The application of the shrinking core model to the generated data shows that the reaction between dolomite and sulphuric acid is film diffusion control with a first-order reaction (0.6587) and ...
Dolomite is a mineral and a rock-forming mineral that is composed of calcium magnesium carbonate (CaMg(CO3)2). It is named after the French mineralogist Déodat Gratet de Dolomieu, who first …
The thermodynamic analysis of the thermal decomposition reaction of carbonates showed that the temperatures of thermal stability of dolomite and magnesium carbonate are very similar. Kinetics of isothermal and non-isothermal decompositions of natural dolomite in air atmosphere were investigated. Under the examined conditions, …
For example, in a study of (Ca, Mg)CO 3 film growth on dolomite, higher friction was generally observed on Ca-rich films (Ca/Mg ratio > 1) [44] in comparison with dolomite, whereas in Mg-rich ...
compare with the actual concentration of seawater? Is seawater saturated with respect to gypsum? Concentrations and activity coefficients for seawater are: Ca2+ = 10.28 x 10-3 =0.28; SO 4 2-= 28.00 x 10-3 =0.12 If the sulfate concentration is 25.0 x 10-3 mol kg-1 and the seawater is at solubility equilibrium then the concentration of Ca2+ is ...
Although the peak location of starch does not change obviously in the XRD pattern, the intensities increased significantly due the addition of dolomite into the TPS film (refer to the diffraction peaks 2θ at around 22° for TPS film and TPS-5wt%DOL(P)) film. The degree of crystallinity of the TPS film was increased from 25.38% to 51.79% when ...
This article elucidates the effect of type of pigment/extenders viz. titanium dioxide (TiO2), magnesium silicate (steatite), calcium carbonate, dolomite, precipitated sodium magnesium aluminosilicates, hydrated and calcined aluminum silicates (kaolin) when used alone or in combination in the paint dispersions on their sedimentation …
The crystal structure of dolomite is similar to calcite with Mg ions substituting for Ca in every other layer. To accommodate this substitution, due to differences in bond lengths between Ca–CO 3 and Mg–CO 3 (238 pm versus 208 pm, respectively), CO 3 in the Mg layer is uniformly rotated about the threefold axis relative to calcite (Reeder and …
The impedance value increases with further increasing H 3 PO 4 concentration or increasing the immersion time reflecting the passivation of the oxide film on the Ti-6Al-4V alloy surface forming ...
optimized parameters referred to the temperature, the acid concentration, the time and particle size. It was found that the leaching temperature was 80°C, the acid concentration was 2 mol/L, the leaching time - 60 minutes, while the particle size - 0.01 mm. The dolomite ore leaching efficiency reached 99.3 % under these conditions.
The "dolomite problem", which has confused scientists for nearly two centuries, is an important fundamental geological problem. The mineralogical characteristics of carbonate minerals show that the …
To clarify the effects of sulfate concentration and salinity in the mineralization of dolomite, we conducted experiments on dolomite precipitation mediated by a halophilic archaeon, Natrinema sp. J7-1 with various sulfate concentrations and salinities. This strain was cultured in a series of modified growth media (MGM) with …
transparent film, then the spectra was scanned and analyzed. The spectra of samples were recorded at 25°C in the range of 4000-500 cm−1. ... The effect of NaOL concentration on apatite and dolomite is given in Fig. 4. It can be seen that the recovery of apatite and dolomite increased with NaOL concentration up to 3.0×10-4 mol/dm3. When
The deposition of a calcium oxalate layer on dolomite demonstrates potential application in stone culture heritage conservation. However, due to insufficient coverage and the presence of cracks, the film's usefulness is restricted. In this investigation, we used a simple two-step procedure to create a cohesive and uncracked …
Dolomite, type of limestone, the carbonate fraction of which is dominated by the mineral dolomite, calcium magnesium carbonate. Along with calcite and aragonite, dolomite makes up approximately 2 percent of the …
Dolomite, a calcium magnesium mineral (CaMg(CO3)2), is considered an undesirable accompanying mineral in the phosphoric acid production process and, as such, large quantities of this mineral are available in Florida. This study is aimed toward the characterization of the high-concentration phosphatic dolomite pebbles (handpicked …
The aim is to explore new depressants for achieving the efficient separation of apatite and dolomite. In this work, fucoidan (FD) was examined as an eco-friendly dolomite depressant to separate dolomite from apatite. The depression ability and adsorption mechanisms were investigated. The flotation results indicated that FD …
Dolomite, CaMg(CO 3) 2, is an abundant carbonate mineral in ancient rock formations, but it is extremely scarce in modern sedimentary environments. This intriguing observation has been repeatedly referred …
Dolomite CaMg(CO 3) 2 is a thermodynamically stable carbonate mineral that composes about 30% of the sedimentary carbonate mineralogy in Earth's crust (1–3).Despite its geochemical abundance, nearly two centuries of sustained scientific efforts have failed to precipitate dolomite in the laboratory near ambient conditions ().One remarkable long …
Volumetric dolomitization, by means of pressure-solution-mediated volumetric replacement of calcite by dolomite, causes the Ca 2+ concentration (Eq. 2) and rate of …
PDF | Steady-state dissolution rates of dolomite were measured at 25°C in a mixed-flow reactor as a function of pH (from 5-12), ionic strength (0.002 <... | Find, read and cite all the research ...
The external mass transport of sorbate and external film diffusion in this sorption system was very fast in comparison with the intraparticle diffusion and adsorption. ... Comparison of different adsorption reaction models for Bakken oil adsorption onto hydrophobic dolomite at three different concentration (a) 3000 ppm, (b) 5000 ppm, …
Naturally high uranium (U) concentrations occur in the groundwater of northern Bavaria (southeastern Germany) although the source(s) and geochemical processes controlling its occurrence are poorly understood. An earlier study identified the weathering of uraniferous apatite as responsible for elevated groundwater U in a part of …
The size of the film was 35×35 cm, the distance of the subjects from the X-ray tube was about six feet and the electrical voltage was 100 KV. Data analysis . ... Airborne concentration of dolomite dust was far beyond its current TLV of 10 mg/m3 . Therefore, it would be reasonable to attribute the prevalence of respiratory symptoms in …
Dolemite Is My Name est un film de Craig Brewer. Synopsis : Quand Hollywood l'a écarté dans les années 1970, le talentueux Rudy Ray Moore décide de produire ses propres... Dolemite Is My Name est un film de Craig Brewer. Synopsis : Quand Hollywood l'a écarté dans les années 1970, le talentueux Rudy Ray Moore décide de produire ses ...
Potassium has a different effect on the dolomite than Na at similar concentrations. Unlike Na, K does not cause micro‐strain but leads to dolomite with smaller unit cell parameters. It is ...
To decode the enigma of ancient dolomite, we examined a modern dolomite forming environment, and found that a cyclic shift in microbial community between …
2) Dolomite as a pH regulator Before a pond, be sure to check its total alkalinity with a water testing kit. Science History Institute, CC BY-SA 3.0, via Wikimedia Commons. Pond water acidity is influenced by a complex combination of factors, such as photosynthesis, carbon dioxide availability, water hardness, and pond …
Dolemite: Directed by D'Urville Martin. With Rudy Ray Moore, D'Urville Martin, Jerry Jones, Lady Reed. After he is released from jail, a pimp takes on the criminals and corrupt police officers who framed him in the first place.
The movie becomes the story of how Rudy, in 1974, takes his Dolemite character from the stand-up comedy stage to the big screen, all by putting together a so-slaspdash-it's-nutty independent ...
The presence of MgO, in dolomite, can cause several problems during production of phosphoric acid and final fertilizers. ... It was found that the acid concentration, PVA concentration, and ...
The deposition of a calcium oxalate layer on dolomite demonstrates potential application in stone culture heritage conservation. However, due to insufficient …
It is revealed that a variation of sulfate concentration in solution does not affect the formation of dolomite mediated by halophilic archaea, but an increase of salinity enhances this process, and under natural conditions, an increase in salinity may be more significant than the decrease of sulfates in microbe-mediated dolmite formation. In the …
The Boyd model provides information as to whether the rate controlling step results from film diffusion (boundary layer), or particle diffusion (diffusion inside the pores) [32]. ... is attributable to the splitting effect of the concentration gradient between sorbate and sorbent with increased dolomite concentration causing a decrease in ...
Reactive-transport models are developed here that produce dolomite via two scenarios: primary dolomite (no CaCO3 dissolution involved) versus secondary …
in nature, dolomite is not available in this exact proportion. Hence, in commercial parlance, the rock containing 40-45% MgCO 3 is usually called dolomite. Dolomite rock that contains either calcite or a mixture of calcite & magnesite in addition to dolomite is called "Dolomitic Limestone". It is grouped under flux & construction minerals and
Amorphous calcium carbonate (ACC) is a common precursor to crystalline calcium carbonate, and is of particular importance in biomineralization, where its crystallization in privileged environments ensures a pseudomorphic transformation. While organisms regulate this process using organic molecules and magnesium ions to …
A) Bright‐field TEM image and B) corresponding SAED pattern of a single crystal domain in dolomite film generated from ACC films prepared at [Ca²⁺] = 10 × 10⁻³ m and [Mg²⁺] = 100 × 10 ...
Dolomite (CaMg[CO 3] 2) is a common rock-forming mineral. Nevertheless, its mechanisms of formation and the factors that cause dolomite concentration variations within the sedimentary records …
The formation of early dolomite (primary and early diagenetic dolomite) in different lacustrine depositional systems coincidentally resulted from a significant …
