scholarly journals Topographic Analysis of Calcite (104) Cleavage Surface Dissolution in Ethanol–Water Solutions

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 376
Author(s):  
Shaoxiong Ye ◽  
Pan Feng ◽  
Jiaping Liu
Keyword(s):  
Organic Molecules ◽  
Volume Fraction ◽  
Ultrapure Water ◽  
Cleavage Surface ◽  
Etch Pits ◽  
Topographic Analysis ◽  
Water Solutions ◽  
Topographic Features ◽  
Fundamental Understanding

The interaction of organic molecules with calcite surfaces plays a key role in many geochemical, industrial and biomineralization processes, and exploring the influences of organic molecules on calcite reactions is crucial for a fundamental understanding of the reaction mechanisms. Here, we used digital hologram microscopy to explore the in situ evolution of the calcite (104) surfaces when dissolved in ethanol–water solutions, and total organic carbon analysis was applied to confirm the adsorption of ethanol by calcite. The results showed that the bulk dissolution rate of calcite decreases as the volume fraction of ethanol increases, and the topographic features of etch pits were also altered by the presence of ethanol. When exposed to too much ethanol, the etch pits’ growth was inhibited and their shapes tended to change from rhombuses in ultrapure water to triangles. Our results provide insights into the interaction between adsorbed ethanol and evolving calcite crystal, which highlights the dissolution regulation of calcite by organic molecules that could benefit a broad range of fields.

SREM observation of the interaction between the in-situ deposited Pd small particles and MgO cleavage surface

1986 ◽  
Vol 44 ◽  
pp. 382-383
Author(s):  
H.-J. Ou
Keyword(s):  
Electron Microscopy ◽  
Small Particle ◽  
Small Particles ◽  
Cleavage Surface ◽  
Metallic Particles ◽  
Microscopy Technique ◽  
Ceramic Surfaces ◽  
Reflection Electron Microscopy ◽  
New Perspective

The understanding of the interactions between the small metallic particles and ceramic surfaces has been studied by many catalyst scientists. We had developed Scanning Reflection Electron Microscopy technique to study surface structure of MgO hulk cleaved surface and the interaction with the small particle of metals. Resolutions of 10Å has shown the periodic array of surface atomic steps on MgO. The SREM observation of the interaction between the metallic particles and the surface may provide a new perspective on such processes.

scholarly journals Safe and Effective Use of Ozone as Air and Surface Disinfectant in the Conjuncture of Covid-19

Gases ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 19-32
Author(s):  
Elena Grignani ◽  
Antonella Mansi ◽  
Renato Cabella ◽  
Paola Castellano ◽  
Angelo Tirabasso ◽  
...  
Keyword(s):  
Organic Molecules ◽  
Scientific Literature ◽  
Toxic Substance ◽  
Health And Safety ◽  
Emergency Situation ◽  
Ambient Air ◽  
Public Places ◽  
Safety Measures ◽  
Effective Use

The present paper extrapolates quantitative data for ozone virucidal activity on the basis of the available scientific literature data for a safe and effective use of ozone in the appropriate cases and to explore the safety measures developed under the stimulus of the current emergency situation. Ozone is a powerful oxidant reacting with organic molecules, and therefore has bactericidal, virucidal, and fungicidal actions. At the same time, it is a toxic substance, having adverse effects on health and safety. Its use is being proposed for the disinfection of workplaces’ and public places’ atmosphere, and for disposable masks and personal protective equipment disinfection for reuse, with particular reference to the COVID-19 pandemic outbreak. Ozone can be generated in situ by means of small, compact ozone generators, using dried ambient air as a precursor. It should be injected into the room that is to be disinfected until the desired ozone concentration is reached; after the time needed for the disinfection, its concentrations must be reduced to the levels required for the workers’ safety. The optimal use of ozone is for air and surface disinfection without human presence, using a concentration that is effective for the destruction of viruses, but not high enough to deteriorate materials.

Macroscopical monolayer films of ordered arrays of gold nanoparticles as SERS substrates for in-situ quantitative detection in aqueous solutions

Nanoscale ◽  
2021 ◽  
Author(s):  
Lixiang Xing ◽  
Cui Wang ◽  
Yi Cao ◽  
Jihui Zhang ◽  
Haibing Xia
Keyword(s):  
Gold Nanoparticles ◽  
Volume Fraction ◽  
Water Volume ◽  
Quantitative Detection ◽  
Monolayer Films ◽  
Au Nps ◽  
Sers Substrates ◽  
Ordered Arrays ◽  
Water Volume Fraction

In this work, macroscopical monolayer films of ordered arrays of gold nanoparticles (MMF-OA-Au NPs) are successfully prepared at the interfaces of toluene-diethylene glycol (DEG) with a water volume fraction of...

scholarly journals Sulfur bacteria promote dissolution of authigenic carbonates at marine methane seeps

2021 ◽  
Author(s):  
Dalton J. Leprich ◽  
Beverly E. Flood ◽  
Peter R. Schroedl ◽  
Elizabeth Ricci ◽  
Jeffery J. Marlow ◽  
...  
Keyword(s):  
Carbonate Rocks ◽  
Sulfur Oxidation ◽  
Methane Seeps ◽  
Etch Pits ◽  
Active Dissolution ◽  
Authigenic Carbonates ◽  
Sulfur Bacteria ◽  
Sulfur Oxidizing ◽  
Sulfur Oxidizing Bacteria

AbstractCarbonate rocks at marine methane seeps are commonly colonized by sulfur-oxidizing bacteria that co-occur with etch pits that suggest active dissolution. We show that sulfur-oxidizing bacteria are abundant on the surface of an exemplar seep carbonate collected from Del Mar East Methane Seep Field, USA. We then used bioreactors containing aragonite mineral coupons that simulate certain seep conditions to investigate plausible in situ rates of carbonate dissolution associated with sulfur-oxidizing bacteria. Bioreactors inoculated with a sulfur-oxidizing bacterial strain, Celeribacter baekdonensis LH4, growing on aragonite coupons induced dissolution rates in sulfidic, heterotrophic, and abiotic conditions of 1773.97 (±324.35), 152.81 (±123.27), and 272.99 (±249.96) μmol CaCO3 • cm−2 • yr−1, respectively. Steep gradients in pH were also measured within carbonate-attached biofilms using pH-sensitive fluorophores. Together, these results show that the production of acidic microenvironments in biofilms of sulfur-oxidizing bacteria are capable of dissolving carbonate rocks, even under well-buffered marine conditions. Our results support the hypothesis that authigenic carbonate rock dissolution driven by lithotrophic sulfur-oxidation constitutes a previously unknown carbon flux from the rock reservoir to the ocean and atmosphere.

Passivation of Si surfaces by hydrogen and organic molecules investigated by in-situ photoluminescence techniques

2010 ◽  
Vol 7 (2) ◽  
pp. 210-213 ◽  
Author(s):  
Joerg Rappich ◽  
Xin Zhang ◽  
Sébastien Chapel ◽  
Guoguang Sun ◽  
Karsten Hinrichs
Keyword(s):  
Organic Molecules

Molecular Grafting on Si(111) Surfaces: An Electrochemical Approach

1996 ◽  
Vol 451 ◽  
Author(s):  
C. Henry de Villeneuve ◽  
J. Pinson ◽  
F. Ozanam ◽  
J. N. Chazalviel ◽  
P. Allongue
Keyword(s):  
Aqueous Solution ◽  
Electrochemical Method ◽  
Organic Molecules ◽  
Diazonium Salts ◽  
Molecular Films ◽  
Electrochemical Approach ◽  
The Stability ◽  
Structural Characterizations ◽  
Direct Attachment

ABSTRACTThis works addresses the question of the direct attachment of organic molecules on Si(111) by an electrochemical method. Anodic grafting of -OR group is demonstrated by in-situ STM and the LDOS characterized. The grafting of aryl groups, by reduction of aryl diazonium salts in aqueous solution, is also described. This approach leads to well ordered and close-packed thin molecular films with various functionality. Different chemical and structural characterizations conclude to a Si-C binding, between the Si surface and aryl groups. The stability of films is also investigated.

Photocatalytic reforming of glycerol for H2 evolution on Pt/TiO2: fundamental understanding the effect of co-catalyst Pt and the Pt deposition route

2015 ◽  
Vol 3 (5) ◽  
pp. 2271-2282 ◽  
Author(s):  
Xiaoliang Jiang ◽  
Xianliang Fu ◽  
Li Zhang ◽  
Sugang Meng ◽  
Shifu Chen
Keyword(s):  
Active Sites ◽  
H2 Evolution ◽  
Co Catalyst ◽  
Fundamental Understanding

The effects of deposited Pt and its deposition route on the photocatalytic reforming of glycerol for H2 evolution over Pt/TiO2 were investigated. Intimately loaded Pt(0) particles are the key active sites for the reaction, the formation of which was favored by an in situ photo-deposition route.

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