Consequences of omitting some important factors in the environmental analyses of commercial sodium silicate/sodium hydroxide use for alkaline activation in the light of comparison with cement-based composites.

Alkali-activated materials (AAMs) based on various waste precursors were considered mostly as a sustainable alternative to Portland cement-based composites to date. However, a narrow focus on carbon dioxide savings in the environmental assessment of AAMs may not be sufficient to achieve a truly sustainable solution. Therefore, this paper provides a detailed insight into midpoint impact categories related to the production of AAMs based on waste precursors and conventional activators, as compared with common cement-based materials. The obtained results point to a higher environmental load of AAMs in several categories, such as ozone layer depletion, primary resource consumption, and terrestrial and aquatic ecotoxicity. In a hypothetical scenario, it is demonstrated that 10 % replacement of global concrete production by AAMs may result in notably increased emissions of ozone depletion substances (+35 %) and damage to the aquatic environment (+ 40 %). The risk for human health can then be higher. As for the aquatic environment, eutrophication can also lead to a significant increase in indirect emissions of CH4 and N2O having a high impact on the greenhouse effect. Hence, the importance of robust interdisciplinary research in the environmental assessment of AAMs should be emphasized, together with the need to use alternative alkaline substances, which would be more environment-friendly than conventional activators.

Assessment of Clayey Freshwater Sediments as Suitable Precursors for Alkaline Activation.

One of the biggest challenges in the construction industry in recent times is the mitigation of the environmental impact of this sector, the reduction in dependence on primary raw materials, and the reduction in CO2 production while maintaining functional properties. Alkaline activation of a number of waste products represents a promising way to achieve the above-mentioned goals, but the availability of a number of waste products changes over time, especially in Europe. While freshwater sediments were in the past widely utilized as an agricultural fertilizer, recent precautions have significantly decreased such application, and thus new destinations must be delivered. To explore the potential of freshwater sediments, select samples from various locations were subjected to detailed characterization to verify the applicability of the material for alkali activation. As recognized, the selected sediments contain a substantial volume of desired mineralogical compounds that can serve, after 900 °C curing, as suitable precursors. Such samples have consequently activated the mixture of alkaline activators to obtain dense structures and were subjected to detailed investigation aimed at understanding the mechanical parameters. The obtained mechanical results ranging between 14.9 MPa and 36.8 MPa reveal the engineering potential of sediments for valorization through alkali activation and outline new research challenges in this area.

Ecotoxicity of Caffeine as a Bio-Protective Component of Flax-Fiber-Reinforced Epoxy-Composite Building Material.

Caffeine is a verified bio-protective substance in the fight against the biodegradation of cellulose materials, but its ecotoxicity in this context has not yet been studied. For this reason, the ecotoxicity of flax-fiber-reinforced epoxy composite with or without caffeine was tested in the present study. Prepared samples of the composite material were tested on freshwater green algal species (Hematococcus pluvialis), yeasts (Saccharomyces cerevisae), and crustacean species (Daphnia magna). Aqueous eluates were prepared from the studied material (with caffeine addition (12%) and without caffeine and pure flax fibers), which were subjected to chemical analysis for the residues of caffeine or metals. The results indicate the presence of caffeine up to 0.001 mg/L. The eluate of the studied material was fully toxic for daphnids and partially for algae and yeasts, but the presence of caffeine did not increase its toxicity statistically significantly, in all cases. The final negative biological effects were probably caused by the mix of heavy metal residues and organic substances based on epoxy resins released directly from the tested composite material.

Pre-mandibular pharyngeal pouches in early non-teleost fish embryos.

The vertebrate pharynx is a key embryonic structure with crucial importance for the metameric organization of the head and face. The pharynx is primarily built upon progressive formation of paired pharyngeal pouches that typically develop in post-oral (mandibular, hyoid and branchial) domains. However, in the early embryos of non-teleost fishes, we have previously identified pharyngeal pouch-like outpocketings also in the pre-oral domain of the cranial endoderm. This pre-oral gut (POG) forms by early pouching of the primitive gut cavity, followed by the sequential formation of typical (post-oral) pharyngeal pouches. Here, we tested the pharyngeal nature of the POG by analysing expression patterns of selected core pharyngeal regulatory network genes in bichir and sturgeon embryos. Our comparison revealed generally shared expression patterns, including Shh, Pax9, Tbx1, Eya1, Six1, Ripply3 or Fgf8, between early POG and post-oral pharyngeal pouches. POG thus shares pharyngeal pouch-like morphogenesis and a gene expression profile with pharyngeal pouches and can be regarded as a pre-mandibular pharyngeal pouch. We further suggest that pre-mandibular pharyngeal pouches represent a plesiomorphic vertebrate trait inherited from our ancestor's pharyngeal metameric organization, which is incorporated in the early formation of the pre-chordal plate of vertebrate embryos.

Experimental and Environmental Analysis of High-Strength Geopolymer Based on Waste Bricks and Blast Furnace Slag.

The rationalization of material flows, together with the utilization of waste raw materials for the production of alternative binders, became a very attractive topic during the last decades. However, the majority of designed materials can be used as a replacement for low-performance products. In this work, the waste materials (brick powder and blast furnace slag) are valorized through geopolymerization to design high-performance material as an alternative to high-performance concrete. Designed mixtures activated by sodium silicate and waste-originated alkali solution are characterized by the meaning of the chemical and mineralogical composition, evolution of hydration heat, and mechanical strength test. To contribute to the understanding of the environmental consequences and potential benefits, the carbon footprint and embodied energy analysis are provided. Obtained results highlight the potential of end-of-life bricks for the design of high-performance composites if mixed together with more reactive precursors. Here, even values over 60 MPa in compressive strength can be achieved with the dominant share of low-amorphous brick powder. The higher crystalline portion of brick powder may lead to the reduction of drying shrinkage and preservation of flexural strength to a greater extent compared to used slag. Performed environmental analysis confirmed the CO2 emission savings; however, the embodied energy analysis revealed a huge impact of using alkaline activators.

Ancient vertebrate dermal armor evolved from trunk neural crest.

Bone is an evolutionary novelty of vertebrates, likely to have first emerged as part of ancestral dermal armor that consisted of osteogenic and odontogenic components. Whether these early vertebrate structures arose from mesoderm or neural crest cells has been a matter of considerable debate. To examine the developmental origin of the bony part of the dermal armor, we have performed in vivo lineage tracing in the sterlet sturgeon, a representative of nonteleost ray-finned fish that has retained an extensive postcranial dermal skeleton. The results definitively show that sterlet trunk neural crest cells give rise to osteoblasts of the scutes. Transcriptional profiling further reveals neural crest gene signature in sterlet scutes as well as bichir scales. Finally, histological and microCT analyses of ray-finned fish dermal armor show that their scales and scutes are formed by bone, dentin, and hypermineralized covering tissues, in various combinations, that resemble those of the first armored vertebrates. Taken together, our results support a primitive skeletogenic role for the neural crest along the entire body axis, that was later progressively restricted to the cranial region during vertebrate evolution. Thus, the neural crest was a crucial evolutionary innovation driving the origin and diversification of dermal armor along the entire body axis.

Structural Performance of Lightweight Aggregate Concrete Reinforced by Glass or Basalt Fiber Reinforced Polymer Bars.

Lightweight aggregate concrete (LWC) and fiber reinforced polymer (FRP) reinforcement are potentially more sustainable alternatives to traditional steel-reinforced concrete structures, offering several important benefits. To further the knowledge in this area, the physical-mechanical properties of LWC produced with 0%, 50%, and 100% expanded clay aggregate were assessed. Subsequently, the flexural behavior of LWC beams reinforced with steel reinforcement and glass and basalt FRP bars was tested. The results of the experimental program allowed quantifying of the effect of expanded clay aggregate incorporation on LWC properties. The use of FRP reinforcement was also compared to steel-reinforced concrete beam behavior. The results of this study can provide additional support for the use of innovative materials such as LWA and FRP reinforcement.

Ecotoxicity and Biodegradation of Sustainable Environment-Friendly Bone-Glue-Based Adhesive Suitable for Insulation Materials.

Bone glue with sodium lignosulfonate is a protein-based adhesive. Their combination leads to strong binding necessary for the achievement of adhesive properties. However, biodegradation and ecotoxicity of materials composed of bone glue and sodium lignosulfonate has never been studied before. In this paper, the biodegradation potential of the mixture of bone glue, lignosulfonate and rape straw modified by water or NaOH on an agar test with aerial molds and in acute aquatic tests with mustard, yeasts, algae and crustaceans was analyzed. Epoxy resin as an ecologically unfriendly binder was used as a negative control and pure rape straw as a background. The results indicated that all samples were covered by molds, but the samples containing straw treated by NaOH showed lower biodegradability. The ecotoxicological effects varied among the applied model organisms. Artemia salina was not able to survive and S. alba could not prolong roots in the eluates of all samples (100% inhibition). Freshwater algae (D. subspicatus) were not significantly affected by the samples (max. 12% inhibition, max. 16% stimulation). The biomass of yeasts (S. cerevisae) was strongly stimulated in the presence of eluates in a comparison to control (max. 38% stimulation).

Waste brick dust as a prospective eco-friendly alternative component of artificial soils for ecotoxicological studies.

Current artificial soils for ecotoxicological studies contain non-renewable materials that must be mined, and their production and processing consume a lot of energy and generate a significant amount of carbon dioxide (CO2). In this paper, waste brick dust is proposed as an alternative to calcium carbonate (CaCO3), which is used for pH adjustment of the Organization for Economic Co-operation and Development (OECD) soils. The artificial soils containing brick dust are contaminated with boric acid as a reference substance in the concentration range of 100-500 mg/kg and studied in the tests with enchytraeids (E. crypticus), springtails (F. candida), and plants (L. sativa and B. napus). Experimental results shows the suitability of replacing calcium carbonate with waste brick dust, as neither toxicity nor ability of model organisms to inhabit the analyzed soil is found. A comparison with the standard OECD soil does not reveal any substantial differences between the parameters (survival, reproduction, and root elongation) of the applied ecotoxicological tests. The brick dust as waste material is found to have a lower carbon footprint than CaCO3, while a similar amount of water is necessary for the adjustment of tests with both kinds of artificial soil. The waste brick dust can be considered as a suitable eco-friendly alternative to CaCO3 in artificial soils for ecotoxicological studies.

Bond Behavior of FRP Bars in Lightweight SCC under Direct Pull-Out Conditions: Experimental and Numerical Investigation.

In recent decades, lightweight aggregate concrete (LWC) became a popular building material due to its desired properties. However, various attributes of LWC, such as bond behavior of used reinforcing, have not been described thoroughly. In this regard, LWC produced with 0%, 50%, and 100% expanded clay aggregate was designed, and the physical-mechanical properties were assessed for material characterization. Subsequently, the bond behaviors of LWC reinforced with steel, glass fiber reinforced polymer (GFRP), and basalt fiber reinforced polymer (BFRP) bars were evaluated by pull-out tests. The results of the experimental program allowed the effects of expanded clay aggregate incorporation on LWC properties to be quantified. The bond strength of BFRP bars was not affected by the replacement of coarse aggregate by expanded clay aggregate, whilst the GFRP bars showed lower bond strength values of LWC specimens. Contrarily, in the case of steel bars, both the bond strength and bond stiffness were higher for LWC specimens than for those of normal concrete. Finite element software ATENA 3D was used for simulation of the bond behavior of LWC, and the model validated by the experimental results referred to reasonably corresponding outputs.

Environmental Consequences of Rubber Crumb Application: Soil and Water Pollution.

End-of-life tires are utilized for various purposes, including sports pitches and playground surfaces. However, several substances used at the manufacture of tires can be a source of concerns related to human health or environment's adverse effects. In this context, it is necessary to map whether this approach has the desired effect in a broader relation. While the negative effects on human health were investigated thoroughly and legislation is currently being revisited, the impact on aquatic or soil organisms has not been sufficiently studied. The present study deals with the exposure of freshwater and soil organisms to rubber crumb using the analysis of heavy metal and polycyclic aromatic hydrocarbon concentrations. The obtained results refer to substantial concerns related to freshwater contamination specifically, since the increased concentrations of zinc (7 mg·L-1) and polycyclic aromatic hydrocarbons (58 mg·kg-1) inhibit the growth of freshwater organisms, Desmodesmus subspicatus, and Lemna minor in particular. The performed test with soil organisms points to substantial concerns associated with the mortality of earthworms as well. The acquired knowledge can be perceived as a roadmap to a consistent approach in the implementation of the circular economy, which brings with it a number of so far insufficiently described problems.

Effects of Secondary Porosity on Microstructure and Mechanical Properties of SAP-Containing Lime-Based Plasters.

Despite the many benefits associated with the utilization of superabsorbent polymers (SAPs), several drawbacks have been reported. In particular, the effect of SAPs on microstructure, together with its consequences for mechanical properties, is not fully understood yet for some composite materials. This study analyzes the role of SAPs in the formation of the microstructure of lime composites, taking into account their chemical composition. The obtained experimental results show that the particle size and cross-linking density of used SAPs are crucial parameters affecting both the microstructure and mechanical performance of the analyzed composites. Coarser SAPs with low cross-linking density in the dosage of 0.5 and 1 wt.% are found as the most suitable solution, leading even to a slight improvement of mechanical parameters. The secondary porosity formed by swelled hydrogels is identified as a very significant factor since hydrogel-filled voids do not contribute to the strength parameters. The formation of the affected zone around SAP cores depends on the chemical composition of SAPs considerably as the higher cross-linking density influences the desorption rate. Based on achieved results, utilization of SAPs in building materials should be studied at a more detailed level with particular importance on the definition of SAP-related voids and affected zone around SAP particles.

Efficient CRISPR Mutagenesis in Sturgeon Demonstrates Its Utility in Large, Slow-Maturing Vertebrates.

In the last decade, the CRISPR/Cas9 bacterial virus defense system has been adapted as a user-friendly, efficient, and precise method for targeted mutagenesis in eukaryotes. Though CRISPR/Cas9 has proven effective in a diverse range of organisms, it is still most often used to create mutant lines in lab-reared genetic model systems. However, one major advantage of CRISPR/Cas9 mutagenesis over previous gene targeting approaches is that its high efficiency allows the immediate generation of near-null mosaic mutants. This feature could potentially allow genotype to be linked to phenotype in organisms with life histories that preclude the establishment of purebred genetic lines; a group that includes the vast majority of vertebrate species. Of particular interest to scholars of early vertebrate evolution are several long-lived and slow-maturing fishes that diverged from two dominant modern lineages, teleosts and tetrapods, in the Ordovician, or before. These early-diverging or "basal" vertebrates include the jawless cyclostomes, cartilaginous fishes, and various non-teleost ray-finned fishes. In addition to occupying critical phylogenetic positions, these groups possess combinations of derived and ancestral features not seen in conventional model vertebrates, and thus provide an opportunity for understanding the genetic bases of such traits. Here we report successful use of CRISPR/Cas9 mutagenesis in one such non-teleost fish, sterlet Acipenser ruthenus, a small species of sturgeon. We introduced mutations into the genes Tyrosinase, which is needed for melanin production, and Sonic hedgehog, a pleiotropic developmental regulator with diverse roles in early embryonic patterning and organogenesis. We observed disruption of both loci and the production of consistent phenotypes, including both near-null mutants' various hypomorphs. Based on these results, and previous work in lamprey and amphibians, we discuss how CRISPR/Cas9 F0 mutagenesis may be successfully adapted to other long-lived, slow-maturing aquatic vertebrates and identify the ease of obtaining and injecting eggs and/or zygotes as the main challenges.

The conundrum of pharyngeal teeth origin: the role of germ layers, pouches, and gill slits.

There are several competing hypotheses on tooth origins, with discussions eventually settling in favour of an 'outside-in' scenario, in which internal odontodes (teeth) derived from external odontodes (skin denticles) in jawless vertebrates. The evolution of oral teeth from skin denticles can be intuitively understood from their location at the mouth entrance. However, the basal condition for jawed vertebrates is arguably to possess teeth distributed throughout the oropharynx (i.e. oral and pharyngeal teeth). As skin denticle development requires the presence of ectoderm-derived epithelium and of mesenchyme, it remains to be answered how odontode-forming skin epithelium, or its competence, were 'transferred' deep into the endoderm-covered oropharynx. The 'modified outside-in' hypothesis for tooth origins proposed that this transfer was accomplished through displacement of odontogenic epithelium, that is ectoderm, not only through the mouth, but also via any opening (e.g. gill slits) that connects the ectoderm to the epithelial lining of the pharynx (endoderm). This review explores from an evolutionary and from a developmental perspective whether ectoderm plays a role in (pharyngeal) tooth and denticle formation. Historic and recent studies on tooth development show that the odontogenic epithelium (enamel organ) of oral or pharyngeal teeth can be of ectodermal, endodermal, or of mixed ecto-endodermal origin. Comprehensive data are, however, only available for a few taxa. Interestingly, in these taxa, the enamel organ always develops from the basal layer of a stratified epithelium that is at least bilayered. In zebrafish, a miniaturised teleost that only retains pharyngeal teeth, an epithelial surface layer with ectoderm-like characters is required to initiate the formation of an enamel organ from the basal, endodermal epithelium. In urodele amphibians, the bilayered epithelium is endodermal, but the surface layer acquires ectodermal characters, here termed 'epidermalised endoderm'. Furthermore, ectoderm-endoderm contacts at pouch-cleft boundaries (i.e. the prospective gill slits) are important for pharyngeal tooth initiation, even if the influx of ectoderm via these routes is limited. A balance between sonic hedgehog and retinoic acid signalling could operate to assign tooth-initiating competence to the endoderm at the level of any particular pouch. In summary, three characters are identified as being required for pharyngeal tooth formation: (i) pouch-cleft contact, (ii) a stratified epithelium, of which (iii) the apical layer adopts ectodermal features. These characters delimit the area in which teeth can form, yet cannot alone explain the distribution of teeth over the different pharyngeal arches. The review concludes with a hypothetical evolutionary scenario regarding the persisting influence of ectoderm on pharyngeal tooth formation. Studies on basal osteichthyans with less-specialised types of early embryonic development will provide a crucial test for the potential role of ectoderm in pharyngeal tooth formation and for the 'modified outside-in' hypothesis of tooth origins.

The remarkable dynamics in the establishment, rearrangement, and loss of dentition during the ontogeny of the sterlet sturgeon.

BACKGROUND: Sturgeons belong to an early-branching lineage often used as a proxy of ancestor-like traits of ray-finned fishes. However, many features of this lineage, such as the transitory presence and the eventual loss of dentition, exemplify specializations that, in fact, provide important information on lineage-specific evolutionary dynamics. RESULTS: Here, we introduce a detailed overview of the dentition during the development of the sterlet sturgeon. The dentition is composed of tooth fields at oral, palatal, and anterior pharyngeal regions. Oral fields are single-rowed, non-renewed and are shed early. Palatal and pharyngeal fields are multi-rowed and renewed from the adjacent superficial epithelium without the presence of the successional dental lamina. The early loss of oral fields and subsequent establishment of palatal and pharyngeal fields leads to a translocation of the functional dentition from the front to the rear of the oropharyngeal cavity until the eventual loss of all teeth. CONCLUSIONS: Our survey shows the sterlet dentition as a dynamic organ system displaying differential composition at different time points in the lifetime of this fish. These dynamics represent a conspicuous feature of sturgeons, unparalleled among extant vertebrates, and appropriate to scrutinize developmental and evolutionary underpinnings of vertebrate odontogenesis.

Utilization of Crushed Pavement Blocks in Concrete: Assessment of Functional Properties and Environmental Impacts.

Production of concrete is connected to extensive energy demands, greenhouse gases production or primary sources depletion. Reflecting current economical, social, or environmental trends, there is strong pressure on mitigation these requirements and impacts. The exploitation of secondary- or waste materials in production processes has therefore a great potential which is not related solely to binders but also to fillers. In this light, this paper aims at thorough investigations of concrete mixtures with crushed concrete pavements as partial or full replacement of natural coarse aggregates. The research combines experimental techniques to quantify the influence of the substitution on basic physical, mechanical, and heat/moisture transport/storage parameters. The experimental data obtained are further exploited as input data for computational prediction of coupled heat and moisture transport to assess the influence of the aggregates substitution on hygrothermal performance of the built-in concretes. In the last step, the environmental impacts are assessed. Since the changes in the hygrothermal performance were found to be insignificant (i), the compressive strength were improved by up to 25% (ii) and most of the environmental impact indicators were decreased (iii) at the same time, the findings of the research presented predeterminate such a reuse strategy to wider application and use.

Efficacy of Caffeine Treatment for Wood Protection-Influence of Wood and Fungi Species.

In the future, we can expect increased requirements to the health and ecological integrity of biocides used for the protection of wood against bio-attacks, and it is therefore necessary to search for and thoroughly test new active substances. Caffeine has been shown to have biocidal efficacy against wood-destroying fungi, moulds and insects. The aim of the research was to determine whether the effectiveness of caffeine, as a fungicide of natural origin, is affected by a different type of treated wood. Norway spruce mature wood (Picea abies), Scots pine sapwood (Pinus sylvestris), and European beech wood (Fagus sylvatica) were tested in this work. The samples were treated using long-term dipping technology or coating (according to EN 152:2012) and then tested against selected wood-destroying brown rot fungi according to the standard EN 839:2015, wood-staining fungi according to EN 152:2012, and against mould growth according to EN 15457:2015. The penetration of caffeine solution into wood depth was also evaluated using liquid extraction chromatography, as well as the effect of the treatment used on selected physical and mechanical properties of wood. The test results showed that the type of wood used and the specific type of wood-degrading agent had a significant effect on the effectiveness of caffeine protection. The most resistant wood was the treated spruce, whereas the most susceptible to deterioration was the treated white pine and beech wood. The results of the work showed that caffeine treatment is effective against wood-destroying fungi at a concentration of 2%, and at 1% in some of the tested cases. It can be used as an ecologically acceptable short-term protection alternative against wood-staining fungi in lumber warehouses and is also partially effective against moulds. It also does not have negative effects on changes in the physical and mechanical properties of the tested wood species.

Microstructure Formation of Cement Mortars Modified by Superabsorbent Polymers.

The utilization of superabsorbent polymers (SAPs) in cement-based materials has been found to be a promising means of mitigating the autogenous propagation of shrinkage and cracks. On the other hand, the undesired effects of SAPs' application on functional properties, including mechanical strength, microstructure formation, and the evolution of hydration heat are not properly understood, given the variety in SAPs' characteristics. To contribute to the present state-of-the-art, cement mortars, modified with two grades of SAPs by dosages of 0.3%, 0.6%, and 0.9%, were designed and studied with emphasis on the relationship between the materials' porosities and mechanical strengths. The obtained results are interpreted by scanning electron microscopy analysis and hydration heat evolution to elucidate the major changes and their driving factors. Besides the benefits associated with the mitigation of autogenous shrinkage, the achieved results point to an adverse effect of supplementation with SAP on mechanical strength at an early age, and an even more pronounced increase at a later age. The employed scanning electron microscopy images, together with mercury-intrusion porosimetry data, depict distortion in the material porosity as a result of the filling of formed voids and the closing of open ends by swelled hydrogels. Only the minor benefit of a greater cross-linking density was obtained by the formation of dense structures and the gains in mechanical strength therefrom.

Functional Properties of SAP-Based Humidity Control Plasters.

The application of materials with high moisture storage capacity close to the interior surface presents a prospective passive method for improving indoor relative humidity conditions. In this paper, lime-cement plasters containing three different types of superabsorbent polymers (SAPs) in varying dosages are introduced and their mechanical, hygric, and thermal characteristics are analyzed in a relation to microstructure. The experimental results show a significant effect of both SAP amount and chemical composition on all functional properties of studied plasters. The incorporation of 1.5% of SAP may induce up to 2.5 better moisture buffering, thus significantly improving the passive humidity control capability. Considering overall functional parameters of SAP-modified plasters, the dosage of 1 wt.% can thus be viewed as a rational compromise between the moisture storage capability and mechanical properties. The obtained wide sets of parameters can be utilized directly as input data of computational models suitable for the assessment of the interior microclimate of residential and administrative buildings.

Effect of Absorptivity of Superabsorbent Polymers on Design of Cement Mortars.

The functional properties of composites modified by superabsorbent polymers (SAPs) strongly depend on the swelling capacity of applied SAPs. In this sense, three types of commercially available SAPs namely Cablock CT, Hydropam, and Creasorb SIS with different chemical composition and particle size distribution were studied in this manuscript to reveal the differences in absorptivity as can be viewed as pretests for their utilization in concrete composites. In addition, absorptivity in distilled water, tap water, and 0.1 M NaCl solution are examined for determining the SAPs response for the change of the solution pH. To overcome problems with the teabag method inaccuracy, the new method is introduced. Besides to quantitative evaluation of the SAPs absorptivity, the correlation for the absorption and desorption period as the function of SAPs residence time within the examined solution is proposed. To access the effect of selected SAPs on functional properties, optimization based on the flow table test is employed and mechanical parameters are determined after 7, 14, 28, and 90 days of curing. Obtained results refer to substantial differences between particular SAPs and contribute to the understanding of the effect of SAP on the functional properties of cement-based materials.