• Mon - Sun: 24/7 online service for you
Get A QUOTE

morphological investigation of calcium carbonate during

In situ formation of surface-functionalized ionic calcium carbonate ...

This paper reports a new route to synthesize calcium carbonate (CaCO3) ... X-ray powder diffraction investigation confirmed that the CaCO 3 inner core had a calcite crystalline structure, ... 2014 Morphology controlling of calcium carbonate by self-assembled surfactant micelles on PET substrate. RSC Adv. 4, ...

WhatsApp:+8617329420102

The effect of carboxymethyl chitosan on the precipitation of calcium ...

(CMCS), and further used as an additive in the crystallization process of calcium carbonate (CaCO 3). The combination investigation of XRD, Micro FT-IR and SEM on the precipitated crystals shows that the addition of CMCS obviously changed the crystal morphology, but did not induce the transformation of the crystal form, i.e., CaCO 3 keeps calcite

WhatsApp:+8617329420102

Spinning up the polymorphs of calcium carbonate - PMC

Controlling the growth of the polymorphs of calcium carbonate is important in understanding the changing environmental conditions in the oceans. Aragonite is the main polymorph in the inner shells of marine organisms, and can be readily converted to calcite, which is the most stable polymorph of calcium carbonate.

WhatsApp:+8617329420102

Crystallization and Aggregation Behaviors of Calcium Carbonate in the ...

When the SDS concentrations were lower than the onset of interaction between PVP and SDS, the precipitated CaCO 3 crystals were typically hexahedron-shaped calcite; the increasing SDS concentration caused the morphologies of CaCO 3 aggregates to change from the flower-shaped calcite to hollow spherical calcite, then to solid spherical vaterite.

WhatsApp:+8617329420102

Investigation of calcium carbonate precipitation in the presence of ...

The aim of this work is to study the effect of a water-soluble biopolymer, carboxymethyl inulin (CMI), on the crystallization of calcium carbonate. We have investigated the effect of the feed rate of the reactant and the concentration of the biopolymer on the surface area, particle size and size distribution, final morphology and polymorph of calcium carbonate crystals during a precipitation ...

WhatsApp:+8617329420102

CiteSeerX — CALCIUM CARBONATE GROWTH MODIFICATION BY CONSTITUENTS ...

CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): Filtration of a suspension of calcium carbonate (CaCO 3) or other inorganic solutions are often part of the methodology for recovering crystals during biomimetic mineralization experiments performed by various procedures. However, the use of cellulose filter membranes (FM) may cause a problem in in vitro ...

WhatsApp:+8617329420102

Characterization of Geobacillus stearothermophilus and its application ...

3 days agoA study of size and morphology of calcium carbonate crystals was made using SEM. Figure 15 shows the SEM image of CaCO 3 crystals produced by G. stearothermophilus. The calcium carbonate crystals exhibit uneven and spherical shape with average particle size of 32 ± 0.95. This result confirmed the crystal as mainly composed of calcite.

WhatsApp:+8617329420102

Precipitated Calcium Carbonate - Multifunctional Additive for PVC

The manufacture of synthetic calcium carbonate by the reaction of gaseous carbon dioxide with a colloidal suspension of calcium hydroxide is sufficiently versatile to produce different morphologies. Distinctive and reliable reaction control criteria exist for the manufacture of PCC where morphology and crystalline size can be varied at will.

WhatsApp:+8617329420102

Mineralogy of microbially induced calcium carbonate precipitates formed ...

Oct 16, 2020Using Raman microspectroscopy, amorphous calcium carbonate (ACC) was observed first in the drops, followed by vaterite formation. ACC and vaterite remained stable for up to 4 days, possibly due to...

WhatsApp:+8617329420102

British Library EThOS: Experimental investigation of calcium carbonate ...

This was done by determining the influence of solution chemistry (SO4 and Mg) on calcium carbonate formation, mineralogy and stability via a variety of laboratory and synchrotron based synthesis experiments. During the formation of aragonite and calcite, aqueous SO4 and the Mg/Ca ratio both affect the formation of calcite and aragonite.

WhatsApp:+8617329420102

Synthesis of Calcium Carbonate by Semicontinuous Carbonation ... - Srce

process of precipitation of calcium carbonate, its crystal size and morphology were systematically investigated. The synthesis was performed under adjustable super-saturation by using a semicontinuous process. EXPERIMENTAL . The precipitation of calcium carbonate was performed in a thermostated glass reactor of 1.6 dm 3 total volume capacity.

WhatsApp:+8617329420102

Textural properties of synthetic nano-calcite produced by hydrothermal ...

3 1 1. Introduction 2 Calcium carbonate is an inorganic compound that has been widely studied due to its 3 abundance in nature as a mineral and biomineral. Calcium carbonate particles have three 4 crystal morphologies and structures, which are generally classified as rhombic calcite, needle- 5 like aragonite and spherical vaterite. Calcite belonging to Trigonal-Hexagonal-Scalenohedral

WhatsApp:+8617329420102

The effect of surface wettability on calcium carbonate precipitation in ...

2 days agoTotal calcium concentration and pH values were measured at the outlet of the beds during calcium carbonate precipitation in homogeneously hydrophobic and hydrophilic beds at SR i = 537, 222 and 86, and decreased with time (Fig. 2 and Fig. S1). The calcium concentration and pH reduction were an indication of calcium carbonate precipitation in ...

WhatsApp:+8617329420102

US20050276897A1 - Ultra-dry calcium carbonate - Google Patents

Ultra-dry calcium carbonate particles, a method for drying calcium carbonate particles and also the use of the resulting dried calcium carbonate as a flow property regulating agent in sealing compounds or adhesive compositions. The calcium carbonate particles are dried with microwaves. The drying can take place in a continuous belt apparatus, a batch treatment apparatus or a rotary-tube ...

WhatsApp:+8617329420102

Crystallization of calcium carbonate in a large-scale push-pull heat ...

Wang et al. ( 2013) supported this for calcium carbonate polymorphs experimentally. According to their study, calcite crystallization is favored at high concentration gradients, whereas high temperatures favor aragonite crystallization. Already Wray and Daniels ( 1956) reported that aragonite is prevailing over calcite at 45,^ {circ }hbox {C}.

WhatsApp:+8617329420102

An Investigation of The Mechanisms of Calcium Isotopic Fractionation in ...

A pH, ATC and calcium ISE probes monitor the solution during crystal formation. The reactor is submersed in a water bath to control the temperature of the solution and is mixed by use of a submersible stir plate and Teflon stir bar. Pg. 18 Figure 4. Color change of HNB indicator during EDTA titration before (left) and after (right) the

WhatsApp:+8617329420102

Investigation of Electrolyte-Dependent Carbonate Formation on Gas ...

a hydroxide to form a carbonate (CO 3 2−) and water CO OH HCO (aq) 23 + F −− (1) HCO (aq) OH CO (aq) H 33F O 2 ++ 2 −−− (2) Carbonate formation presents an issue in a variety of applications, for example, the formation of calcium carbonate scale in water purification systems.18 The natural uptake of CO 2 by the oceans, which acts ...

WhatsApp:+8617329420102

Insights into the influence of cell concentration in design and ... - PLOS

Jul 12, 2021The rate and kinetics of calcium carbonate precipitation, in turn, affect not only the quantity of calcium carbonates but also the morphology and quality of precipitated crystals. In nature, calcium carbonate exists in six polymorphs including calcite, aragonite, vaterite, CaCO 3 monohydrate, CaCO 3 hexahydrate to amorphous CaCO 3 [15, 21].

WhatsApp:+8617329420102

Eggshells as natural calcium carbonate source in combination with ...

ents. With 37.3% of the total weight, calcium is the main mineral component (the mostly in crystalline form exist-ing calcium is calcium carbonate (CaCO 3) with 93.6% followed by calcium triphosphate (0.8%) and magnesium carbonate). According to the different structures of the egg, the protein content in the eggshell could vary. The organic

WhatsApp:+8617329420102

Advances in the identification of calcium carbonate urinary crystals

crystal morphology, and birefringence features under polarized light [6]. When this approach ... L-thyroxine, and rosuvastatine respectively. Laboratory investigation was normal but for a reduced e-GFR-MDRD (51 ml/min/1.73 m2, normal value: ... calcium carbonate into calcite in the sea urchin larval spicule, Proc. Natl. Acad. Sci. USA 105 (2008 ...

WhatsApp:+8617329420102

Preparation and characterization of calcium carbonate microspheres and ...

The influence of lecithin from egg yolk (LE) on calcium carbonate (CaCO3) biomineralization was investigated. In the present study, spherical CaCO3 particles were synthesized via coprecipitation in the presence of LE. LE multilamellar liposomes were first tuned by sonication to provide better control over the nucleation of CaCO3. Subsequently, monodisperse microspheres ~2 µm in size were ...

WhatsApp:+8617329420102

A mild route for the preparation of calcium carbonate rod bundles in ...

Jan 20, 2021The morphology of the CaCO 3 sample was observed by field emission scanning electron microscope (FESEM, SU8020 electron microscope, from , the samples were ultrasonically dispersed for 10 min with ethanol, dropped on the cleaned silicon wafer, then tested with accelerating voltage 15 kV after the surface was sprayed with gold).

WhatsApp:+8617329420102

Morphology of calcium carbonate precipitate with different additives ...

however, carbonation curing is mostly investigated on lab-scale, due to two main challenges that should be addressed before it can be widely applied for industrial-scale production: (1) co2...

WhatsApp:+8617329420102

Morphological characteristics of calcium carbonate crystallization in ...

May 5, 2022The morphological characteristics of CaCO 3 were statistically analyzed in terms of long-axis length ( b ), short-axis length ( a ), and aspect ratio ( K = b / a ). As CO 2 pressure increases, b is almost unchanged from 0.8-1.8 μm, a decreases from 0.7 to 0.4 μm, and, consequently, K increases from 1.3 to 2.5.

WhatsApp:+8617329420102

Inactivation of human norovirus and its surrogate by the disinfectant ...

The disinfectant with calcium hydrogen carbonate mesoscopic crystals inactivated noroviruses along with the destruction of viral capsids. ... Morphological change of MNV was observed by TEM without or after 100 s of CAC ... further investigation is required for evaluating its safety when applying to humans and animals. The duration of efficacy ...

WhatsApp:+8617329420102

Formation and Stabilization of Vaterite Calcium Carbonate by Using ...

This paper aimed to study the effects of natural polysaccharide (gum arabic, GA) on the formation of vaterite calcium carbonate and its stability in aqueous solution. Gum arabic is a macromolecule that has a high molecular weight and is amphoteric in character. A 0, 2.5, 5 or 10 ml of GA solution (30%) was added to the calcium chloride solution with various initial concentrations to prepare ...

WhatsApp:+8617329420102

pH-Dependent Schemes of Calcium Carbonate Formation in the Presence of ...

formation and morphology.37−40 Lately, the role of prenuclea-tion clusters in mineralization is emerging to be significant in different mineral systems including calcium phosphates, calcium carbonates, and iron(oxy) (hydr)oxides.15,16,18,23,41,42 The structure and stability of such mineral precursor species as

WhatsApp:+8617329420102

Investigation of calcium carbonate synthesized by steamed ammonia ...

The aim of this work is to study the effect of reaction conditions using steamed ammonia liquid waste without the use of additives on the crystallization of calcium carbonate. CaCO 3 was prepared by steamed ammonia liquid waste (CaCl 2 ) and (NH 4 ) 2 CO 3 .

WhatsApp:+8617329420102

Investigation of calcium carbonate synthesized by steamed ammonia ...

The morphology of the calcium carbonate particles obtained in the 200 and 600 rpm min −1 are presented in Fig. 6. We can concluded that the different stirring speed in the system ( Fig. 6a-d) was an effective method to control the morphology of the CaCO 3.

WhatsApp:+8617329420102

Polymorph Selection of Calcium Carbonate by The Morphology of ...

During this period, the E-commerce and registration of new users may not be available for up to 6 hours. ... POLYMORPH SELECTION OF CALCIUM CARBONATE BY THE MORPHOLOGY OF BIOMACROMOLECULES: FROM ARAGONITE, VATERITE TO CALCITE. JUNWU XIAO, ... Investigation at the micrometer scale of pancreatic calcifications in chronic pancreatitis by μFTIR ...

WhatsApp:+8617329420102

On the growth of calcium carbonate in the presence of Cr(VI)

The extended use of hexavalent chromium Cr(VI) compounds in industrialprocesses caused a significant increase of the concentration of thishighly toxic heavy metal in natural environments. In order toinvestigate the influence of Cr(VI) in the formation of CaCO3,crystallization experiments were carried out in a double diffusionsystem, using silica hydrogel with different Cr(VI) contents as ...

WhatsApp:+8617329420102

Agronomy | Free Full-Text | Humic Acids Formation during Compositing of ...

4 days agoFeature Papers represent the most advanced research with significant potential for high impact in the field. Feature Papers are submitted upon individual invitation or recommendation by the scientific editors and undergo peer review prior to publication.

WhatsApp:+8617329420102

Nonclassical crystallization of zinc carbonate hydroxide hydrate ...

4 days agoThis study demonstrates that the formation of the ZCHH is transformed from an even more unstable amorphous phase, AZC. The liquid-like morphology of AZC is similar to amorphous carbonate phases, such as amorphous calcium carbonate (ACC), suggesting that AZC also precipitates via a liquid-liquid phase separation mechanism.

WhatsApp:+8617329420102

Investigation on mineralization performance and spore germination ...

Jun 17, 2022Microbial induced calcium carbonate precipitation (MICP) provides a theoretical basis for repairing underground rocks. The optimal germination conditions and mineralization activities of Bacillus pasteurii with crack repair function were investigated. The growth and mineralization properties of microorganisms in different environments were explored by measuring the urease activity and calcium ...

WhatsApp:+8617329420102

Rheo-SANS investigation of acicular-precipitated calcium carbonate ...

The rheology and particle alignment of suspensions of anisotropic-precipitated calcium carbonate particles of various aspect ratios is investigated using small-angle neutron scattering simultaneous with rheological measurement (Rheo-SANS).

WhatsApp:+8617329420102

Bacterially Induced Mineralization of Calcium Carbonate: The Role of ...

Introduction. Bacterially induced and mediated mineralization is a research subject widely studied in the past decades (Banfield & Hamers, 1997; Douglas & Beveridge, 1998; Ehrlich, 2002).Due to its numerous consequences, bacterially induced precipitation of calcium carbonate, so-called carbonatogenesis (Rodriguez-Navarro et al., 2003), has attracted much attention from both basic and applied ...

WhatsApp:+8617329420102

Influence of Sodium Dodecyl Benzene Sulfonate on Crystallization ...

The effect of SDBS of different concentrations on the crystallization behavior and morphology of CaCO 3 in solution was studies. The results of scanning electron microscopy(SEM), X-ray diffraction(XRD) and Fourier transform infrared spectroscopy ... Influence of Sodium Dodecyl Benzene Sulfonate on Crystallization Behavior of Calcium Carbonate ...

WhatsApp:+8617329420102

Frontiers | Calcium Carbonate Precipitation for CO2 Storage and ...

The transformation of CO2 into a precipitated mineral carbonate through an ex situ mineral carbonation route is considered a promising option for carbon capture and storage (CCS) since (i) the captured CO2 can be stored permanently and (ii) industrial wastes (i.e., coal fly ash, steel and stainless-steel slags, and cement and lime kiln dusts) can be recycled and converted into value-added ...

WhatsApp:+8617329420102

Crystal growth and morphology of calcium oxalates and carbonates

The main purpose of the research described in this thesis is to establish a relationship between the crystal structure and morphology of calcium oxalate and calcium carbonate crystals grown from aqueous solutions.

WhatsApp:+8617329420102

Solubility and bioavailability of stabilized amorphous calcium carbonate

after verifying the polymorph composition of the calcium carbonate preparations, we studied the dissolution rate and solubility of the synthetic acc prepared for this assay compared with the crystalline forms of calcium carbonate. ph measurements represent the number of unbound h + ions, which directly correlates with the number of dissolved co .

WhatsApp:+8617329420102

Related Posts

Solve the problem?
Get the latest quotation? Hit The Button.

Online Service