The Physical and Chemical Effect of Manganese Oxides on Automobile Catalytic Converters

1994 ◽  
Author(s):  
Allen A. Aradi ◽  
Joseph W. Roos ◽  
Ben F. Fort ◽  
Thomas E. Lee ◽  
Robert I. Davidson
Keyword(s):  
Manganese Oxides ◽  
Chemical Effect ◽  
Catalytic Converters ◽  
Physical And Chemical

The bioavailability of sediment-bound Cd, Co, and Ag to the mussel Mytilus edulis

1997 ◽  
Vol 54 (1) ◽  
pp. 147-156 ◽  
Author(s):  
C Gagnon ◽  
N S Fisher
Keyword(s):  
Mytilus Edulis ◽  
Manganese Oxides ◽  
Assimilation Efficiency ◽  
Chemical Properties ◽  
Fulvic Acids ◽  
Organic Coating ◽  
Natural Sediment ◽  
Coated Particles ◽  
Sediment Particles ◽  
Physical And Chemical

Marine sediments, long thought to be a final repository of toxic contaminants in marine ecosystems, may also serve as a source of toxic contaminants for marine food chains. The influence of physical and chemical properties of oxidized sediments on the bioavailability of metals from sediments to marine filter-feeding invertebrates is largely unknown. We examined the relative importance of specific sedimentary components that may affect the uptake of Cd, Co, and Ag by the mussel Mytilus edulis. Iron and manganese oxides, montmorillonite clay, silica, and natural sediment particles were radiolabeled with 109Cd,57Co, and 110mAg; some particles were also coated with marine fulvic acids to simulate the influence of organic coating on metal bioavailability. Mussels were fed radiolabeled particles and then allowed to depurate by feeding on nonradioactive particles, following a pulse-chase protocol developed to determine assimilation efficiencies of ingested metals. Metals were absorbed by mussels from all sediment particles, but metals associated with organic-coated particles were generally absorbed to a greater extent than metals associated with uncoated particles; absorption efficiencies were as high as 34% (for Co from organic-coated silica particles). Desorption experiments with radiolabeled particles at pH 5 were performed in parallel to simulate the behavior of food-bound metals in the acidic gut of bivalves. High correlations (r > 0.97) between the amount of metal desorbed under these conditions and the assimilation efficiency for metal bound to particles were noted among organic-coated particles but not uncoated particles (r < 0.6). Differences between coated and uncoated particles were principally due to differences in gut transit times of the ingested particles. These results suggest that suspended sediment particles may be a source of metals for suspension-feeding animals, but the relationship between metal partitioning to sediments and biological availability is not obvious, because organic coatings and the acidic gut environment influence metal absorption in mussels.

Physical and Chemical Methods of Methane Utilization in Ukrainian Coal Mines

2018 ◽  
Vol 277 ◽  
pp. 147-156 ◽  
Author(s):  
Ella Maksymova ◽  
Mykola Ovchynnikov ◽  
Roman Lysenko ◽  
Svitlana Kostrytska
Keyword(s):  
Oil And Gas ◽  
Coal Mines ◽  
Energy Resource ◽  
Hydrate Formation ◽  
Chemical Effect ◽  
Chemical Methods ◽  
Associated Gas ◽  
Physical And Chemical ◽  
Methane Utilization ◽  
Hydrate Formation Process

Associated gas of coal and minor oil deposits emitting into the atmosphere is considered to be valuable energy resource requiring proper utilization both from the economic and environmental viewpoints. It is proposed to develop mobile gas-hydrate plants to utilize associated gas of mines and minor oil and gas deposits. Hydrogenerating technology to collect and utilize coalmine methane immediately at the degassing wells of coal mines and oil extraction platform has been developed. Thermobaric parameters along with physical and chemical effect upon hydrate-formation process have been substantiated and selected. Certain degree of mechanical impact as well as magnetic field and ultrasound influence upon the process of hydrate formation has been proved. The technology will make it possible to obtain end product within the degassing area for its further transportation to consumers at long distances.

scholarly journals A comparative analysis of platinum and oxide-based catalytic converters in terms of NOx reduction with ammonia

2012 ◽  
Vol 150 (3) ◽  
pp. 55-62
Author(s):  
Wojciech KAMELA ◽  
Stanisław KRUCZYŃSKI
Keyword(s):  
Comparative Analysis ◽  
Diesel Engine ◽  
Catalytic Properties ◽  
Nox Reduction ◽  
Active Surface ◽  
Catalytic Converters ◽  
Nitric Oxides ◽  
Exhaust Gases ◽  
Conversion Rates ◽  
Physical And Chemical

The paper presents a comparison of the catalytic properties of two types of catalytic converters (containing platinum and oxide active coatings) in the aspect of a reduction of nitric oxides with ammonia. The tests were performed for three concentrations of ammonia in the exhaust gases of a diesel engine. The work contains images of the topography of the active surface of the catalytic converters and the results of its physical and chemical analysis. The changes of the conversion rates of the nitric oxides have also been presented in the converter temperature range from 150 to 550 °C along with the results of calculations of the shares of NO2 in NOx for all analyzed concentrations of ammonia in the exhaust gases.

scholarly journals Power Measurement by Calorimetric Method Using Water Infrequency Range Between 1.7 Mhz To 3 Mhz

2018 ◽  
Vol 7 (3.32) ◽  
pp. 106 ◽  
Author(s):  
F Shokrollahi ◽  
K K. Lau ◽  
W H. Tay ◽  
L S. Lai
Keyword(s):  
Electrical Power ◽  
Power Measurement ◽  
Chemical Effect ◽  
Calorimetric Method ◽  
Liquid Volume ◽  
Co2 Absorption ◽  
Ultrasonic Power ◽  
Absorption Process ◽  
Ultrasound Technique ◽  
Physical And Chemical

Absorption is one of the most established processes for CO2 capturing. However, the current technologies used in this process suffer from several drawbacks. Meanwhile, the ultrasound technique is proposed as a new alternative technology to assist the CO2 absorption process due to both its physical and chemical effects. Yet, the chemical effect is still under developments. Between all the influencing parameters, the ultrasonic power and the frequency are the vital key parameters to investigate sonochemical effects during the CO2    absorption process. The aim of this paper is to measure the ultrasonic power of an ultrasonic vessel. The total electrical power measured by using the voltage and the flow. Simultaneously, the ultrasonic power determined by using the calorimetric method. The measurements were done by using water with different volumes and repeated for three different frequencies. The results showed that almost 51% of the electrical power converted into the ultrasonic power and were independent of liquid volume.  

scholarly journals Mining Activities and the Chemical Composition of R. Modonkul, Transbaikalia

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 979
Author(s):  
Zinaida Ivanovna Khazheeva ◽  
Aleksey Maksimovich Plyusnin ◽  
Olga Konstantinovna Smirnova ◽  
Elena Georgievna Peryazeva ◽  
Dashima Ivanovna Zhambalova ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Chemical Composition ◽  
Manganese Oxides ◽  
High Concentration ◽  
Catchment Basin ◽  
Industry Waste ◽  
Major Cations ◽  
Calcium Magnesium ◽  
Physical And Chemical ◽  
The Impact

The Dzhidinsky orefield is located in the Zakamensky district of Buryatia. It is characterized by a high concentration of mineralization in a small area. The ores of the Dzhidinsky economic deposits are complex. This ore field includes Pervomaiskoye Mo, Kholtosonskoe W, and Inkurskoe W deposits. The catchment basin of the river Modonkul is located in the Dzhidinsky orefield. Mineral resource industry waste is a real threat to the city Zakamensk. Currently, the waste of deposits is located at the floodplain terrace and the watershed of the river Modonkul. In this work, the impact of the drainage mine and tributary Inkur on the formation chemical composition of the river Modonkul is studied. The 80 samples of water and suspended matter were taken from a surface of 0–0.5 m on seven sites. Physical and chemical parameters were measured at the sampling sites, and chemical composition was analyzed in the laboratory. In the natural background of the river, the major cations are, in decreasing order, Ca2+ > Mg2+ > Na+ + K+, and major anions are, also in decreasing order, HCO3− > SO42− > Cl−. Along the river, the chemical type of water changes from bicarbonate to sulfate across the sulfate-bicarbonate or bicarbonate-sulfate class and from calcium-magnesium across sodium-calcium-magnesium reverse calcium-magnesium group. Total dissolved solids (TDS) increase by a factor of 4.0–4.7 between the upper and mouth of the river. The dissolved and suspended loads were studied in the mixing zone of acid mine and river water. The different hydrochemistry characteristics may result from Fe, Al, and Mn hydroxide precipitation. The pH values and dissolved oxygen cycles could change the uptake of heavy metals on suspended iron and manganese oxides, and the mechanism of removing it in water. River particulates have the potential of regulating heavy metal inputs to aquatic systems from pollution. The ore elements or the heavy metals are removed from the water in two ways: by the runoff of Modonkul and the sedimentation of suspended material at the bottom. The inflow of mine water into the Modonkul river leads to the rare earth elements (REEs) composition with negative cerium and positive europium anomalies.

scholarly journals Weathering Processes and Mechanisms Caused by Capillary Waters and Pigeon Droppings on Porous Limestones

Minerals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 18
Author(s):  
David Benavente ◽  
Marli de Jongh ◽  
Juan Carlos Cañaveras
Keyword(s):  
Chemical Effect ◽  
Salt Weathering ◽  
Capillary Water ◽  
Material Loss ◽  
Weathering Processes ◽  
Geochemical Study ◽  
Pigeon Droppings ◽  
Deterioration Process ◽  
Dehydration Processes ◽  
Physical And Chemical

This investigation studies the physical and chemical effect of salt weathering on biocalcarenites and biocalcrudites in the Basilica of Our Lady of Succour (Aspe, Spain). Weathering patterns are the result of salty rising capillary water and water lixiviated from pigeon droppings. Surface modifications and features induced by material loss are observable in the monument. Formation of gypsum, hexahydrite, halite, aphthitalite and arcanite is associated with rising capillary water, and niter, hydroxyapatite, brushite, struvite, weddellite, oxammite and halite with pigeon droppings. Humberstonite is related to the interaction of both types of waters. Analysis of crystal shapes reveals different saturation degree conditions. Single salts show non-equilibrium shapes, implying higher crystallisation pressures. Single salts have undergone dissolution and/or dehydration processes enhancing the deterioration process, particularly in the presence of magnesium sulphate. Double salts (humberstonite) have crystals corresponding to near-equilibrium form, implying lower crystallisation pressures. This geochemical study suggests salts precipitate via incongruent reactions rather than congruent precipitation, where hexahydrite is the precursor and limiting reactant of humberstonite. Chemical dissolution of limestone is driven mainly by the presence of acidic water lixiviated from pigeon droppings and is a critical weathering process affecting the most valuable architectural elements present in the façades.

scholarly journals Physical and chemical bases of decarburization of high-carbon ferromanganese melt

2020 ◽  
Vol 1,2020 (1,2020 (124)) ◽  
pp. 30-35
Author(s):  
Velychko O ◽  
Yunshen Du ◽  
Mianovska Ya ◽  
Kamkina L ◽  
Ankuninov R
Keyword(s):  
Manganese Oxides ◽  
Low Carbon ◽  
High Carbon ◽  
Mixing Processes ◽  
Metallic Manganese ◽  
Low Phosphorus ◽  
High Carbon Ferromanganese ◽  
Patterns Of Behavior ◽  
Manganese Ferroalloys ◽  
Physical And Chemical

The aim of the work is to establish physicochemical patterns of behavior of carbon, silicon, manganese when using the method of oxygen purge of high-carbon ferromanganese. Method. The process of blowing red metal to sour is neglected. With the fusion of fused acid, it is more important to oxidize silicon. Its presence in metal is practical in the block of oxidized manganese. Because oxygen is an assimilation gas, the mixing processes of the converter bath components and the reduction of manganese oxides at the metal-slag interface do not develop properly during purging. The smelters of the medium-carbonaceous ferromanganese in the converter are characterized by a stable chemical warehouse and even a higher number of vimogs for this type of alloy. The low concentration of silicon in metal over a number of swimming trunks can be easily shoved with a hat of pre-purge bathtub with sour at the final stage of refining. The behavior of phosphorus in these smelts is not controlled. The content of P2O5 in the final slag is 0.1%. To achieve acceptable concentrations of phosphorus in the metal, it is necessary to use starting materials with a low phosphorus content. Scientific novelty.Taking into consideration the high affinity of silicon for oxygen, the physical and chemical basis for the production of medium-carbon ferromanganese, as well as metallic manganese and low-carbon ferromanganese, is the process of the interaction of manganese oxides of a certain basicity slag melt with silicon dissolved in ferromanganese (manganese), that is, as combined reduction -refining process to produce manganese ferroalloys with a given silicon content standard

scholarly journals Preparation of nano manganese oxides by H2O2 in-situ oxidation: effect of regulation mechanism on physical and chemical properties

2021 ◽  
Author(s):  
Mingdong Li ◽  
Jiawei Wang ◽  
Dejin Fu ◽  
Bibo Gou ◽  
Xiaoliang Chen ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Manganese Oxides ◽  
Ph Value ◽  
Chemical Properties ◽  
Manganese Sulfate ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract Manganese oxides showed many special physicochemical properties in many fields such as electrochemistry, adsorption and catalysis. They were widely used in cathode materials for lithium batteries, molecular sieves, catalytic materials and adsorbents. In this paper, in situ oxidation of manganese sulfate solution was conducted with H2O2 as oxidant, and the characterization means of XRD, SEM and BET were used. The purpose was to study the effects of different regulation mechanisms on the physical and chemical properties of manganese oxides such as morphology, phase composition, surface properties and specific surface area. The adsorption properties of γ-MnO2 for Co and Ni in manganese ore leaching solution were tested. The results showed as follows. Under alkaline conditions, the main product of manganese sulfate solution oxidized by H2O2 was Mn3O4 spherical particles with a radius of about 50 nm, these particles had micropores or mesopores, the oxidation reaction rate was rapid, and the specific surface area and N2 adsorption capacity changed with the change of reaction conditions.The temperature had a great influence on the micro morphology of the product.The micro morphology was slender nanorod when the temperature was 20℃. With the increase of temperature, the length of nanorod became shorter. When the temperature rises to 50℃, the rod became spherical. When the pH value decreased from 9 to 7, the diffraction peak of each crystal plane in the product Mn3O4 decreased gradually. The diffraction peak of γ-MnO2 appeared when the pH value decreased to 5. All the products were γ-MnO2 when the pH value decreased to 3. With the increase of Mn2+ concentration, the grain size decreased and agglomeration was easy to occur. The optimum conditions were obtained as follows: the temperature was 30℃, pH was 3, reaction time was 90 min, the mole ration of H2O2 to Mn2+ was 1:1, and Mn2+ concentration was 10g/L. Under the optimum conditions, γ-MnO2 with high specific surface area (172.41 m2/g) was prepared. This γ-MnO2 has a good adsorption effect on Co and Ni in manganese ore leaching solution, and the adsorption efficiency could be reached 94.75 % and 95.67 %. This study would provide a reference for the preparation of manganese oxides with different physical and chemical properties.

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

Biophysical Measurement of Molecular Weight of Foot-and-Mouth Disease RNA Fragments

1974 ◽  
Vol 32 ◽  
pp. 262-263
Author(s):  
Sydney S. Breese ◽  
Howard L. Bachrach
Keyword(s):  
Chemical Properties ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Distilled Water ◽  
Bovine Plasma ◽  
Mouth Disease Virus ◽  
Foot And Mouth ◽  
Carbon Coated ◽  
Rna Fragments ◽  
Physical And Chemical

Continuing studies on the physical and chemical properties of foot-and-mouth disease virus (FMDV) have included electron microscopy of RNA strands released when highly purified virus (1) was dialyzed against demlneralized distilled water. The RNA strands were dried on formvar-carbon coated electron microscope screens pretreated with 0.1% bovine plasma albumin in distilled water. At this low salt concentration the RNA strands were extended and were stained with 1% phosphotungstic acid. Random dispersions of strands were recorded on electron micrographs, enlarged to 30,000 or 40,000 X and the lengths measured with a map-measuring wheel. Figure 1 is a typical micrograph and Fig. 2 shows the distributions of strand lengths for the three major types of FMDV (A119 of 6/9/72; C3-Rezende of 1/5/73; and O1-Brugge of 8/24/73.

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