Copper spectrum

PEEK on Copper(O). PEEK is thermally stable on metallic copper under vacuum. Upon heating to temperatures in excess of 350 C, metallic copper does not induce significant changes in the PEEK/copper spectra (Figures 4-6). Those changes that occur between 30-200 C can be attributed to the desorption of contaminants and the conversion of Cu(I) to Cu(0). The Cu(I) is present because of a short exposure (3-4 min) to the laboratory environment between Xe+ etching and spin casting. Above 200°C, the spectra indicate only PEEK and Cu(0) are present. 

Fig. 11. Fourier backtransformed copper spectra. Steps of Fig. 9. Note that the splitted peak (c) results in a node of a beat at 220 eV, showing an exact compensation between the oxygen and sulfur contributions to the complex backscattering amplitude...

Figure 4.4 A comparison of angular dispersion between two analyzing crystals. The left-hand side of the figure is the Cu K line spectrum taken with a LiF(200) crystal. The right-hand copper spectrum was acquired with a KAP crystal.

The percentage of the peak area in the 580 to 620 nm range at full reduction is plotted vs the redox potential. The absorbance change in the "-copper" spectrum is expressed as a percentage of the "+ copper" spectrum. The spectra were recorded at room temperature. The protein content of both samples was 6 mg.ml" . ... 

On heating the pentahydrate, four molecules of water are lost fairly readily, at about 380 K and the fifth at about 600 K the anhydrous salt then obtained is white the Cu " ion is now surrounded by sulphate ions, but the d level splitting energy does not now correspond to the visible part of the spectrum, and the compound is not coloured. Copper(Il) sulphate is soluble in water the solution has a slightly acid reaction due to formation of [CufHjOijOH] species. Addition of concentrated ammonia... 

Figure 2.4. UV-vis absorption spectrum of 2.4e in water at concentrations of copper(Il)nitrate varying between 0 and 10 mM.

The equilibrium constants obtained using the metal-ion induced shift in the UV-vis absorption spectrum are in excellent agreement with the results of the Lineweaver-Burke analysis of the rate constants at different catalyst concentrations. For the copper(II)ion catalysed reaction of 2.4a with 2.5 the latter method gives a value for of 432 versus 425 using the spectroscopic method. 

Unfortunately, addition of copper(II)nitrate to a solution of 4.42 in water did not result in the formation of a significant amount of complex, judging from the unchanged UV-vis absorption spectrum. Also after addition of Yb(OTf)3 or Eu(N03)3 no indications for coordination were observed. Apparently, formation of a six-membered chelate ring containing an amine and a ketone functionality is not feasible for these metal ions. Note that 4.13 features a similar arrangement and in aqueous solutions, likewise, does not coordinate significantly to all the Lewis acids that have been... 

The aromatic shifts that are induced by 5.1c, 5.If and S.lg on the H-NMR spectrum of SDS, CTAB and Zn(DS)2 have been determined. Zn(DS)2 is used as a model system for Cu(DS)2, which is paramagnetic. The cjkcs and counterion binding for Cu(DS)2 and Zn(DS)2 are similar and it has been demonstrated in Chapter 2 that Zn(II) ions are also capable of coordinating to 5.1, albeit somewhat less efficiently than copper ions. Figure 5.7 shows the results of the shift measurements. For comparison purposes also the data for chalcone (5.4) have been added. This compound has almost no tendency to coordinate to transition-metal ions in aqueous solutions. From Figure 5.7 a number of conclusions can be drawn. (1) The shifts induced by 5.1c on the NMR signals of SDS and CTAB... 

Whereas ATR spectroscopy is most commonly applied in obtaining infrared absorption spectra of opaque materials, reflection-absorption infrared spectroscopy (RAIRS) is usually used to obtain the absorption spectrum of a thin layer of material adsorbed on an opaque metal surface. An example would be carbon monoxide adsorbed on copper. The metal surface may be either in the form of a film or, of greaf imporfance in fhe sfudy of cafalysfs, one of fhe parficular crysfal faces of fhe mefal. 

Figure 3 Positive-ion mass spectrum acquired from defective sampie. intense copper ion signals are observed iM/Z = 63 and 65).

Figure 4 Positive-ion mass spectrum acquired from the contact region of a control sample. Copper ion signals are absent.

Fig. 2.7. Wide-scan spectrum from almost clean copper using Al Ka radiation.

Fig. 2.15. Comparison of the Cu 2p3 2 and satellite XPS spectra from several copper compounds with the spectrum from the superconducting oxide YBajCujOj [2.76],...

Ba 4d spectrum also changes by increasing in intensity and conforming mostly to that expected of a barium silicate. As a result of the latter changes the superconducting properties of the film were destroyed. The Y 3d and Cu 2p spectra establish that yttrium and copper oxides are also formed. 

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]. 

In the I.R. spectrum of pAANa, which is shown in Table 5, the absorption bands characteristic of the carboxylate group (- 00"), the covalent sulphate group (—O—SO2—O—), and the hydroxyl group (—OH) are due to the —COONa interaction with copper sulphate according to the following mechanisms ... 

The XPS S(2p) core level spectra recorded during the stepwise deposition of copper onto poly(3-hcxyllhiophenc), or P3HT [88] are shown in Figure 5-17. The S(2p) spectrum at the lop correspond to the pristine system. On increasim copper... 

Lines in an unknown spectrum may be identified by comparing them with those on a spectrum containing a number of lines of known wavelengths. This may be performed either by comparison with charts of spectra of metallic elements such as iron or copper, or by the use of R.U. powder (see Section 20.4). 

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.

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