Calcium Carbonate Research Articles

Taste Preferences in Broilers: Effect of Age, Delivery Matrix, and Number of Chickens per Pen on Selection and Consumption Behaviour

Due to substantial differences between studies, the understanding of avian taste perception remains incomplete. Also, studies on chicken taste preferences have mainly focused on measuring consumption differences, neglecting consumption behaviour patterns. This study investigated how age, the compound delivery matrix, and the number of birds per pen affect broiler chicken preferences and consumption behaviour, and established their preference values for four taste compounds. Ninety-six one-day-old male broiler chickens (Ross 308) were divided into two age groups (initial: days 7–23; final: days 26–42), with two compound delivery matrices (water or ground wheat) and two numbers of birds (one or two chickens per pen), following a 2 × 2 × 2 factorial design. Four taste compounds (sucrose, monosodium glutamate (MSG), L-lysine, and calcium carbonate) were tested at different concentrations. Preferences were assessed at 2, 4, and 8 h post-test, along with recording various behavioural parameters. Initial-stage birds showed higher (p < 0.001) preference values, time of approach (TA), number of bouts (NB), duration of bouts (DB), and number of pecks (NP) than final-stage birds. Birds exposed to a water matrix also exhibited higher (p < 0.001) preference and NB, while those exposed to a ground wheat matrix showed a higher (p < 0.001) NP. Pens with a pair of birds had a higher (p < 0.003) 2 h preference, TA, NB, DB, and NP, than pens with a single chicken. Chickens showed significant preference values for 100 mM sucrose at 2 h (p = 0.025), 150 mM MSG at 4 h (p = 0.026) and 8 h (p = 0.013), and 300 mM MSG at 2 h (p = 0.013). We concluded that all the variables evaluated influence broilers’ taste preferences and consumption behaviour during selection tests. Future studies should prioritize including chickens in the initial stage of the production cycle, testing them in pairs or groups, and delivering compounds via a liquid matrix.

Liming potential and characteristics of biochar produced from woody and non-woody biomass at different pyrolysis temperatures

Large amount of wastes are burnt or left to decompose on site or at landfills where they cause air pollution and nutrient leaching to groundwater. Waste management strategies that return these food wastes to agricultural soils recover the carbon and nutrients that would otherwise have been lost, enrich soils and improve crop productivity. The incorporation of liming materials can neutralize the protons released, hence reducing soil acidity and its adverse impacts to the soil environment, food security, and human health. Biochar derived from organic residues is becoming a source of carbon input to soil and provides multifunctional values. Biochar can be alkaline in nature, with the level of alkalinity dependent upon the feedstock and processing conditions. This study conducted a characterization of biochar derived from the pyrolysis process of eggplant and Acacia nilotica bark at temperatures of 300 °C and 600 °C. An analysis was conducted on the biochar kinds to determine their pH, phosphorus (P), as well as other elemental composition. The proximate analysis was conducted by the ASTM standard 1762-84, while the surface morphological features were measured using a scanning electron microscope. The biochar derived from Acacia nilotica bark exhibited a greater yield and higher level of fixed carbon while possessing a lower content of ash and volatile components compared to biochar derived from eggplant. The eggplant biochar exhibits a higher liming ability at 600 °C compared to the acacia nilotica bark-derived biochar. The calcium carbonate equivalent, pH, potassium (K), and phosphorus (P) levels in eggplant biochars increased as the pyrolysis temperature increased. The results suggest that biochar derived from eggplant could be a beneficial resource for storing carbon in the soil, as well as for addressing soil acidity and enhancing nutrients availability, particularly potassium and phosphorus in acidic soils.

Crayfish Waste-shells Integrated Valorization for Added Value Materials Production: Calcium Hydroxide, Calcium Carbonate, Chitin, Chitosan, and N-S co-doped Carbon Quantum Dots

Crayfish Waste-shells Integrated Valorization for Added Value Materials Production: Calcium Hydroxide, Calcium Carbonate, Chitin, Chitosan, and N-S co-doped Carbon Quantum Dots

An Approach to the Key Soil Physical Properties for Assessing Soil Compaction Due to Livestock Grazing in Mediterranean Mountain Areas

The selection of key soil physical properties (SPPs) for studying the impact of livestock treading is an unexplored research topic, especially in studies that analyze the influence of livestock management on the degradation process. The objective of this work was to demonstrate that the key SPPs for studying the impact of livestock treading depend on the objectives of the research and the environmental characteristics of the study site. This work used discriminant analysis to establish the most significant SPPs among the following: bulk density (BD), total porosity (P), field capacity (FC), infiltration capacity (IC), and aggregate stability (AS). Results showed that (1) IC and BD are the key properties for identifying the areas affected (bare patch) and unaffected (vegetated patch) by livestock treading, (2) none of the SPPs are significant under increasing stocking rates, and (3) BD is the key property for analyzing livestock impact with increasing stocking rate, using soil calcium carbonate content, slope exposure, and grass cover. We concluded that the relationship between physical soil degradation and stocking rate is not linear because it depends on environmental factors; therefore, to establish the key SPPs, it is necessary to take this fact into account.

Addition of calcium carbonate in the synthesis of flexible polyurethane foams

Within all their variability, foams constitute the largest segment in the polyurethane industry. Polyurethane is composed mainly of isocyanate (-N=C=O) and polyol (-OH) functional groups, presenting different characteristics by adding fillers. This polymer has a wide range of applications such as adhesives, coatings, varnishes, elastomers and foams. Aiming improvements in its thermal properties, calcium carbonate addition was investigated in proportions of 12.5%, 25% and 37.5% (w/w). This filler is widely used to change the properties of polymers, as it is easily found in nature and has a low cost. For the synthesis of polyurethane samples, isocyanate and polyol were reacted using "one shot" process. The obtained results demonstrated the change in the glass transition temperatures (Tg) of the material to higher values, which indicates a decrease in the mobility of the polymer chains. Also, an increase in decomposition temperature was observed via differential scanning calorimetry (DSC). With Fourier transform infrared spectroscopy (FTIR) analysis, it was possible to analyze that the material was successfully synthesized by the appearance of the characteristic bands of PU foams. Furthermore, with the addition of calcium carbonate, it was possible to identify the presence of two phases, which indicate that the material underwent changes in its crystallinity, identified through X-ray diffraction (XRD) analysis. Finally, it was possible to observe via optical microscopy (OM) analysis that the addition of filler significantly changed the morphology of the foams.

Discontinuous Shear Thickening of Suspensions of Magnetic Particles in Relation to the Polymer Coating on Their Surfaces

The phenomenon of discontinuous shear thickening (DST) is observed in suspensions of solid particles with a very high-volume fraction. It is characterized by an abrupt decrease in the shear rate for critical stress during a ramp of stress. This behavior can be reproduced in numerical simulations by introducing a local friction between two particles above a given local force. We present experimental results showing this DST behavior obtained with suspensions of magnetic (iron) and nonmagnetic (calcium carbonate) particles and different amounts of a superplasticizer molecule used in the cement industry. For both types of particles, the same behavior was observed with first an increase in critical stress with the amount of plasticizer followed by a decrease at higher concentrations but with a larger viscosity before critical stress was reached. At a low concentration of plasticizer, the low critical stress is interpreted by the local sliding of plasticizer molecules on the surface of particles. At higher concentrations, when total coverage is achieved, the critical stress is higher since it has to remove the molecules out of the surface. At still higher concentrations, the increase in viscosity is explained by the formation of multilayers of molecules on the surface of the particles. This interpretation is supported by the measurement of the adsorption isotherm of the plasticizer on the surface of the particles.

Reduction in Powder Wall Friction by an a-C:H:Si Film

The wall friction angle is an important parameter in powder flow. In a recent study for various powders, a reduction in the wall friction angle for steel was demonstrated by the application of an a-C:H:Si film on the steel surface. This work presents the results of a study of this effect in more detail regarding the influence of the powder material, the wall normal stress and the particle size of the powder for mass median diameters from 4 µm to approximately 150 µm. The wall friction angles were measured using a Schulze ring shear tester for three different powder materials: aluminum oxide, calcium carbonate and silicon carbide. The results showed little difference with respect to powder chemistry. For the coarser powders, the reduction in the wall friction angle due to the a-C:H:Si coating was highest (10° to 12°) and rather stress-independent, while for the fine and medium-size powders the reduction was lower and stress-dependent. With increasing wall normal stress, the reduction in the wall friction angle increased. These results can be explained by the friction reduction mechanism of a-C:H:Si, which requires a certain contact pressure for superficial graphitization.

Modification of Living Diatom, Thalassiosira weissflogii, with a Calcium Precursor through a Calcium Uptake Mechanism: A Next Generation Biomaterial for Advanced Delivery Systems.

The diatom's frustule, characterized by its rugged and porous exterior, exhibits a remarkable biomimetic morphology attributable to its highly ordered pores, extensive surface area, and unique architecture. Despite these advantages, the toxicity and nonbiodegradable nature of silica-based organisms pose a significant challenge when attempting to utilize these organisms as nanotopographically functionalized microparticles in the realm of biomedicine. In this study, we addressed this limitation by modulating the chemical composition of diatom microparticles by modulating the active silica metabolic uptake mechanism while maintaining their intricate three-dimensional architecture through calcium incorporation into living diatoms. Here, the diatom Thalassiosira weissflogii was chemically modified to replace its silica composition with a biodegradable calcium template, while simultaneously preserving the unique three-dimensional (3D) frustule structure with hierarchical patterns of pores and nanoscale architectural features, which was evident by the deposition of calcium as calcium carbonate. Calcium hydroxide is incorporated into the exoskeleton through the active mechanism of calcium uptake via a carbon-concentrating mechanism, without altering the microstructure. Our findings suggest that calcium-modified diatoms hold potential as a nature-inspired delivery system for immunotherapy through antibody-specific binding.

Enhanced Osteosarcoma Immunotherapy via CaCO3 Nanoparticles: Remodelling Tumour Acidic and Immune Microenvironment for Photodynamic Therapy.

Osteosarcoma (OS) is a "cold" tumour enriched in noninflammatory M2 phenotype tumour-associated macrophages (TAMs), which limits the efficacy of immunotherapy. The acidic tumour microenvironment (TME), generated by factors such as excess hydrogen (H+) ions and high lactate levels, activates immunosuppressive cells (e.g., M2 phenotype TAMs), further promoting a suppressive tumour immune microenvironment (TIME). Therefore, a multitarget synergistic combination strategy that neutralizes the acidic TME and reprograms TAMs can be beneficial for OS therapy. Here, a calcium carbonate (CaCO3)/polydopamine (PDA)-based nanosystem (A-NPs@(SHK+Ce6)) was developed for the targeted codelivery of the photosensitizer Ce6 and shikonin (SHK) to OS tumours via the bone-targeting ability of alendronate sodium (ALN). CaCO3 nanoparticles were used to neutralize H+ ions and alleviate the suppressive TIME, and the loaded SHK not only synergized with photodynamic therapy (PDT) by promoting reactive oxygen species (ROS) generation and enhancing immunogenic cell death (ICD) but also inhibited lactate production, further reversing the acidic TME and repolarizing TAMs to consequently lead to enhanced PDT-induced tumour suppression and comprehensive beneficial effects on antitumour immune responses, including the promotion of CD8+ T-cell infiltration and regulatory T-cell (Treg) suppression. Importantly, A-NPs@(SHK+Ce6), in combination with programmed cell death protein 1 (PD-1) checkpoint blockade, showed a remarkable ability to eliminate distant tumours and promote long-term immune memory function to protect against rechallenged tumours. This work presents a novel multiple-component combination strategy that coregulates the acidic TME and TAM polarization to reprogram the TIME. This article is protected by copyright. All rights reserved.

Application and mechanism of carbonate material in the treatment of heavy metal pollution: a review.

Among the many heavy metal pollution treatment agents, carbonate materials show strong flexibility and versatility by virtue of their high adsorption capacity for heavy metals and the characteristics of multiple and simple modification methods. It shows good potential for development. This review summarizes the application of carbonate materials in the treatment of heavy metal pollution according to the research of other scholars. It mainly relates to the application of surface-modified, activated, and nano-sized carbonate materials in the treatment of heavy metal pollution in water. Natural carbonate minerals and composite carbonate minerals solidify and stabilize heavy metals in soil. Solidification of heavy metals in hazardous waste solids is by MICP. There are four aspects of calcium carbonate oligomers curing heavy metals in fly ash from waste incineration. The mechanism of treating heavy metals by carbonate in different media was discussed. However, in the complex environment where multiple types of pollutants coexist, questions on how to maintain the efficient processing capacity of carbonate materials and how to use MICP to integrate heavy metal fixation and seepage prevention in solid waste base under complex and changeable natural environment deserve our further consideration. In addition, the use of carbonate materials for the purification of trace radioactive wastewater and the safe treatment of trace radioactive solid waste are also worthy of further exploration.

Ecological Studies on the Soil and Vegetation of Krusadi Group of Islands in the Gulf of Manaar

The account presents the plant ecology with a description of soils and other related features of the Krusadi group of islands situated in the Gulf of Manaar approximately between 9°14'-9°15'N and 79°10.5'-79°14.5' E. Data on pH, organic matter contents, total soluble salts, sodium chloride contents and calcium carbonate contents in the soils of different habitats are presented in tabular form and an attempt made to correlate vegetation with the soil features. A classification of vegetation situations rather than strictly vegetation type has been brought out and comparison made with the main neighbouring island of Rameswaram with similar climate. The paper includes a vegetation map of the area prepared during the field work.

Removal of Organic Materials from Mytilus Shells and Their Morphological and Chemical-Physical Characterisation

A simple and effective method to eliminate the organic component from mussel shells is presented. It is based on the use of hot hydrogen peroxide. Mollusc shells are composite materials made of a calcium carbonate matrix with different polymorphs and numerous biomacromolecules. The described method was used on mussel shells, but it is generalisable and allows the complete removal of these organic components, without altering the inorganic part. Specimens were kept in a H2O2 40% bath for few hours at 70 °C. The organic layers found on the faces of the shells were peeled away in this way, and biomacromolecules were degraded and removed. Their fragments are soluble in aqueous solution. This easily permits the chemical-physical characterisation and the study of the microstructure. The quality of calcite and aragonite microcrystals of biogenic origin is very high, superior to that of materials of geological or synthetic origin. This may suggest various industrial applications for them. Calcium carbonate is a useful precursor for cements and other building materials, and the one obtained in this way is of excellent quality and high purity.

Experimental study of fouling characteristics of CaCO3 precipitated crystal scale mixed with different particles in an alternating magnetic field environment

This paper is to study the effect of CaCO3 precipitated crystal scale mixed with different particles on the scaling characteristics under the action of electromagnetic field. The simulation of industrial field experiments, based on the electromagnetic water treatment dynamic experimental bench, change the type of particles, concentration, magnetic field strength, according to the experimental results of the thermal resistance and scale inhibition rate curve under different working conditions, through the scanning electron microscope microscopy analysis of the fouling samples, to study the effect of CaCO3 fouling mixed with different particles in the role of the magnetic field on the effect of the law on the deposition characteristics.The results show that: electromagnetic field on MgO particles dirt and CaCO3 dirt deposition have inhibition effect; CaCO3 and different concentrations of CaCO3 crystalline particles mixed, CaCO3 particles, the more the electromagnetic field on the formation of CaCO3 precipitation scale inhibition effect is not obvious; CaCO3 precipitation scale and MgO particles mixed in the magnetic field can significantly enhance the effect of the field of the inhibition of the scale, magnetic field Under the action of the magnetic field, as the content of MgO particles increases, the scale inhibition effect on the dirt is first enhanced and then weakened until it tends to be about 0. Scanning electron microscopy analyses showed that the morphology and degree of aggregation of calcium carbonate fouling crystals were influenced by MgO particles under the action of electromagnetic fields, and CaCO3 fouling was transformed from regular ortho-hexahedra to acicular aragonite and amorphous CaCO3, which made the stripping phenomenon more significant.Comprehensive experimental results and scanning electron microscopy analyses of fouling samples show that the mixture of CaCO3 solution with a small amount of MgO particles can be an effective means to inhibit the precipitation of crystalline fouling under the environment of alternating electromagnetic field. This study provides theoretical guidance for the application of alternating magnetic field in the future, and provides new ideas and methods for solving the problem of crystalline fouling in industry.

Hollow fiber membrane governed microjet flow regime for confined crystallization of large‐sized crystal aggregates

AbstractConfined crystallization can realize controllable nucleation and growth of crystals with targeted morphologies in a restricted region. Here, we achieved confined reactive crystallization within a novel micro columnar jet flow regime constructed by the hollow fiber membrane. The interface of the jet flow corresponds as the restricted region for reactive crystallization, and the large‐sized calcium carbonate (CaCO3) crystals aggregates with millimeter length can ordered and self‐assembly grow along the boundary of this region. Formation mechanism of the jet flow was systematically investigated by real‐time observation and force analysis. The detected detachment‐regrowth cycle during the experiments furtherly uncovered the potential for continuous operation. Linear (diameter: 0.12–0.3 mm; length: 1.5–3.1 mm) and lamellar crystals (thickness of 200–300 nm and average area of 0.21 mm2) were obtained by effectively manipulating the diameter and effective length of jet flow.

Maximizing microcalcification detectability in low-dose dedicated cone-beam breast CT: parallel cascades-based theoretical analysis.

We aim to determine the combination of X-ray spectrum and detector scintillator thickness that maximizes the detectability of microcalcification clusters in dedicated cone-beam breast CT. A cascaded linear system analysis was implemented in the spatial frequency domain and was used to determine the detectability index using numerical observers for the imaging task of detecting a microcalcification cluster with 0.17mm diameter calcium carbonate spheres. The analysis considered a thallium-doped cesium iodide scintillator coupled to a complementary metal-oxide semiconductor detector and an analytical filtered-back-projection reconstruction algorithm. Independent system parameters considered were the scintillator thickness, applied X-ray tube voltage, and X-ray beam filtration. The combination of these parameters that maximized the detectability index was considered optimal. Prewhitening, nonprewhitening, and nonprewhitening with eye filter numerical observers indicate that the combination of 0.525 to 0.6mm thick scintillator, 70kV, and 0.25 to 0.4mm added copper filtration maximized the detectability index at a mean glandular dose (MGD) of 4.5mGy. Using parallel cascade systems' analysis, the combination of parameters that could maximize the detection of microcalcifications was identified. The analysis indicates that a harder beam than that used in current practice may be beneficial for the task of detecting microcalcifications at an MGD suitable for breast cancer screening.

Removal and recovery of phosphorus by a long–term stabilized amorphous calcium carbonate

Phosphorus is a non–renewable resource that guarantees food production, while excessive phosphorus discharge leads to water eutrophication. Phosphorus removal/recovery could help improve water quality and ensure food security. In this contribution, silica–stabilized amorphous calcium carbonates (Si–ACC) were prepared and used to remove/recover phosphate in sludge and domestic sewage. The mechanisms were investigated via kinetic and isothermal adsorption studies and XRD, TEM, Raman, and FT–IR characterization. The results showed that the homogeneously distributed silica successfully inhibited ACC transformation and helped Si–ACC keep the amorphous feature within 680 d. During phosphorus adsorption, Si–ACC quickly transformed into calcite within 5 min and reacted with phosphorus to generate polycrystalline hydroxylapatite within 60 min. The recovered product possessed a maximum specific surface area (SSA) of 209 m2/g and available phosphorus content of 18.0 %, suggesting that Si–ACC was a promising phosphorus recovery material and the recovered product could be a potential phosphate fertilizer.

Mechanical Characterization of Hybrid Bagasse/Eggshell/E-glass Fiber-based Polyester Composite

Currently, numerous researchers, scientists, and industrialists are drawn towards utilizing natural fillers rather than synthetic ones because of their environmentally-friendly characteristics, lower density per unit volume and favorable mechanical attributes. Several studies have demonstrated that using organic filler in polyester matrix composites, instead of disposing of them in landfills, has various advantages. The current study focuses on the investigation of the mechanical characteristics of composite material made from a combination of bagasse, eggshell, and e-glass fibers exhibit characteristics such as strength under tension, strength under bending, resistance to indentation, and mass per unit volume. Different weight percentages of eggshell/bagasse were used to make the material using the hand lay-up technique (3wt%, 6wt%, 9wt%, and 12wt%), with 19wt% of glass fiber mixed in the resin. The use of inorganic fillers like calcium carbonate, a non-renewable mineral that may be expensive and environmentally hazardous to extract and process, is being reduced in favor of organic fillers like eggshell and bagasse, which are inexpensive and readily available. Specimens were generated by interposing fiber waste amidst chopped strand glass fiber mats, with variations in the bagasse, eggshell and polyester content, while keeping the amount of E-glass fiber constant. Afterward, the specimens were trimmed to the appropriate dimensions and subjected to analysis with a universal apparatus. The research showed that enhancing the quantity of bagasse/eggshell fiber within the hybrid composite resulted in an enhancement of its mechanical characteristics. The best reinforcement effect was observed in a hybrid composite with 6% bagasse/eggshell fiber.

Unveiling the Geological Significance and Industrial Application of Limestone: A Comprehensive Review

Limestone emerges as a fundamental component within sedimentary rock formations, which provides important information about previous geological eras and environmental circumstances. It retains fossils and remnants of extinct living forms because it mostly contains calcium carbonate. These deposits are used as traces of freshwater, marine, and terrestrial habitats from the past. Furthermore, variations in the creation of limestone provide hints about past geological events like tectonic activity and sea level shifts. Scientists can reconstruct previous ecosystems, temperatures, and evolutionary patterns by analyzing limestone, which helps us better comprehend Earth's environmental dynamics and history over millions of years. Its versatility extends beyond its geological significance, and its primary uses are in the manufacturing of steel and cement, as well as in the purification of wastewater and the processes involved in the production of bread and sugar. Limestone is also essential for supporting the carbon cycle and improving soil health in agricultural settings. In the review paper, we endeavored to conduct additional research to comprehend the intricacies of geology and the industrial application of limestone, as well as the need for interdisciplinary collaboration, sustainable practices, and cutting-edge technologies to leverage mineral resources for industrial growth. To be effective, it is essential. This study concludes with a strong call to action, imploring stakeholders to emphasize sustainable practices and encourage interdisciplinary collaboration while using limestone. By adhering to these guidelines, we can maximize the benefits of this priceless natural resource for both industrial use and environmental sustainability while also protecting it for future generations.

Parotid duct sialolithiasis in three Caspian miniature horses

AbstractThree Caspian miniature horses, exhibiting facial swellings, were examined in Alborz province. Physical examinations denoted sialolithiasis in two patients, and arose suspicion of the same condition in the third patient. The sialoliths were removed using a transcutaneous surgical approach with standing sedation using xylazine (1 mg/kg, intravenously) and local anaesthesia with lidocaine (5–10 mL) in all three patients. In Case 1, multiple pieces of stone were excised from the left parotid duct using a transcutaneous approach. In Case 2, a single oval‐shaped stone (44 g) was excised from the right parotid duct with the same technique as mentioned above. Case 3 presented a 1‐g amorphous stone partially obstructing the right parotid duct, resulting in cyst formation on the right aspect of the face. Chemical analysis identified calcium carbonate as the primary component. Given the distribution of horses in Iran, accurate estimation of the frequency of sialolithiasis is quite challenging, and numerous cases are overlooked.

Acidification in cement paste in which clinker is partially replaced with limestone or silica

This paper examines the acid resistance of cement pastes where a portion of the cement clinker is replaced with limestone (LS or calcium carbonate, CaCO3) or ground silica (GS). Specifically, the work is intended to better understand the acid resistance of ASTM C595 IL cement as compared with ASTM C150 cement. The performance of OPC, OPC + GS, and OPC + LS systems were tested in sulfuric acid baths where the pH was held constant at 2.0 and 3.0 using an automated setup that uses titration to add acid. The degradation of the cement paste was measured as a function of time. Thermogravimetric analysis (TGA) was used to quantify changes in the calcium hydroxide (Ca(OH)2) and calcium carbonate (CaCO3) contents of the paste. In addition, the flexural strength of the cement paste specimens was measured. Results indicate that the dissolved sulfate and calcium concentrations due to acidification were not noticeably different for the OPC + GS and OPC + LS mixtures exposed to the same pH. However, as expected, differences were observed between the samples immersed in the solution of pH∼2 and pH∼3 sulfuric acid with the lower pH corresponding to more severe deterioration. TGA results showed that Ca(OH)2 is more susceptible to acid attack than limestone as evidenced by the larger Ca(OH)2 and sulfuric acid consumption in samples immersed at pH∼2. The additional acid consumption that is beyond the consumption of Ca(OH)2 can be explained by the acid attack of other hydration products such as CSH and unreacted cement phases. This results in a significant B3B flexural strength loss for the samples immersed in a pH∼2 as compared to those in the pH∼3 solution. The results demonstrated that the performance of ASTM C595 IL cements was promising and comparable with ASTM C150 cements.