MetaUic cation

Berthod et al. [325] employed countercurrent chromatography with diethyl-hexyl phosphoric acid (DEHPA) reverse micelles in heptane as a stationary phase to extract metaUic cations such as Fa +, Ce, Pr, and Nd + (lanthanide series). This technique was suggested for the application of ion filtering and concentration or for deionization of aqueous phases. Ashrafizadeh et al. [326] re-... 

Furthermore, the advantage of the Pourbaix diagram as shown in Figure 3.6a is that it predicts the electrochemical state for immunity, corrosion, and passivation, and it is related to the polarization curve shown in Figure 3.6b. However, only the polarization curve predicts the corrosion rate through the current density icorr for metal oxidation and the passivation rate through the passive current density for metaUic cation reduction to form an oxide protective film on the electrode surface. The passivation phenomenon is discussed in details in Chapter 6. 

Chromium(VI) can produce a green complex, with blue iridescence (chirally resolvable by organic and organo-metaUic cations) ... 

If pure, the carbides of Groups 1 and 2 are characterized by their transparency and lack of conductivity. The carbides of Group 3, ie. Sc, Y, the lanthanides, and the actinides, ate opaque. Some, depending on composition, show metallic luster and electroconductivity. The cation may exist in the MC2 phases of this group, and the remaining valence electron apparendy imparts pardy metaUic character to these compounds. 

The use of supports such as Ti02, where the effect of a strong metal-support interaction (SMSI) was observed at high reduchon temperature, is one of the recommended routes. It is proposed that TiO having coordinatively unsaturated Ti cations that could interact with the electron pair donor site of the C=0 bond, facilitates adsorption of the unsaturated aldehyde in a favorable way to produce UOL [74, 75]. As for the metaUic phase, both theoretical and experimental studies indicate that larger particles improve the selectivity to UOL. In effect, it has been... 

Yang ZF, Guha AK, and Sirkar KK. Simultaneous and synergistic extraction of cationic and anionic heavy metaUic species by a mixed solvent extraction system and a novel contained hquid membrane device. Indust Eng Chem Res, 1996 35(11) 4214-4220. 

Purity of the effluent to be treated organic pollution and multivalent cations must be avoided (1) EM and BPM swell in the presence of aromatic compounds and (2) metaUic hydroxides precipitate in the membranes when the divalent cation concentrations reach 1 ppm. 

A metaUic bond forms when metal cations attract freely moving, delocalized valence electrons. 

CrystaUine Ag+/norbomene (26) complexes can be prepared readily. Excitation of these at 313 nm, where only the complexes absorb, in acetonitrile solution, results in the formation of the norbomene radical cation (27). The formation of this radical cation species involves electron transfer from the alkene moiety to the silver, resulting in the formation of metaUic silver. The resultant radical cation reacts with solvent to 5deld the... 

Fig. 19.4 Schematic illustration of the mechanism of corrosion protection of metaUic substrate by different ILs containing [C4mim] cation [38]...

Deionized water has a hardness of zero. This type of water was earher produced by distillation. Today an ion-exchange technique is used. Water softeners generally have a single resin, a cationic resin, to remove calcium and magnesium ions. Deionization equipment, whidi removes all ions (metallic and non-metaUic) from the water, uses two columns, operating in series. One contains cationic resin and removes metallic ions, the other has an anionic resin to remove the add radicals. 

For an electrode containing no metaUic impurities under concentration polarization, the apphed current density must be a fraction of the hmiting current density that is, ic < it for optimizing the electrolytic deposition of cations on the cathode surface electrodes. This current density constraint is the basis for deriving eq. (7.119), which dictates that when ic — ii since... 

Salty substances exhibit a variety of pharmacological effects, whose character depends on the type of cation and anion. Some substances are toxic at higher concentrations. The compound consumed in the largest amount is sodium chloride. The daily intake of salt in developed countries is estimated at 8 15g. Sodium chloride supports the perception of taste of foods at the required intensity and fullness, stimulates not only receptors for salty taste, but significantly increases the perception of the sweet taste of sucrose and some other sweet substances, as well as sour taste perception, and suppresses the sensation of metaUic taste and some other... 

Metal nitrosyls are the transition metal complexes of nitric oxide (NO) containing a metal-nitrogen bond. Roussin s red salt, Na2[Fe2(NO)4S2], and Roussin s black salt, Na[Fe4(NO)7S3], were the earliest known metallic nitrosyls. In line with the inclusion of metal carbonyl complexes under the category of organometaUic compounds, the metallic nitrosyl complexes are also recently included in organometaUic compounds. The nitric oxide cation is isoelectronic with carbon monoxide. Hence, there is quite a bit of resemblance in the chemistry of metaUic carbonyls and nitrosyls. However, the contrasts in these chemistries are also noteworthy. 

Like polymeric electrodes, carbon can form a positive or negative electrode by virtue of doping the material with anions or cations. The ions intercalate into the stmcture of the carbon and can often be deintercalated reversibly. In addition, work on carbons for Uthium-ion type cells where essentiaUy metaUic lithium intercalates into graphitic carbons has been studied. Preliminary reports of Uthium intercalation in carbon [97,176] were... 

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