的浸渍腐蚀实验,镀层的X射线衍射图象、镀层的扫描电镜图象、以及在工厂实际的腐蚀环境里进行的腐蚀实验。实验结果表明镍磷及镍钨磷双层组合镀层的耐 性优于镍磷镀层、镍钨磷镀层的耐蚀性。 相似文献