ChemInform Abstract: THE DISSOLUTION OF CUPRIC HYDROXIDE FILMS FROM COPPER SURFACES

1978 ◽  
Vol 9 (10) ◽  
Author(s):  
D. W. SHOESMITH ◽  
W. LEE
1977 ◽  
Vol 22 (12) ◽  
pp. 1411-1417 ◽  
Author(s):  
D.W. Shoesmith ◽  
W. Lee

1986 ◽  
Vol 47 (C8) ◽  
pp. C8-487-C8-490
Author(s):  
M. D. CRAPPER ◽  
C. E. RILEY ◽  
D. P. WOODRUFF

1975 ◽  
Vol 29 (6) ◽  
pp. 496-500 ◽  
Author(s):  
D. Kember ◽  
N. Sheppard

Infrared emission spectra from metal samples with oxide surface layers are shown to be very advantageously studied using the spectrum-ratioing facility of a recording infrared interferometer. The emission from a given sample is ratioed against that from a black-body emitter at the same temperature so as to give emittance as a function of wavenumber directly. This method has very useful application to irregularly shaped metal emitters. In the absence of selective reflection there is a direct correspondence between emission and absorption spectra for thin layers of an emitting substance. However, the presence of selective reflection leads to reduced emission and to considerable differences in the appearance of “absorption” and emission spectra in regions of strong absorption. Emission spectra obtained from copper plates heated, above 150°C, for different periods in air are shown clearly to indicate the presence of cuprous, Cu(I), and cupric, Cu(II), oxides in the surface layer.


2021 ◽  
Vol 202 ◽  
pp. 111656
Author(s):  
Luis Caro-Lara ◽  
Esteban Ramos-Moore ◽  
Ignacio T. Vargas ◽  
Magdalena Walczak ◽  
Christian Fuentes ◽  
...  

2019 ◽  
Vol 60 ◽  
pp. 124-141 ◽  
Author(s):  
Naser Ali ◽  
Joao Amaral Teixeira ◽  
Abdulmajid Addali

This research investigates the effect of surface roughness, water temperature, and pH value on the wettability behaviour of copper surfaces. An electron beam physical vapour deposition technique was used to fabricate 25, 50, and 75 nm thin films of copper on the surface of copper substrates. Surface topographical analysis, of the uncoated and coated samples, was performed using an atomic force microscopy device to observe the changes in surface microstructure. A goniometer device was then employed to examine the surface wettability of the samples by obtaining the static contact angle between the liquid and the attached surface using the sessile drops technique. Waters of pH 4, 7, and 9 were employed as the contact angle testing fluids at a set of fixed temperatures that ranged from 20°C to 60°C. It was found that increasing the deposited film thickness reduces the surface roughness of the as-prepared copper surfaces and thus causing the surface wettability to diverge from its initial hydrophobic nature towards the hydrophilic behaviour region. A similar divergence behaviour was seen with the rise in temperature of water of pH 4, and 9. In contrast, the water of pH 7, when tested on the uncoated surface, ceased to reach a contact angle below 90o. It is believed that the observed changes in surface wettability behaviour is directly linked to the liquid temperature, pH value, surface roughness, along with the Hofmeister effect between the water and the surface in contact.


1993 ◽  
Vol 20 (1) ◽  
pp. 44-49 ◽  
Author(s):  
N. L. Powell

Abstract Foliar application of manganese and boron mixed with pesticides in water solution is a common practice for peanut (Arachis hypogaea L.) production. This study was conducted to determine the compatibility of mixing manganese, boron, and leafspot fungicides using water from three sources. Spray mixtures of the chelated manganese salt of ethylene diamine tetra-acetate and the inorganic salts of manganese as manganese sulfate(TECMANGAMTM), manganese sulfate monohydrate, manganese chloride, and manganese nitrate were developed using deep-well water, shallow well water, or distilled water. Boron was added to these mixtures using boric acid or disodium octaborate tetrahydrate. In addition, all combinations were mixed with the leafspot fungicides chlorothalonil or cupric hydroxide plus sulfur. Mixtures were equivalent to recommended rates of manganese, boron, and fungicide applied to the foliage in 140 L ha-1 of spray volume. Measurements were made of solution pH and manganese remaining in solution after filtration. Development of precipitates was noted. In the deep-well water solution (pH = 8.0), addition of manganese sulfate, manganese sulfate monohydrate and manganese chloride caused precipitates to form. Manganese nitrate and chelated manganese solutions did not form precipitates. Addition of disodium octaborate tetrahydrate increased the tank-mix pH for all waters source, and caused increased precipitation of the manganese inorganic salts, but not the chelated manganese. Use of boric acid in the water lowered solution pH, and all manganese sources remained in solution. Spray-tank-mix pH was critical in keeping all manganese inorganic salts in solution. For all pH levels studied (pH 4.6 to 8.4) the chelated manganese remained in solution without formation of a precipitate. Chemical analyses of the filtrate showed that only 75 to 80% of the inorganic salts of manganese remained in solution with disodium octaborate tetrahydrate, while 100% of the chelated manganese salt remained in solution. Inorganic salts of manganese and disodium octaborate tetrahydrate should not be mixed with chlorothalonil, and none of the manganese materials should be mixed with cupric hydroxide plus sulfur as a spray-tank-mixture for foliar application.


2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Jinsub Kim ◽  
Seongchul Jun ◽  
Jungho Lee ◽  
Juan Godinez ◽  
Seung M. You

The effect of surface roughness on the pool boiling heat transfer of water was investigated on superhydrophilic aluminum surfaces. The formation of nanoscale protrusions on the aluminum surface was confirmed after immersing it in boiling water, which modified surface wettability to form a superhydrophilic surface. The effect of surface roughness was examined at different average roughness (Ra) values ranging from 0.11 to 2.93 μm. The boiling heat transfer coefficients increased with an increase in roughness owing to the increased number of cavities. However, the superhydrophilic aluminum surfaces exhibited degradation of the heat transfer coefficients when compared with copper surfaces owing to the flooding of promising cavities. The superhydrophilic aluminum surfaces exhibited a higher critical heat flux (CHF) than the copper surfaces. The CHF was 1650 kW/m2 for Ra = 0.11 μm, and it increased to 2150 kW/m2 for Ra = 0.35 μm. Surface roughness is considered to affect CHF as it improves the capillary wicking on the superhydrophilic surface. However, further increase in surface roughness above 0.35 μm did not augment the CHF, even at Ra = 2.93 μm. This upper limit of the CHF appears to result from the hydrodynamic limit on the superhydrophilic surface, because the roughest surface with Ra = 2.93 μm still showed a faster liquid spreading speed.


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