Carbon load

Loaded Adsorbents. Where highly efficient removal of a trace impurity is required it is sometimes effective to use an adsorbent preloaded with a reactant rather than rely on the forces of adsorption. Examples include the use of 2eohtes preloaded with bromine to trap traces of olefins as their more easily condensible bromides 2eohtes preloaded with iodine to trap mercury vapor, and activated carbon loaded with cupric chloride for removal of mercaptans. 

A continuous polymer anode system has been developed specifically for the cathodic protection of buried pipelines and tanks. The anode, marketed under the trade name Anodeflex , consists of a continuous stranded copper conductor (6AWG) which is encased in a thick jacket of carbon-loaded polymer, overall diameter 12-5 mm. To prevent unintentional short circuits an insulating braid is sometimes applied to the outer surface of the conductive polymer. 

A conductive polymer electrode has been designed specifically for the cathodic protection of steel reinforcing bars in concrete and is marketed under the trade name Ferex . The anode consists of a 16 AWG stranded copper conductor surrounded by a carbon-loaded polymeric coating similar to that used on the Anodeflex system ) to provide a nominal anode diameter of 8 mm The manufacturer claims that at the maximum recommended current density of 0 08 Am the anode life in concrete will be 32 years with a proportionately longer life at lower current densities. 

In their earlier work, Modes et al. [53] described low polarization electrodes composed of Teflon-bonded high surface area carbon, loaded with different electrocatalysts (Pt, platinized Pt, Co, Ni). The best results were obtained by using cobalt... 

Binders (TbC) 671 Bipolar pulse conductivity detector (LC) 588 Bonded phases (GC) 125 crosslinked 126 estersils 125 nonextractable 126 siloxane 125 Bonded phases (LC) 324 carbon loading 335 cleavage of ligands 336 eluotropic strength (LSC) 382 endcapping 326 hydrophobicity 364 metal impurities 369 models for surface 337 physical characteristics 333, 366... 

Manufacturer Derivatizing Reagent Percent Silanol Groups Reacted Carbon Loading ( ) Average Particle Size ( )... 

Figures 10 and 11 show the structure of the hindered phenolic antioxidant Irganox 1010 (Ciba) and its negative ion APCI mass spectra, respectively. Separation was achieved under the following LC conditions Column Aqua Cl 8 (Phenomenex) 3 pm, 150x2.00 mm, 15% carbon loading, proprietary end capping. Column Temp 50°C. Injection volume 5 pi.

These findings suggest that a prerequisite for the successful continuous operation of bioreactors for azo-dye conversion is the thorough control of carbon loading the azo-dye conversion degree drops to vanishing levels if carbon depletion occurs. 

A similar study has been carried out in order to test the capacity of RP-HPLC for the authenticity test of chilli powders on the basis of pigment composition. Carotenoid pigments were extracted by shaking 3 g of chilli powder with 10 ml of acetone for 30 min. The supernatant was decanted and the procedure was repeated as the solid rest was nearly colourless. The collected organic phases were evaporated and redissolved in the mobile phase. Separations were performed on a narrow-bore ODS column (150 X 2 mm i.d., carbon loading, 9.5 per cent). Eluents A and B were methanol-ACN (80 20, v/v) and bidistilled water, respectively. Gradient elution was initiated by 15 per cent A increased to 80 per cent A in 25 min, held for 10 min, increased to 90 per cent A in 10 min, held for 10 min, increased to 97 per cent A in 3 min and held for 62 min. Each step of gradient elution was linear. Measurements were... 

Figure 3.11 Comparison of the retention of toluene to decylbenzene as a measure of hydrophobicity of different octadecyl-bonded silica gels with different carbon loadings. Columns , LOC-ODS-E O, LOC-ODS-NE O, HIC-ODS-E A, HIC-ODS-NE eluent, 80% aqueous acetonitrile at 30 °C. Compounds. 1, toluene 2, nonylbenzene.

Another approach to preparing a stable reversed phase with fewer residual silanols is the use of polyfunctional silanes of the type R2SiX2. These react to form a polymeric stationary phase that shields the siloxane bonds and restricts access to residual silanols. Polymer phases have higher carbon loads and are typically more retentive than monomeric phases. However, they are more difficult to synthesize reproducibly and may exhibit batch-to-batch variability in their properties. They also exhibit poorer mass transfer kinetics and so provide poorer efficiency than monomeric phases. 

The carbon or silica-loaded nanoparticles were treated in a tube-furnace under controlled temperature and atmosphere. A typical protocol involved shell removal by heating at 300°C under 20% O2/N2 for 1 h and calcination at 400°C under 15% H2/N2 for 2 h. The carbon-loaded Au or AuPt nanoparticles are denoted as Au/C or AuPt/C. The silica-loaded AuPt nanoparticles are denoted as AuPt/Si02. 

Bonding density (or surface coverage) for a stationary-phase is calculated from the percent carbon loading, substrate surface area, and estimated relative molecular... 

The most common approach to chromatographic stationary-phase characterization is in terms of bulk-phase properties, such as percent carbon loading onto the silica substrate. This property together with the surface area of the substrate and the molecular characteristics of the bonded silane can be used to calculate the bonding density (A) of the chromatographic sorbent [60] ... 

The most widely used support substance for the manufacture of packing materials in analytical HPLC columns is silica. Silica can be treated with organochlorosilanes or similar reagents to produce siloxane linkages of any derived polarity similar to what is done for GC columns (stationary phases). The most popular materials are octadecyl silane (ODS), which contains a carbon loading of CIS groups and octyl, which contains C8 groups materials such C2, C6, and C22 are also available. 

Column Particle size ( lm) Length (mm) ID (mm) Pore size (A) Surface area (mVg) Carbon load (%) End capping pH range... 

In addition to the way in which the MPL is manufactured, other MPL parameters directly affect fuel cell performance. These include fhickness of fhe MPL, carbon loading, PTFE content, type of carbon parficles, efc. The following subsection will briefly discuss them. 

Figure 4.19 shows results by Park, Lee, and Popov [155] for the effect of carbon loading in the MPL on fuel cell performance. It can also be seen that a fuel cell without an MPL performs very poorly compared to the others. Jian-hua et al. [137] recently presented very similar results. 

Polarization citrve for PEMFCs with two different cathode diffusion layers carbon fiber paper with one MPL and carbon fiber cloth with two MPLs. Operating conditions ceU temperature of 85°C, O2/H2 dewpoint temperatures of 90/100°C gas pressures of 2 atm. CFP DL was a TGP-H-090 with 20 wt% PTFE in the MPL. CCs were PWB-3 from Stackpole cathode CC had 15 wt% PTFE in the MPL near the CL and 30 wt% PTFE in the MPL near the flow field. The anode CC had 15 wt% PTFE in both MPLs carbon loading on the MPL was not specified. The catalyst Pt loading was 0.4 mg cm and the Nation loading was 1.1 mg cm for all catalyst layers the membrane was a Nation 115. (Modified from E. Antolini et al. Journal of Power Sources 163 (2006) 357-363. With permission from Elsevier.)... 

S. Park, J. W. Lee, and B. N. Popov. Effect of carbon loading in microporous layer on PEM fuel cell performance. Journal of Power Sources 163 (2006) 357-363. 

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