The Role of Sulfuric Acid in Continental Weathering: Insights from Dissolved major ions and inorganic carbon isotopes of the Teesta River, lower Brahmaputra system

2021 ◽  
Author(s):  
Satyabrata Das ◽  
Gyana Ranjan Tripathy ◽  
Santosh K Rai ◽  
Mohd Danish ◽  
Divya Thakur ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Carbon Isotopes ◽  
Inorganic Carbon ◽  
Major Ions ◽  
Continental Weathering

scholarly journals Assess the Effectiveness of protective Concrete coatings of microbiological sulfuric acid Aggression

2019 ◽  
Vol 97 ◽  
pp. 02022
Author(s):  
Viktor Sopov ◽  
Julia Danchenko ◽  
Ekaterina Latorez
Keyword(s):  
Sulfuric Acid ◽  
Building Structures ◽  
Predominant Role ◽  
Microbiological Processes ◽  
Repair Materials ◽  
Bactericidal Properties ◽  
Mineral Acids ◽  
Concrete Building ◽  
Modified Epoxy

Specification of corrosion processes in sewerage networks, the predominant role of microbiological processes in them requires the protection of concrete with materials resistant to specific biogenic sulfuric acid aggression. The effective protective materials, in this case, are those that, in addition to acid-proofing materials, have bactericidal properties. Polymer composite materials (PCM) of cold curing based on modified epoxy-resin, resins with dispersed oxides as fillers are widely used in construction. Unique properties and simple technologies make it possible to use them as injection formulations for repair, restoration and restoration of building structures and structures, waterproofing and facing materials, for impregnating, gluing and coating metal, wooden, brick and concrete building structures and parts. In the reconstruction and restoration of sewerage collectors operating under conditions of exposure to liquid biochemically aggressive media with mineral acids and organic substances, particular attention is paid to the permeability of repair materials. Based on the results of the study, PCM compositions were chosen whose estimated lifetime is about 20 years, ensuring reliable protection of the sewage collectors from corrosion.

scholarly journals The role of ammonia in sulfuric acid ion induced nucleation

2008 ◽  
Vol 8 (11) ◽  
pp. 2859-2867 ◽  
Author(s):  
I. K. Ortega ◽  
T. Kurtén ◽  
H. Vehkamäki ◽  
M. Kulmala
Keyword(s):  
Sulfuric Acid ◽  
Quantum Chemical ◽  
Local Minimum ◽  
Good Accuracy ◽  
Energy Surface ◽  
Ground Level ◽  
Computational Effort ◽  
Free Energy Surface ◽  
Large Clusters

Abstract. We have developed a new multi-step strategy for quantum chemical calculations on atmospherically relevant cluster structures that makes calculation for large clusters affordable with a good accuracy-to-computational effort ratio. We have applied this strategy to evaluate the relevance of ternary ion induced nucleation; we have also performed calculations for neutral ternary nucleation for comparison. The results for neutral ternary nucleation agree with previous results, and confirm the important role of ammonia in enhancing the growth of sulfuric acid clusters. On the other hand, we have found that ammonia does not enhance the growth of ionic sulfuric acid clusters. The results also confirm that ion-induced nucleation is a barrierless process at high altitudes, but at ground level there exists a barrier due to the presence of a local minimum on the free energy surface.

The role of acidity profile in the nanotubular growth of polyaniline

2010 ◽  
Vol 64 (1) ◽  
Author(s):  
Elena Konyushenko ◽  
Miroslava Trchová ◽  
Jaroslav Stejskal ◽  
Irina Sapurina
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Reaction Temperature ◽  
Subsequent Growth ◽  
Subsequent Oxidation ◽  
Ammonium Peroxydisulfate ◽  
Aniline Oligomers ◽  
Positive Effect ◽  
Granular Morphology

AbstractConditions of polyaniline (PANI) nanotubes preparation were analyzed. Aniline was oxidized with ammonium peroxydisulfate in 0.4 M acetic acid. There are two subsequent oxidation steps and the products were collected after each of them. At pH > 3, neutral aniline molecules are oxidized to non-conducting aniline oligomers. These produce templates for the subsequent growth of PANI nanotubes, which takes place preferably at pH 2–3. At pH < 2, granular morphology of the conducting PANI is obtained. High final acidity of the medium should be avoided in the preparation of nanotubes, e.g., by reducing the amount of sulfuric acid which is a by-product. Reduction of the peroxydisulfate-to-aniline mole ratio was tested for this purpose in the present study. Lowering of the reaction temperature from 20°C to −4°C had a positive effect on the formation of nanotubes.

The Role of Binary and Ion Nucleation of Sulfuric Acid and Water Vapor in the Dynamics of Sulfate Aerosol Formation in the Atmosphere

2021 ◽  
pp. 53-60
Author(s):  
A. E. Aloyan ◽  
◽  
A. N. Yermakov ◽  
V. O. Arutyunyan ◽  
◽  
...  
Keyword(s):  
Water Vapor ◽  
Sulfuric Acid ◽  
Three Dimensional ◽  
Ionization Rate ◽  
Sulfate Aerosol ◽  
Aerosol Formation ◽  
Three Dimensional Model ◽  
Aerosol Composition ◽  
Transport And Transformation

The results of one-dimensional calculations of the height profiles of nucleated sulfate aerosol particles for the northern mid-latitudes and tropics in winter are presented. Numerical calculations were performed using a three-dimensional model of the transport and transformation of multicompo- nent gas and aerosol substances in the atmosphere, incorporating photochemistry, nucleation involving neutral molecules and ions, as well as condensation/evaporation and coagulation. It is found that the resulting dynamics of the formation of aerosol particle nuclei is not a simple sum of ion and binary (water vapor/sulfuric acid) nucleation rates. This dynamics is determined by the ratio of critical radii of nucleated particles due to binary and ion nucleation of these substances (rcr_bin and rcr_ion) depending on temperature, relative humidity, and ionization rate. This should be taken into account in modeling the gas and aerosol composition of the atmosphere and comparing calculated and observed data.

scholarly journals Role of Criegee intermediates in the formation of sulfuric acid at a Mediterranean (Cape Corsica) site under influence of biogenic emissions

2021 ◽  
Vol 21 (17) ◽  
pp. 13333-13351
Author(s):  
Alexandre Kukui ◽  
Michel Chartier ◽  
Jinhe Wang ◽  
Hui Chen ◽  
Sébastien Dusanter ◽  
...  
Keyword(s):  
Steady State ◽  
Sulfuric Acid ◽  
Organic Compounds ◽  
Rate Coefficients ◽  
Oh Radicals ◽  
Additional Source ◽  
So2 Oxidation ◽  
Criegee Intermediates ◽  
Volatile Organic

Abstract. Reaction of stabilized Criegee intermediates (SCIs) with SO2 was proposed as an additional pathway of gaseous sulfuric acid (H2SO4) formation in the atmosphere, supplementary to the conventional mechanism of H2SO4 production by oxidation of SO2 in reaction with OH radicals. However, because of a large uncertainty in mechanism and rate coefficients for the atmospheric formation and loss reactions of different SCIs, the importance of this additional source is not well established. In this work, we present an estimation of the role of SCIs in H2SO4 formation at a western Mediterranean (Cape Corsica) remote site, where comprehensive field observations including gas-phase H2SO4, OH radicals, SO2, volatile organic compounds (VOCs) and aerosol size distribution measurements were performed in July–August 2013 as a part of the project ChArMEx (Chemistry-Aerosols Mediterranean Experiment). The measurement site was under strong influence of local emissions of biogenic volatile organic compounds, including monoterpenes and isoprene generating SCIs in reactions with ozone, and, hence, presenting an additional source of H2SO4 via SO2 oxidation by the SCIs. Assuming the validity of a steady state between H2SO4 production and its loss by condensation on existing aerosol particles with a unity accommodation coefficient, about 90 % of the H2SO4 formation during the day could be explained by the reaction of SO2 with OH. During the night the oxidation of SO2 by OH radicals was found to contribute only about 10 % to the H2SO4 formation. The accuracy of the derived values for the contribution of OH + SO2 reaction to the H2SO4 formation is limited mostly by a large, at present factor of 2, uncertainty in the OH + SO2 reaction rate coefficient. The contribution of the SO2 oxidation by SCIs to the H2SO4 formation was evaluated using available measurements of unsaturated VOCs and steady-state SCI concentrations estimated by adopting rate coefficients for SCI reactions based on structure–activity relationships (SARs). The estimated concentration of the sum of SCIs was in the range of (1–3) × 103 molec. cm−3. During the day the reaction of SCIs with SO2 was found to account for about 10 % and during the night for about 40 % of the H2SO4 production, closing the H2SO4 budget during the day but leaving unexplained about 50 % of the H2SO4 formation during the night. Despite large uncertainties in used kinetic parameters, these results indicate that the SO2 oxidation by SCIs may represent an important H2SO4 source in VOC-rich environments, especially during nighttime.

scholarly journals The Synergistic Role of Sulfuric Acid, Bases, and Oxidized Organics Governing New‐Particle Formation in Beijing

2021 ◽  
Vol 48 (7) ◽  
Author(s):  
Chao Yan ◽  
Rujing Yin ◽  
Yiqun Lu ◽  
Lubna Dada ◽  
Dongsen Yang ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Particle Formation ◽  
New Particle Formation

The potential role of malonic acid in the atmospheric sulfuric acid - Ammonia clusters formation

Chemosphere ◽  
2018 ◽  
Vol 203 ◽  
pp. 26-33 ◽  
Author(s):  
Haijie Zhang ◽  
Hao Li ◽  
Ling Liu ◽  
Yunhong Zhang ◽  
Xiuhui Zhang ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Malonic Acid ◽  
Potential Role ◽  
Ammonia Clusters
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