Nickel spectra

Native platinum frequently contains traces of nickel, as evidenced by the spectrochemical examination of specimens from Russia, Spain, and America. A sample from Kitlim,1 for example, contained 0-1 per cent, of nickel or more.8 Only one previous analysis of platinum appears to have been recorded, containing nickel, namely, a magnetic platinum from Nizhne-Tagilsk, in which 0-75 per cent, of nickel was present. Platinum ores rich in iron yield the most intense nickel spectrum. 

Four, rather different types of calculation have been performed. The first is due to Doyen and Ertl (55), who use an Anderson model including overlap and consider in their treatment only the coupling of the 2n and 5other approaches which do not have these restrictions predict the inclusion of the In and 4 ci orbitals of CO and of the s-band of nickel to be essential for an understanding of the bonding. Thus it is unlikely that such a calculation can be used to explain the CO/nickel spectrum until the other orbitals are included. 

The rich nickel spectrum in the vicinity of the most sensitive atomic absorption Ni line, 232.00 nm, leads to pronounced curvature of the calibration graph. For highest sensitivity and somewhat reduced calibration curvature, a 0.2 nm or less spectral bandpass must be employed to attempt to isolate the 232.00 nm line from adjacent non-absorbing Ni lines at 231.72nm and 232.14nm. 

Fig. Vni-12. Energy spectrum of Ne" ions that are scattered over 90° by a halogenated nickel surface. The incident energy of the ions is 300 V. (From Ref. 92.)...

When levuhnic acid (CH3CCH2CH2CO2H) was hydrogenated at high pressure over a nickel catalyst at 220°C a single product C5Hg02 was isolated in 94% yield This compound lacks hydroxyl absorption in its IR spectrum and does not immediately liberate carbon dioxide on being shaken with sodium bicarbonate What is a reasonable structure for the compound" ... 

The neutron dose to graphite due to irradiation is commonly reported as a time integrated flux of neutrons per unit area (or fluence) referenced to a particular neutron energy. Neutron energies greater that 50 keV, 0.1 MeV, 0.18 MeV, and 1 MeV were adopted in the past and can be readily foimd in the literature. In the U.K., irradiation data are frequently reported in fluences referenced to a standard flux spectrum at a particular point in the DIDO reactor, for which the displacement rate was measured by the nickel activation [ Ni(np) t o] reaction [equivalent DIDO nickel (EDN)]. Early on, neutron irradiation doses to the graphite moderator were reported in terms of the bum-up (energy extracted) from imit mass of the adjacent nuclear fuel, i.e., MW days per adjacent tonne of fuel, or MWd/Ate. 

When PMMA was adsorbed onto an iron substrate, four components were not sufficient to explain the C(ls) spectrum (see Fig. 21b) and a fifth component had to be added at 288.1 eV as shown in Fig. 21c. This component was attributed to carboxyl groups, indicating that the ester groups were partially hydrolyzed. Similarly, Leadley and Watts found that there were five components in the C(ls) spectrum of PMMA spin-coated onto aluminum, copper, and nickel substrates 124]. 

The spectrum from a Coolidge tube often contains lines traceable to impurities, those of copper, nickel, and iron being the most common. The impurities may be present in the target of the new tube, but they are more likely to be deposited on the target during operation. It is consequently desirable that the analytical chemist maintain current acquaintance with the spectrum of his x-ray source. 

Fig. 4-3. Lines from copper, nickel, and iron impurities which appeared in the spectrum of an x-ray tube after the tube had been operated for several hundred hpurs. X-rays from the tube were scattered by filter paper in the sample holder.

Unfortunately, filtering is not generally so effective. Figure 4-4a shows what can be accomplished by use of a nickel filter 0.01 mm thick oil a spectrum with intensity independent of wavelength. 

Background spectrum, tungsten, copper, and nickel lines in, 229 Backlash, error due to, 285-287 Bank notes, histograms from x-ray spec-trographic chart recordings of, 225-227... 

Some data have been obtained on the activity of the catalyst in a reduced state [for nickel (141,143,144), palladium (144°), and molybdenum (145, 145a). In the case of nickel catalysts the formation of nickel in the zero oxidation state takes place during the reduction of the surface organometallic compound by H2. The infrared spectrum shows the total restoration of the concentration of Si—OH groups (139), so the reduction proceeds according to the scheme ... 

Newton s second law, L0 nickel, 49, 665 nickel arsenide structure, 201 nickel surface, 189 nickel tetracarbonyl, 665 nickel-metal hydride cell, 520 NiMH cell, 520 nitrate ion, 69, 99 nitration, 745 nitric acid, 629 nitric oxide, 73, 629 oxidation, 549 nitride, 627 nitriding, 208 nitrite ion, 102 nitrogen, 120, 624 bonding in, 108 configuration, 35 photoelectron spectrum, 120... 

Figure 4-7. Spectrum of a typical, octahedral nickel(ii) complex.

Fig. 12. Mossbauer spectrum of an argon matrix containing iron and nickel (59).

P 12] A falling film micro reactor was applied for generating thin liquid films [6]. A reaction plate with 32 micro channels of channel width, depth and length of 600 pm, 300 pm and 66 mm, respectively, was used. Reaction plates made of pure nickel and iron were employed. The micro device was equipped with a quartz window transparent for the wavelength desired. A 1000 W xenon lamp was located in front of the window. The spectrum provided ranges from 190 to 2500 nm the maximum intensity of the lamp is given at about 800 nm. 

In contrast to 4, 2-acetylpyridine iV-methylthiosemicarbazone, 3a, formed yellow-green, paramagnetic, octahedral [Ni(3a)2A2] complexes with nickel(II) chloride and bromide. The neutral form of the ligand was proposed to be NN eoordinated [180]. Brown, paramagnetic [Ni(3a-H)2] was prepared from nickel(II) acetate with NNS coordination, and its d-d spectrum and ligand field... 

They found that the order for the M—0 stretching modes (M—0 force constants) was (02)Pd(02) > Pd(Oj) and (02)Ni(02) > Ni(02), and since the 0-0 force constant increased as the M-0 force constant decreased, reversibility could not be equated with shorter 0—0 bond length. To test the proposed isosceles model they predicted the various absorptions that would be expected on the basis of the symmetrical structure (a) and unsymmetrical structure (c), Fig. 8. If the isotopic ratio of 0 0 is 1 1, then three bands would be expected for structure (a), with relative intensities 1 2 1, and four bands would be expected for structure (c), with relative intensities 1 1 1 1, the two oxygen atoms now being in different environments. These workers 189) then obtained the IR spectrum for the cocondensation product from the reaction between nickel and O2 (4.2—10°K), in isotopic ratio 0 =1 1, and found three bands with relative inten-... 

Fig. 7.10 Ni Mossbauer spectra of LaNi5 samples after various treatments (a) no hydrogen exposure, (b) activated in hydrogen, (c) after 1,584 thermally induced absorption-desorption cycles, as described in the text. The solid lines are least-squares fits to a single Lorentzian in (a) and (b). (c) was fitted with a single Lorentzian (representing nonmagnetic nickel atoms) and a 12-line hyperfine spectrum (from [20])...

The first Ni Mossbauer spectrum of nickel in a bioinorganic compound with determinable EFG and isomer shift was reported for a nickel complex compound with planar [NiSJ core and considered as a model compound for hydrogenase. This Mossbauer spectrum from the formal Ni compound is presented in Fig. 7.16. The observed quadrupolar interaction can be understood in terms of ligand field theory. In this approach, the b g and levels (d y2 and d ) are not occupied which is expected to cause a large negative EFG contribution [32]. 

Fig. 7.16 Ni Mossbauer spectrum at 4.2 K of a nickel complex compound with planar [NiS4] core known as a model compound for hydrogenase (source Nio.gsCro.is (97% enriched) activated at Mainz Microtron) (from [32])...

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