Effect of Calcium Carbonate on the Mechanical Properties and Microstructure of Red Clay

The influence of precipitated calcium carbonate on the strength and microstructure of red clay was studied. Precipitated calcium carbonate was added to red clay at ratios of 0%, 5%, 10%, 15%, and 20%. Shear tests were carried out on the samples to observe the effect of calcium carbonate on the mechanical properties of red clay. The results showed that, with increasing calcium carbonate content, the strength of red clay first decreased and then increased. The maximum strength was obtained for the sample with 20% calcium carbonate. Scanning electron microscopy (SEM) was used to observe the changes in microstructure caused by addition of calcium carbonate. The pores and cracks analysis system (PCAS) was used to quantitatively characterize the microstructure changes detected in SEM images. The addition of calcium carbonate decreased the pore area and increased the total number of pores of red clay. The incorporation of calcium carbonate caused the red clay particles to agglomerate. The higher the calcium carbonate content, the stronger the agglomeration of red clay particles in the soil samples.

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Effects of In-Situ Filler Loading vs. Conventional Filler and the Use of Retention-Related Additives on Properties of Paper

Materials ◽

10.3390/ma13225066 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5066

Author(s):

Maria Emiliana Fortună ◽

Andrei Lobiuc ◽

Lucian-Mihai Cosovanu ◽

Maria Harja

Keyword(s):

Mechanical Properties ◽

Calcium Carbonate ◽

Filler Loading ◽

Carbonate Content ◽

Sem Images ◽

Paper Properties ◽

Calcium Carbonate Content ◽

Optical And Mechanical Properties ◽

Filler Retention

In the present paper, aspects concerning the obtained and characterization of additive systems used for maximizing filler retention, and the effects on paper properties, were investigated. The effects of retention additives over properties of paper, containing fibers from in-situ loading (IS-CCP), were analyzed against the effects of additives over properties of paper containing fibers from conventional loading, obtained by the addition of calcium carbonate in precipitated form (CCP). The physico-mechanical properties were analyzed by various analyses and investigations: calcium carbonate content, X-ray diffraction, scanning electron microscopy (SEM) images, optical and mechanical properties, in order to develop the best systems of retention additives for obtaining higher retention loads for making paper with high content of nano-filler material. The obtained results reveal that at the same level of calcium carbonate content, all paper samples with in-situ loading had higher the optical and mechanical properties than the paper obtained by conventional loading in all cases the additives studied. For all studied properties, nanoparticles had a positively influence over paper properties.

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Opto‐electrochemical Dissolution Reveals Coccolith Calcium Carbonate Content

Angewandte Chemie International Edition ◽

10.1002/anie.202108435 ◽

2021 ◽

Author(s):

Minjun Yang ◽

Christopher Batchelor-McAuley ◽

Samuel Barton ◽

Rosalind E.M. Rickaby ◽

Heather A. Bouman ◽

...

Keyword(s):

Calcium Carbonate ◽

Carbonate Content ◽

Electrochemical Dissolution ◽

Calcium Carbonate Content

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A Novel Resorbable Composite Material Containing Poly(ester-co-urethane) and Precipitated Calcium Carbonate Spherulites for Bone Augmentation—Development and Preclinical Pilot Trials

Molecules ◽

10.3390/molecules26010102 ◽

2020 ◽

Vol 26 (1) ◽

pp. 102

Author(s):

Claudia Rode ◽

Ralf Wyrwa ◽

Juergen Weisser ◽

Matthias Schnabelrauch ◽

Marijan Vučak ◽

...

Keyword(s):

Composite Material ◽

Calcium Carbonate ◽

Bone Substitute ◽

Pilot Trial ◽

Carbonate Content ◽

Precipitated Calcium Carbonate ◽

Degradation Behaviour ◽

Biodegradable Composite ◽

Loss Of Mass

Polyurethanes have the potential to impart cell-relevant properties like excellent biocompatibility, high and interconnecting porosity and controlled degradability into biomaterials in a relatively simple way. In this context, a biodegradable composite material made of an isocyanate-terminated co-oligoester prepolymer and precipitated calcium carbonated spherulites (up to 60% w/w) was synthesized and investigated with regard to an application as bone substitute in dental and orthodontic application. After foaming the composite material, a predominantly interconnecting porous structure is obtained, which can be easily machined. The compressive strength of the foamed composites increases with raising calcium carbonate content and decreasing calcium carbonate particle size. When stored in an aqueous medium, there is a decrease in pressure stability of the composite, but this decrease is smaller the higher the proportion of the calcium carbonate component is. In vitro cytocompatibility studies of the foamed composites on MC3T3-E1 pre-osteoblasts revealed an excellent cytocompatibility. The in vitro degradation behaviour of foamed composite is characterised by a continuous loss of mass, which is slower with higher calcium carbonate contents. In a first pre-clinical pilot trial the foamed composite bone substitute material (fcm) was successfully evaluated in a model of vertical augmentation in an established animal model on the calvaria and on the lateral mandible of pigs.

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“In-situ” theories of loess formation and the significance of the calcium-carbonate content of loess

Earth-Science Reviews ◽

10.1016/0012-8252(71)90082-1 ◽

1971 ◽

Vol 7 (2) ◽

pp. 67-85 ◽

Cited By ~ 31

Author(s):

I.J. Smalley

Keyword(s):

Calcium Carbonate ◽

Carbonate Content ◽

Calcium Carbonate Content

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Studies in the absorption and excretion of certain minerals by poultry. III. The influence of different levels of dietary calcium upon the retention of calcium, phosphorus, carbonate and chloride

The Journal of Agricultural Science ◽

10.1017/s0021859600024023 ◽

1946 ◽

Vol 36 (4) ◽

pp. 283-288 ◽

Cited By ~ 2

Author(s):

Cyril Tyler

Keyword(s):

Calcium Carbonate ◽

Dietary Calcium ◽

Egg Laying ◽

Carbonate Content ◽

Phosphorus Excretion ◽

Calcium Carbonate Content ◽

High Calcium ◽

Calcium Phosphorus ◽

Different Levels

1. The daily retention of calcium, carbonate, phosphorus and chloride was studied using four birds and changing the calcium carbonate content of the ration every 5 days for 15 days.2. It was shown that high calcium diets result in a much lower retention of calcium and thin-shelled eggs are produced.3. Retention of calcium was higher in the laying than in the non-laying bird when calcium carbonate was fed.4. High calcium diets depressed the retention of phosphorus, and in one case the retention was negative, even when no eggs were laid. Laying birds gave negative values for retention because of the heavy phosphorus excretion associated with egg laying.5. High calcium diets also depressed the retention of chloride, and on occasion led to negative retention values.

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