H2SO4 solutions

Koinuma M and Uosaki K 1996 Atomic structure of bare p-GaAs(IOO) and electrodeposited Cu on p-GaAs (100) surfaces in H2SO4 solutions An AFM study J. Eiectroanai. Chem. 409 45-50... 

Acid resistance This can be checked by using N/IO (H2SO4) solution. When a few drops are spilt on the test piece, or when the test piece is dipped for almost half an hour in the solution. It should develop no corrosion spots on the surface. 

Clean metallic aluminum is extremely reactive. Even exposure to air at ordinary temperatures is sufficient to promote immediate oxidation. This reactivity is self-inhibiting, however, which determines the general corrosion behavior of aluminum and its alloys due to the formation of a thin, inert, adherent oxide film. In view of the great importance of the surface film, it can be thickened by anodizing in a bath of 15% sulfuric acid (H2SO4) solution or by cladding with a thin layer of an aluminum alloy containing 1 % zinc. 

Development of Pits in Stainless Steel inO-5 n NaCl + 0 -1 n H2SO4 Solution , Corns. Sci., 12, 925 (1972)... 

Fig. 19.16 Schematic E — I diagrams of local cell action on stainless steel in CUSO4 + H2SO4 solution showing the effect of metallic copper on corrosion rate. C and A are the open-circuit potentials of the local cathodic and anodic areas and / is the corrosion current. The electrode potentials of a platinised-platinum electrode and metallic copper immersed in the same solution as the stainless steel are indicated by arrows, (a) represents the corrosion of stainless steel in CUSO4 -I- H2 SO4, (b) the rate when copper is introduced into the acid, but is not in contact with the steel, and (c) the rate when copper is in contact with the stainless steel...

Ni single-crystal faces in HzO + HCIO4 or H2SO4 solutions have been investigated by Arold and Tamm using impedance.743 Ni (100), (110), and (111) single-crystal faces were prepared by the method described by... 

Fig. 2. Cyclic voltammograms over supported Pt (40wt.%) catalysts in H2SO4 solution at 298K (scan rate = 20mV/s).

Fig.2. Expectation time of efflorescence of (NH4)2S04 and H2SO4 solution, log(x(min)) according to ammonium-sulfate ratio (ASR) at Dpm = l, m and 25°C.

To produce amorphous VOPc, 5.0 g of crude VOPc was added into 250 ml of concentric H2SO4 solution, and then the mixture was stirred slowly at 5 °C for 2 h. After acid-treatmcait, cake was collected by filtration, washed with distilled water until washing solution became neutral, then dried at 70 °C over 24 h in a dry oven. To produce fine crystal VOPc, 5 g of amorphous VOPc was added into 90 ml of NMP/H2O solution, and then stirred slowly at 80 C for 1 h. After recrystallization, cake was collected by filtration, washed with methanol, and then dried. All polymorphs were assayed by XRD analysis. 

Observations, made by Sigler and Masters , on the exchange in 0.4 M H2SO4, solution, have led to a rate law... 

Product selectivities ( 2 mol%) (taking into account 2- and 3-etho entane only) from the reaction of 0-ethanol and S-2-pentanol ( 0) over Nafion-H and HZSM-5 catalysts at 100°C and 1 MPa and in concentrated H2SO4 solution at 100°C and 0.1 MPa, where the true inversion (I) was calculated by using the equation given above. 

FIGURE 10.8 Influence of the adsorption of organic substances (a) on the electrocapillary curve, (b) on the capacitance curve, and (c) on the plot of surface charge against potential (1) 0.1 M H2SO4 solution (2) the same, with 0.1 MC4H9OH. 

FIGURE 10.9 Galvanostatic charging curve for a platinized platinum electrode in 0.1 M H2SO4 solution (1) anodic scan, (2) cathodic scan. 

Figure 7.1 Cyclic voltamograms of Pt(l 11) electrodes modified by Bi, Sb, As, and Te deposition at intermediate coverages, as indicated, in 0.5 M H2SO4 solution. Sweep rate 50 mV/s.

Figure 7.3 Plot of the platinum (hydrogen plus anion) charge density versus the charge density associated with the adatom redox process (Bi or Te, as indicated) on a Pt(l 11) electrode in 0.5 M H2SO4 solution. Straight lines represent the expected behavior for the stoichiometry indicated in the figure.

Electrodes in 0.5 M H2SO4 Solution (Except Where Otherwise Stated). All Potentials are Given vs. RHE and Measured at 50 mV/s... 

Figure 7.4 Peak potential values of adatom redox processes on Pt(l 11) and Pt(lOO) electrodes in 0.5 M H2SO4 solution, as labeled, plotted against the enthalpy of formation of the corresponding bulk oxide. Lines are included to indicate the tendency (the full line corresponds to the filled squares, and the dashed line to the open circles).

Figure 7.5 Cyclic voltammogram of a Pt(775) electrode in 0.5 M H2SO4 solution and a hard sphere model of this surface. Sweep rate 50 mV/s. In the hard sphere model, four atoms forming the (110) step site have been identified in black.

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