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Soil correction and fertilization are important in the formation of pastures, but many producers neglect them or use ineffective alternatives. Slow-release fertilizers may harm the establishment of forage plants, as this is a crucial moment during the pasture formation stage. The objective was to evaluate establishment fertilization strategies on the morphogenic, structural characteristics and productivity of Xaraés grass (Urochloa brizantha cv. Xaraés). To this end, two experimental trials were conducted in a greenhouse, both under a completely randomized design. In the first, three establishment fertilization strategies were tested (strategy 1: without lime/NPK; strategy 2: lime + NPK; strategy 3: natural reactive phosphate), with six replications. In the second, a 3 × 10 factorial scheme was used, corresponding to the three establishment fertilization strategies and 10 evaluation dates (32, 39, 46, 53, 60, 67, 74, 81, 88, and 95 days) after emergence. of plants (DAE). In experiment 1 the morphogenic characteristics of the plant were evaluated, in the second the structure and dry mass production of the aerial part and roots of Xaraés grass were evaluated Higher (P

Following a comprehensive analysis of the stone degradation of the “Study Room”, in the Crow’s Cloister west wing (Convent of Christ, Tomar, Portugal), a multiapproach plan was made to address the salt problems encountered on its limestone columns. Chemical characterization studies were made to determine the concentration and the type of the efflorescence soluble salts involved, as well as the ionic composition of the limestone material of the column, and also, in which environmental conditions their harmful activity is reduced (or prevented). Finally, on site, the existing cement mortar was removed in a 30 cm area around the base of the column, and the ionic characterization obtained was submitted to the ECOS-RUNSALT software, which determined that simply by fixing the relative humidity at 65±2%, the weathering process would be substantially reduced – conditions different from the ones encountered.

Nondestructive testing techniques have attracted growing interest in the last few years due to their ability to assess material properties without damaging the specimens. The free-free resonance method is a nondestructive testing technique based on the analysis of the natural frequencies of a sample. This study presents and discusses the applicability of this technique, traditionally used on soils, for the mechanical characterization of rocks. With this aim, the free-free resonance method is used to obtain the dynamic elastic modulus and shear modulus of four carbonate rocks that have been widely used as construction materials in southern Spain. The results from the nondestructive evaluation of dry and saturated rocks, in combination with petrographic characterization and uniaxial compression tests, make it possible to assess the existing relationships between the mechanical properties of carbonate rocks and to evaluate the impact of porosity and moisture content on their mechanical behavior.

ABSTRACT: Strawberry guava (Psidium cattleyanumm Sabine) is a species native to southern Brazil which exhibits significant potential for economic exploitation. The objective of this study was to evaluate the growth response of strawberry guava subjected to liming and phosphate fertilizer in pre-planting. The treatments consisted of four lime levels: 0; 33.3; 66.6 and 100 % of the dose needed to increase the pH in water to 6.0, and four phosphorus (P) doses: 0; 83.3; 166.6 and 250 kg ha–1 of P2O5. Plant growth parameters were evaluated for three years. In the years 2018 and 2019, the mineral composition of leaves, photosynthethic pigment indices and mycorrhizal colonization on strawberry guava roots were measured. Liming and phosphate fertilizer altered neither plant growth nor the photosynthetic pigment indices and there was no interaction between the factors studied and the remaining variables evaluated. However, liming promoted increases in the Ca and Mg shoot content, and the phosphate fertilizer increased the levels of shoot P in the third year of growth. Mycorrhizal colonization was stronger when the P soil levels were low, which could explain the absence of response to phosphate fertilization on plant growth for the first three years after planting.

Abstract Tectonic stylolites are indicators of compressive deformation episodes in rocks and are commonly studied in terms of their geometrical attributes’ length (L), and maximum (D max ) and average (D avg ) amplitudes. These parameters were analyzed for vertical stylolites from a sinistral strike-slip fault zone in limestones from the Guia Formation, Paraguay Belt, and compared mathematically to scarce vertical stylolites away from the fault zone. The study aimed to understand the role of strain-induced stylolites on the thinning of faulted limestone layers. Stylolites range from 2.66 up to 28.15 mm in length and from 0.143 up to 1.378 mm in amplitude. The total contractional strain (ϵ) was calculated for 49 stylolites with maximum amplitude peaks of 0.762 mm, using the Kostrov formula. The strain produced layer thinning and growth of the stylolite population. Regions of high stylolite concentration accommodated 16.92% contractional strain, whereas strain values of 3.29% are present in portions with low stylolite density. Layer thinning is directly proportional to contractional strain (ϵ) values spatially induced by faulting. The stylolite morphology plays an essential role in the permeability structure at the reservoir scale, where it can act as a barrier or a channel for fluid flux.

One of the most common problems pavements have is the loss of adhesion and cohesion due to moisture damage. Tropical countries and rainy seasons are some of the causes for this type of distress on roads. Another factor that has high influence in this damage is the mineralogy of the aggregate. This research shows the results of adhesion and cohesion between the aggregates from a limestone quarry and two types of sandstones from different quarries, highly used for roads projects from Colombia, and the asphalt 60-70 (1/10) mm, same PG58-22. For determining the adhesion and cohesion, Bitumen Bond Strength tests were made for dry and wet conditions. In addition, the Surface Free Energy was measured for the aggregates and the asphalt. The results indicated that those type of aggregates are highly susceptible to moisture damage, due all values of humidity Index Damage (HDI) were less than 0,5. This indicates that it is necessary to use modifiers for controlling the stripping of the pavements due to Moisture Damage.

ABSTRACT Mato Grosso, with a total area of 903357 km², does not have an official methodology for estimating soil potential acidity (H + Al), and determination of H + Al using the standard method is onerous and time consuming. The objective of this study was to compare estimated values of H + Al determined using the standard calcium acetate method with those obtained using three buffer methods, namely, the Shoemaker, McLean, and Pratt (SMP) buffer, Sikora buffer, and Santa Maria buffer (SMB) methods, with samples of the main classes of cultivated soils in the state of Mato Grosso. A total of 196 soil samples were collected from the arable layer (0-20 cm) in agropastoral and adjacent native systems. Statistical models were obtained and compared with models used by laboratories that are hypothetically inadequate because there is no calibration for soils in the state. After laboratory analyses, the paired H + Al and equilibrium pH values corresponding to the equilibrium of each buffer solution (SMP buffer, SMB, and Sikora buffer) were subjected to nonlinear regression analysis (P < 0.05). The SMB method, which does not release pollutant residues into the environment, was better than the Sikora and SMP methods for replacing the standard method used in state laboratories for soil analysis, that is, H + Al (cm3 c dm-3) = 51.189 -25.70 ln(pHSMB) (R2 = 0.88, P < 0.0001). Thus, if laboratories use uncalibrated equations to estimate soil potential acidity, the recommended limestone correction will be underestimated or overestimated, which may compromise crop productivity in Mato Grosso.

Biodegradation of stones is a common and undesirable alteration in historical buildings. Restorers have been using different treatments, especially chemical methods, to prevent biodeterioration. These treatments often have disadvantages such as low long-term effectiveness, high toxicity on human health and the environment and/or physicochemical incompatibility with the original stone (chromatic alteration or chemical degradation). In this research, different biocidal treatments based on silver and titanium dioxide nanocomposites have been tested on limestones from Utrera’s quarry (Seville, Spain), a stone employed in historical buildings in the south of Spain. Two AgNPs syntheses have been studied; the principal difference between them was the use of trisodium citrate as stabilizer. Optimum nanocomposite composition and dosage to minimize chromatic alteration after application of treatments without cut down the biocide effectiveness have been set up. Treatments based on silver-titanium dioxide (Ag/TiO2) nanocomposites stabilized with citrate have been able to keep clean the limestone due to the biopatina formation reduction and the surface color change has been below 10%.

The paper’s field focuses on the Restoration of the Four Sewers Fountain of Daganzo and the improvement of its immediate environment, linked to the Plan of Fountains and Historical Gardens of the Regional Government of Madrid. Historically, this element has been a reference at a territorial level, being part of troughs net and cattle trails for livestock, besides urban scale, serving public utility and point of drinking water supplying for the village. The intervention has had a dual purpose. On the one hand, monument’s enhancement, recovering the original presence of the Fountain, altered after paving works of the square in 1985, which left it half-buried. On the other hand, recuperating the memory of the laundry, demolished on the same date, making it the main character of a new public space created around the pylon, which recovers its social role as meeting place for neighbors. This process has benefited from a deep archival previous research; documentation, conservation and display of archaeological remains discovered; and a thorough restoration work to return its values to this Cultural Heritage Property.

Shelters are commonly considered effective preventive conservation methods for excavated archaeological sites. However, archaeological remains covered with shelters are still deteriorating in many cases, and the shelters can even exacerbate the damage. Therefore, regular evaluations of the shelter behaviour are extremely important. This paper presents a summary of the main approaches to shelter performance assessment carried out to date. In addition, the application of geomorphological methods to heritage conservation has been reviewed. The objective is to determine their suitability for the evaluation of shelters. This paper also presents the main results from the study on the shelters at the Bishop´s Palace (Witney, England) and Hagar Qim (Malta) on limestone conservation using exposure trials. To conclude, recommendations based on the case-study sites have been made to improve the effectiveness of future approaches.

Building materials used at the Former Workers Hospital of Maudes, Madrid (Spain) were studied. The study addressed the information both achieved from documental resources and characterization techniques. Documentary work has enabled to know about the architect thought, the ideology of the project or the grounds that conditioned such materials selection; it also permitted to learn about materials provenance and/or its elaboration. Analytical studies provided information about petrographic features of the materials and their composition; limestone provenance was confirmed and new data on material manufacture were provided. Such information, which deserves to be known and disseminated, provides a significant heritage value to materials that shape cultural assets. Studies with a multidisciplinary approach represent a commitment to improve the knowledge and conservation of heritage.

The Gandharan archaeological sites are mostly located in the Indus Suture Zone and in the lower Swat. In a recent past, scholars observed the use of local different type of schists to build buildings and sacred artworks. In this new research we highlighted the use of limestone for stucco artefacts and architectural decorations. This limestone is not a local rock in Swat but its main, ex- tended and closer outcrops are located in the mountains northwest of Islamabad. Indeed, through specific analyses carried out by our team, the compatibility of these outcrops with the rocks used for stucco artefacts and stucco decorations of buildings was observed. This stucco was made by a mixture of different kinds of local crushed rocks (i.e. schists and granites).

Grisolia is one of the building stones most commonly found in the architectural heritage of southern Italy. Also known commercially as “gold stone” for its yellow intrusions, Grisolia was employed by the leading Calabrian schools of stonemasons, principally in the southern Italian regions of Calabria and Basilicata. It is an Upper Triassic crystalline carbonate quarried in the Verbicaro Unit on Calabria’s northern Tyrrhenian coast. Possessing petrographic, physical and mechanical properties that ensure stone strength and durability, it is a high-quality building material suitable for structural and ornamental uses. These properties can be attributed to its low open porosity and excellent hydric behavior (low capillary water absorption), as well as to its high mechanical strength and low anisotropy. These characteristics make it recommendable as a building material for both restoration and new construction.

Abstract: The objective of this work was to evaluate the effect of the use of steel slag as a soil acidity corrective and of mycorrhizal fungi associated with phosphate fertilization on corn plants. The study was performed in a greenhouse, using 3-kg pots with a Typic Haplorthox, in a 4x5x2 factorial arrangement, with four acidity correction treatments (C1, correction with dolomitic limestone at a dose of 4 Mg ha-1; C2, correction with steel slag at a dose of 4 Mg ha-1; C3, correction with a 1:1 mixture of 2 Mg ha-1 dolomitic limestone and 2 Mg ha-1 steel slag; and C4, control, without pH correction), five phosphorus doses (0, 42, 95, 213, and 480 mg dm-3), and the presence or absence of two arbuscular mycorrhizal fungi (Rhizophagus clarus and Gigaspora margarita), with five replicates. Steel slag was efficient in correcting soil pH and providing Ca and Mg for the plants; therefore, it could replace limestone. The inoculation with R. clarus and G. margarita, associated with P doses of 42, 95, and 213 mg dm-3, improved the development of corn plants after 45 days, resulting in greater plant height, stem diameter, leaf area, and shoot and root dry matter.

Water vapour permeability (WVP) is a key parameter for the sustainable thermal conditioning of buildings. The study of the WVP in concrete with supplementary cementitious materials (SCMs) allows for the design of structures with improved durability and sustainability. To our knowledge, there is insufficient experimental data in the literature regarding the WVP of concrete with SCMs. WVP tests were made on concrete mixes containing ground granulated blast-furnace slag (GGBFS) and limestone powder (LP) as a partial replacement for ordinary Portland cement, and of concrete mixes containing pozzolanic cement (NP). Results from three moisture gradients show that GGBFS induces the greatest reduction in WVP, followed by the NP. LP shows a diluting effect of the binder, which could be compensated by GGBFS in the ternary blend. From the comparison between the WVP and the capillary sorption rate, the influence of the SCMs on the connectivity of the smallest pores is assessed.

The aim of this study is the preparation of β-belite by a solid-state reaction using powdered limestone, amorphous silica and liquid alkali silicates. The raw materials were blended, the mixtures were agglomerated and then burnt. The resulting samples were characterized by X-ray diffraction analysis and scanning electron microscopy. Free lime content in the β-belite samples was also determined. The effects of CaO/SiO2 ratio (1.6–2.1), burning temperature (800–1400 °C), utilization of different raw materials (silica fume, synthetic silica, potassium silicate, sodium silicate, potassium hydroxide) and burning time (0.5–16 h) on free lime content and mineralogical composition were investigated. The purest ?-belite samples were prepared from a mixture of powdered limestone, silica fume and liquid potassium silicate with a ratio CaO/SiO2 = 2 by burning at temperatures between 1100 and 1300 °C for more than 2 h. Decreasing of the CaO/SiO2 ratio led to rankinite formation and lower a burning temperature led to the formation of wollastonite.

The Apodi Plateau, located in the northeastern part of the state of Ceará in Brazil, has limestone as its parent material, with significant variation in the soils formed in this region, as well as the presence of iron nodules, having been identified. The iron oxides have been used as indicators for evaluating the weathering processes of some soils, with the nodules being sources of information about pedogenic processes. Seeking to evaluate the influence of the karstic parent material and of the iron nodules on soil genesis in the Apodi Plateau, the morphological, physical and chemical properties of five profiles were evaluated, as well as of the iron nodules present in some horizons. The profiles were classified as RED-YELLOW ARGISOL Abruptic eutrophic plinthosol (P1), Tb HAPLIC CAMBISOL Eutrophic latosol (P2), RED-YELLOW ARGISOL Abruptic eutrophic plinthosol (P3), Tb HAPLIC CAMBISOL Eutrophic latosol (P4) and RED ARGISOL Eutrophic nitosol (P5). Changes in chemical, physical and morphological characteristics were observed at depth in some profiles, suggesting variation in the characteristics of the parent material. Nodules of class C1 (0.053 to 0.25 mm) and C2 (0.25 to 2.00 mm) were concentrated on the surface, alternating with a sub-surface concentration of class C3 (2.00 to 4.76 mm), C4 (4.76 to 7.90 mm) and C5 (7.90 to 19.1 mm). Profile P5, considered as more evolved, showed a predominance of classes C1, C2 and C3 in the surface horizons, indicating degradation of the larger-diameter nodules with the advancing weathering process.

Hot bituminous mixtures are becoming widely used in modern railway tracks in the sub-ballast layer. The reason is that these materials allow for both an increase in bearing capacity and greater protection of the substructure respect the traditional granular sub-ballast. Despite these advantages, the fact that these materials are manufactured at a temperature of 160°C means that their application can lead to an important increase in construction costs, pollution and energy consumption. This paper aims to study the possibility of using WMA manufactured at lower temperatures, as bituminous sub-ballast, in order to save energy and reduce emissions throughout the production process, as well as diminish the global costs of this layer. To this end, this study focuses on a comparison of the mechanical behaviour of warm and hot bituminous mixtures as sub-ballast under various loading conditions. The results indicate that WMA offers mechanical behaviour that is comparable to conventional HMA.

Rocks creep has a great importance in the evaluation of the long-term behaviour of elements built with or within these materials. In this work, a porous well-known limestone locally named as San Julián stone has been physically and mechanically characterized. Uniaxial compressive tests for 96 h. at constant stress are carried out. Long-term behaviour has been modelled by means of a well-known creep model, the CEB-FIP Model code 2010, used for modelling other stony-material (i.e. concrete). Furthermore, a rheological model has been proposed. The main aim of this work is to investigate the possibility of exploiting the vast experience accumulated in the study of concrete deformational long-term behaviour in order to obtaining a reasonable approach to the behaviour of the rock, for too long testing times difficult to implement in laboratory. A creep function adapted to the studied rock only dependent on its elastic and mechanical characteristics is also proposed in this work.

A produtividade agrícola nos trópicos é afetada, principalmente, pelos fatores ligados à acidez do solo (pH, saturação por bases, acidez potencial, disponibilidade de nutrientes). A calagem é uma prática bem conhecida para corrigir a acidez do solo em culturas anuais, ainda que não seja praticada com a regularidade necessária. Entretanto, em culturas perenes, a incorporação de corretivos é mais complexa, devido às características desse grupo de plantas e à carência de informações científicas sobre o assunto. Em condições de acidez, a calagem promove a neutralização do Al3+, a elevação do pH e o fornecimento de Ca e Mg, possibilitando a proliferação de raízes, com reflexos positivos no crescimento da parte aérea das plantas. Contudo, devido à baixa solubilidade e à lenta movimentação do calcário ao longo do perfil do solo, há obrigatoriedade de se fazer distribuição uniforme e incorporação profunda, antecedendo a implantação do pomar, a fim de garantir o eficiente aproveitamento de água e de nutrientes contidos nessas camadas. A calagem deve ser considerada um investimento, pois seus benefícios perduram além de um ano ou de uma safra agrícola. Isso se deve ao efeito residual dos corretivos de acidez do solo, sendo o tempo de duração desse efeito dependente de vários fatores, entre os quais: condições edafoclimáticas, cultura, manejo da área e tipo de corretivo empregado. Em geral, partículas maiores de calcário têm efeito residual mais prolongado, sendo empregadas na implantação dos pomares. No entanto, a relação entre o tamanho da partícula e o efeito residual tem sido pouco pesquisada, devido à necessidade de estudos de longa duração. Em função das elevadas doses de adubos nitrogenados utilizadas nos pomares de altos rendimentos, a acidez do solo aumenta, como resultado do processo de nitrificação. Em pomares já implantados, o procedimento atualmente utilizado pelos produtores é a incorporação superficial do calcário na área. As recomendações talvez fossem outras, caso houvesse maior subsídio da pesquisa, tendo em vista os diversos problemas fitossanitários que podem ocorrer, direta ou indiretamente da prática da incorporação do corretivo, tais como redução do sistema radicular, ferimento das raízes e consequente risco de infecções, com disseminação de pragas e doenças no pomar. O objetivo desta revisão é apresentar os principais resultados de pesquisas sobre o assunto, mostrando os efeitos da calagem sobre a fertilidade do solo, a nutrição e a produtividade de frutíferas de grande importância econômica para o Brasil, bem como discutir a duração do efeito residual dos corretivos e a dose mais ecônomica a ser aplicada nos pomares de frutas em implantação e em produção.Agricultural productivity in the tropics is affected first by soil acidity and related factors (pH, base saturation, potential acidity, nutrient availability). Liming is a well-known but irregularly used beneficial practice to correct soil acidity in annual cropping systems. For perennial crops such as fruit orchards, lime incorporation is more difficult to implement as a result of length of the rotation and lack of scientific support. The lime neutralizes exchangeable aluminum, increases pH and supplies Ca and Mg to the growing roots. Because lime moves slowly in the soil, it must be incorporated deeply and uniformly before establishing the orchard to enhance soil exploration by the root system. Compared to fertilizers and pesticides liming can impact soil properties during several consecutive seasons and its effect depends on soil type, contact with the soil as lime is incorporated, fruit species and liming material. In general, the effect of larger lime particles is long-lasting. In orchards, lime is applied before establishment using lime materials of varying grain sizes. However, the relationship between grain size and long-time effect has been little studied because long-time research is expensive. With increasing application of ammonium-based N fertilizers in high-yielding orchards, soil acidity increases as a result of nitrification. Farmers presently apply lime superficially to established orchards in absence of sufficient experimentation on possible damage to the root system, root infection, pest blooms and soil compaction. The aim of this chapter is to quantify the effect of liming experiments on soil fertility, mineral nutrition and yield of tropical orchards in Brazil during establishment and full production cycles and determine the economic lime rate optimum for a long-term effect.

A eficiência da aplicação superficial de corretivos pode ser melhorada por meio de compostos orgânicos, quantificados através dos cátions hidrossolúveis, liberados por resíduos vegetais. Porém, não se sabe se os teores desses compostos podem ser modificados pela aplicação de calcário e silicato. Objetivou-se com este trabalho avaliar o efeito da aplicação superficial de calcário e silicato no teor de cátions solúveis e condutividade elétrica do extrato da parte aérea das culturas de soja, milheto, aveia branca, braquiária, milho, feijão e guandu. O experimento foi conduzido entre 2006 e 2008 em um Latossolo Vermelho distroférrico em Botucatu-SP, em sistema de semeadura direta consolidado. O delineamento experimental foi em blocos casualizados, com dezesseis repetições. Os tratamentos foram 3,8 t ha-1 de calcário dolomítico, 4,1 t.ha-1 de silicato de cálcio e magnésio e uma testemunha, sem aplicação de corretivos no solo. Foram determinados os teores de cátions hidrossolúveis e a condutividade elétrica da parte aérea das culturas. Variações nos teores e na somatória de cátions hidrossolúveis não foram detectadas pela condutividade elétrica dos extratos vegetais da parte aérea das culturas. A aplicação dos corretivos elevou os teores de Ca2+ e Mg2+ solúveis nos extratos dos resíduos de soja, aveia e milheto; para o milho, houve elevação nos teores de Mg2+; além de aumento nos teores de Mn2+ nos resíduos do primeiro ano de braquiária, não havendo, entretanto, influência nos teores nas culturas de feijão, guandu e braquiária no segundo ano.The efficiency of the surface application of correctives can be improved by means of organic compounds, quantified by water-soluble cations released by plant residue. However, it is unclear whether the levels of these compounds can be modified by the application of limestone and silicate. The aim of this study was to evaluate the effect of the surface application of limestone and silicate on the levels of soluble cations and the electrical conductivity of the extract from the shoots of soybean, millet, oats, brachiaria, maize, beans and pigeon pea. The experiment was carried out between 2006 and 2008 in dystrophic red latosol in Botucatu SP, under a system of consolidated direct seeding. The experimental design was of randomized blocks, with sixteen replications. The treatments were 3.8 t ha-1 of dolomitic limestone, 4.1t ha-1 of calcium silicate and magnesium, and a control with no application of correctives to the soil. The levels of water-soluble cations, and the electrical conductivity of the crop shoots were determined. Variations in the levels and sum of water-soluble cations were not detected through the electrical conductivity of the shoot extract. The application of correctives increased the levels of soluble Ca2+ and Mg2+ in extracts from the residue of soybean, oats, and millet; for maize, there was an increase in the concentrations of Mg2+; in addition to increased levels of Mn2+ in the first-year brachiaria residue, with no influence however, on the levels in bean, pigeon pea and brachiaria crops in the second year.

Up to now, infrared thermographic approaches have been considered either passive or active. In the latter case, the heat flux is historically attributed to a non-natural heat source. The use of the sun has recently been incorporated into the active approach thanks to multi-temporal inspections. In this paper, an innovative hybrid thermographic (HIRT) approach is illustrated. It combines both the time component and the solar source to obtain quantitative information such as the defect depth. Thermograms were obtained by inspecting the facade of the Santa Maria Collemaggio church (L’Aquila, Italy), whereas quantitative results related to the sub-superficial discontinuities were obtained thanks to the use of advanced techniques. Experimental results linked to passive approach (i.e., the mosaicking procedure of the thermograms) performed by selecting a set of historic churches are also included in order to explain, when and where, the hybrid procedure should be used.

Objetivou-se, com este trabalho, avaliar o uso da alga Lithothamnium calcareum (Pallas) Areschoug nas rações para frangos de corte de 1 a 21 e 21 a 42 dias de idade, em substituição à fonte de cálcio tradicional (calcário calcítico). Para isso, foram utilizados 300 pintos machos, da linhagem Cobb®, que receberam rações contendo o calcário calcítico e a alga Lithothamnium calcareum (colhida de inteira e na forma de areia biodentrítica) como fontes de cálcio. O delineamento experimental utilizado foi o inteiramente casualizado, com três tratamentos e cinco repetições de 20 aves cada. As variáveis analisadas foram: ganho de peso (g/ave), consumo de ração (g/ave) e conversão alimentar (g/g). No final do experimento foram avaliados os parâmetros ósseos: peso da tíbia (g), comprimento da tíbia (mm), diâmetro da tíbia (mm) e teor de cinzas na tíbia (%). Na fase inicial (1 a 21 dias) houve efeito (PThe objective of this study was to evaluate the use of the algae Lithothamnium calcareum (Pallas) Areschoug in diets for broiler chickens from 1 to 21 and 21 to 42 days, to replace the traditional source of calcium (limestone). 300 male chicks from Cobb® strain, which received diets containing limestone and Lithothamnium calcareum algae (as a whole and as sand biodentritic) were used as sources of calcium. The experimental design was completely randomized, with three treatments and five replicates of 20 birds each. The variables analyzed were: weight gain (g / bird), feed intake (g / bird), feed per again (g / g). At the end of the experiment the bone parameters: weight of the tibia (g), tibia length (mm), diameter of the tibia (mm) and ash content in the tibia (%). Were evaluated in the initial phase (1 to 21 days) there was an effect (P

Application of calcium silicate (SiCa) as soil acidity corrective was evaluated in a Rhodic Hapludox soil with palisade grass conducted under pasture rotation system with different grazing intensities. Experimental design was complete randomized blocks with four grazing intensities - grazing intensities were imposed by forage supply (50, 100, 150 and 200 kg t-1 of DM per LW) - in experimental plots with four replicates and, in the subplots, with seven doses of calcium silicate combined with lime: 0+0, 2+0, 4+0, 6+0, 2+4, 4+2 and 0+6 t ha-1, respectively. In the soil, it was evaluated the effect of four levels of calcium silicate (0, 2, 4 and 6 t ha-1) at 45, 90, and 365 days at three depths (0-10, 10-20 and 20-40 cm) and at 365 days, it was included one level of lime (6 t ha-1). For determination of leaf chemical composition and silicate content in the soil, four levels of calcium silicate (0, 2, 4 and 6 t ha-1) were evaluated at 45 and 365 days and at 45 days only for leaf silicate, whereas for dry matter production, all corrective treatments applied were evaluated in evaluation seasons. Application of calcium silicate was positive for soil chemical traits related to acidity correction (pH(CaCl2), Ca, Mg, K, H+Al and V), but the limestone promoted better results at 365 days. Leaf mineral contents were not influenced by application of calcium silicate, but there was an increase on silicate contents in leaves and in the soil. Dry matter yield and chemical composition of palisade grass improved with the application of correctives.

Objetivou-se, com esta pesquisa, determinar a exigência de cálcio de codornas japonesas machos, no período de 1 a 21 dias de idade. Foram utilizadas 280 codornas com peso médio de 8 ± 2 g na fase inicial. As variáveis estudadas foram consumo de ração (CR), ganho de peso (GP) e conversão alimentar (CA). O delineamento experimental utilizado foi o inteiramente ao acaso, constituído de sete níveis de cálcio para cada fase, com quatro repetições de dez aves por unidade experimental. Os níveis de cálcio foram 0,85; 1,00; 1,15; 1,30; 1,45; 1,60 e 1,75%. As suplementações de cálcio foram realizadas através do calcário calcítico da ração. Verificou-se que o CR, o GP e a CA apresentaram efeito quadrático com o aumento dos níveis de cálcio na dieta. Recomenda-se dieta contendo 1,24% de cálcio para codornas japonesas machos no período de 1 a 21 dias de idade.The objective of this study was to determine calcium requirement of male japanese quails from 1 to 21 days of age. 280 quails with average weight of 8 ± 2 g in the initial phase were used. The evaluated performance parameters were feed intake (CR), weight gain (GP) and feed conversion (CA). A completely randomized experimental design was used, with seven calcium levels and four replicates of ten birds per experimental unit. Calcium levels were 0.85, 1.00, 1.15, 1.30, 1.45, 1.60 and 1.75%. Limestone was added to the diet as calcium supplementation source. It was found that CR, GP and CA showed a quadratic effect with the increased levels of calcium in the diet. It is recommended diet containing 1.24% calcium for male japanese quail in the period from 1 to 21 days of age.

O presente trabalho objetivou avaliar a calagem e adubação orgânica na produção de biomassa e óleo essencial em Lippia citriodora Kunth. O delineamento experimental utilizado constou de fatorial 7 x 2, sendo sete tratamentos (testemunha; adição de sulfato de Ca e Mg; calcário dolomítico; silicato de Ca e Mg; sulfato de Ca e Mg + esterco de curral; calcário dolomítico + esterco de curral; silicato de Ca e Mg + esterco de curral) e duas épocas de colheita, com quatro repetições, inteiramente casualizado (DIC). Verificou-se que a correção do solo mostrou-se prática necessária para o desenvolvimento da Lippia citriodora. Independentemente da época de colheita, a produção de massa fresca e seca foi maior com a aplicação do esterco de curral (32 t ha-1), no entanto, isso não refletiu em maior rendimento de óleo essencial.The present work aimed to evaluate the effect of liming and bovine fertilization on Lippia citriodora Kunth phytomass and essential oil production. The experimental design was completely randomized with seven treatments (control; Ca and Mg sulfate; limestone; Ca and Mg silicate; Ca and Mg sulfate + manure; limestone + manure; Ca and Mg silicate + manure) and two harvest seasons, with four replicates. Soil adjustment showed to be a necessary procedure for Lippia citriodora development. Independently of the harvest season, fresh and dry matter yields were higher under treatments with bovine manure (32 t ha-1); however, no effect of treatments was observed on essential oil concentration.

The Abanto natural stone is a rock used in modern constructions and currently quarried as an ornamental rock in Abanto, Zaragoza. The varieties described here are a limestone with depositional texture and a crystalline limestone. In this work we have carried out a detailed study of the mineralogy, texture, hydric behaviour, pore system characteristics, dynamic behaviour and behaviour against the effects of salt crystallisation. After 30 cycles of salts crystallization, the weight loss in these rocks is lower than 0.5%. This low weathering is a consequence of the configuration of their pore system, characterised by a low open porosity and high percentages of microporosity with pore-throat sizes on average of less than a 0.2 µm. The petrographical and physical characteristics, as well as its high resistance against salt crystallisation confer these rocks a high technical quality for their use as building stones in modern construction.

Com o objetivo de estudar a relação entre doses de calcário e produção de goiabas, um ensaio de campo foi conduzido em solo Latossolo Vermelho distrófico, no município de Bebedouro-SP, no período de 1999 a 2006. O delineamento experimental adotado foi em blocos casualizados com cinco tratamentos e quatro repetições. O calcário foi aplicado uma única vez em 1999, nas doses de: zero; 1,85; 3,71; 5,56 e 7,41 t ha-1. A produção das goiabeiras aumentou em resposta à aplicação do corretivo de acidez. As produções acumuladas de frutos, nos anos sucessivos 2003, 2004, 2005 e 2006 estiveram associadas às doses mais econômicas de calcário de 1,6; 4,4; 7,2 e 7,2 t ha-1, respectivamente.With the objective of studying the relationship between limestone doses and guava production, a field experiment was conducted on Oxisol soil in the town of Bebedouro-SP, from 1999 to 2006. The experimental design was randomized blocks with four replications. The limestone was used only once in 1999, at doses from zero, 1.85; 3.71; 5.56 and 7.41 t ha-1. The guava production increased in response to the application of the acidity corrective. The accumulated production of fruits in successive years 2003, 2004, 2005 and 2006 were associated with economical doses of limestone of 1.6; 4.4; 7.2 and 7.2 t ha-1 respectively.

The purpose of this research is to analyse an alleged rock-art engraving found at Pedrógão Beach (Leiria, Portugal), by studying its geological and geomorphological context, the weathering processes of the outcrop, of the rock fragments located south of the beach, as well as the same stone slab where the assumed rock-art engraving was identified. The stone slab was found in a small cave (named Gruta da Pedra) opening in limestone south of Pedrógão beach. The study provides new data on the evolution of the site in the Quaternary and clarifies some doubts on the authenticity of the "rock-engraving", by showing that it is actually a natural object, with no evidence of human intervention.

The present paper aims to interpret the SO2 diffusion mechanism process for two different limestones: a calcite and a dolomite. In previous study, the apparent activation energies for sulfation reaction were between 3.03 and 4.45 kJ mol-1 for the calcite, and 11.24 kJ mol-1 for the dolomite. Using nitrogen porosimetry it was possible to observe that the dolomite presents mesopores of 0.03 μm, while the calcite presents mesopores of 0.01 μm. The evaluation of limestones porous structure together with their kinetic parameters, allowed concluding that the diffusion mechanism follows Fick law and Knudsen law for dolomite and calcite, respectively.

The aim of this work is to propose a methodology to evaluate the evolution of the pore blockage of limestone during the sulfation reaction. The experiments were performed for a national limestone (dolomite) with average particle size of 545 μm in interrupted sulfation tests were conducted at seven different times and at three different temperatures of the process. The empirical data were obtained from porosimetry tests to establish BET surface area, volume and average size of pore and distribution of pore sizes of the sulfated samples. Thermogravimetric tests were performed to evaluate the preparation methodology of the samples used in the porosimetry tests.

Objetivou-se com este trabalho avaliar a susceptibilidade à deterioração aeróbia e às perdas de matéria seca da cana-de-açúcar in natura ou ensilada com ou sem aditivos químicos, bem como de rações formuladas com esses volumosos. O experimento foi desenvolvido em delineamento inteiramente casualizado, com quatro repetições, composto da cana-de-açúcar in natura ou ensilada com cal virgem ou calcário no nível de 1% da massa verde. Avaliou-se a estabilidade aeróbia dos volumosos e das rações, por meio do monitoramento da temperatura, do pH e das perdas de matéria seca, durante dez dias. O tratamento da cana-de-açúcar com cal virgem melhorou a estabilidade aeróbia, evidenciada pelo maior tempo para elevação de temperatura e pelas menores perdas de matéria seca. A cana-de-açúcar in natura mostrou-se mais propensa à deterioração, com maior aumento da temperatura e maior perda de matéria seca. Nas rações contendo os volumosos, também foi observada superioridade das silagens tratadas com aditivos químicos, bem como melhoria na estabilidade aeróbia, em comparação aos volumosos sem os componentes das rações. Os aditivos foram efetivos na melhoria da estabilidade das silagens e na redução das perdas de matéria seca. A cana-de-açúcar in natura apresentou maior susceptibilidade à deterioração aeróbia em comparação às silagens. As rações contendo os volumosos tornaram a deterioração aeróbia mais tardia, revelando-se como possível estratégia para melhoria do manejo dentro da propriedade.The objective of this experiment was to evaluate the susceptibility to aerobic deterioration and dry matter losses of fresh sugarcane and silages with or without chemical additives, and diets composed formulated with these bulks. The experiments were conducted in a complete randomized design with four replications, consisting of fresh or ensilaged sugarcane with calcium oxide or limestone at the level of 1% fresh matter. The aerobic stability was assessed of the bulks and diets by monitoring temperature, pH and dry matter losses during ten days. The treatment sugarcane with calcium oxide improved aerobic stability, shown by the longer time needed to raise the temperature and the smaller dry matter losses. Fresh sugarcane was more susceptible to deterioration, showing the highest temperature increase and dry matter losses. Diets containing bulk also showed the superiority of the silage treated with chemical additives and improvement in aerobic stability, compared to bulks without the diet components. The additives were shown to be effective in improving silage stability and reducing dry matter losses. Fresh sugarcane was more susceptible to aerobic deterioration than silages. Diets containing sugarcane silage with additives delayed the aerobic deterioration and may be a possible strategy to improve farm nutritional management.

Objetivou-se com este estudo avaliar os efeitos de aditivos químicos na ensilagem de cana-de-açúcar sobre a dinâmica fermentativa e a composição química das silagens. O experimento foi desenvolvido em delineamento inteiramente casualizado, com cinco repetições. A cana-de-açúcar foi ensilada sem aditivo ou tratada com 1% (massa verde) de cal virgem ou calcário, constituindo três tratamentos. A dinâmica fermentativa foi analisada com base nas perdas gasosas, nos ácidos orgânicos, na produção de etanol e na composição química das silagens. As menores perdas gasosas foram observadas nas silagens com cal virgem ou calcário. As silagens tratadas com esses aditivos apresentaram maior teor de carboidratos solúveis residuais e de ácidos acético e butírico, além de reduzida fermentação alcoólica. As silagens com os aditivos químicos apresentaram, no momento da abertura, maior teor de cinzas e menor concentração de componentes fibrosos. O teor de proteína observado nas silagens está de acordo com a amplitude preconizada para a forragem in natura. A adição de cal virgem ou calcário no momento da ensilagem melhorou o padrão fermentativo das silagens, promovendo redução das perdas gasosas, inibição da fermentação alcoólica e maior quantidade de carboidratos solúveis remanescentes.The objective of this study was to evaluate the effects of chemical additives on the fermentative dynamics and chemical composition of sugarcane silages. The experiment was conducted in a randomized complete design with five replications. Sugarcane was ensiled without additives or with calcium oxide and limestone (1% as-fed basis) constituing three treatments. The fermentative dynamic was analyzed based on gas losses, organic acids and ethanol production and, silages chemical composition. The calcium oxide and limestone treatments showed the lowest values of gas losses. Silages treated with these two additives also showed higher concentrations of water soluble carbohydrates, acetic and butyric acids, and low alcoholic fermentation. The treatments containing chemical additives presented the highest ash and the lowest fiber concentration. Crude protein for all treatments was in agreement with the values of fresh sugarcane. Calcium oxide or limestone addition at ensiling resulted in a better fermentative pattern, promoting reduction in gas losses, alcoholic fermentation inhibition, and high amounts of residual soluble carbohydrates.

This study consisted in characterizing the materials used to build Santa Marina de Aguas Santas Church at Cordoba and locating the original quarries. The techniques used in the lithological and chemical characterization included XRD, petrographic microscopy and electron dispersive scanning microscopy. The chemical index of weathering (CIW) was used to quantify the state of stone decay. The lithology and different types of alterations observed were mapped. A comparison of the material on the building to ancient quarries identified “Naranjo” as the possible site where the stone was originally quarried.

A correção da acidez superficial e subsuperficial do solo, em especial para culturas perenes, é fundamental para garantir o rápido estabelecimento do pomar e a precocidade da produção de frutos. O presente trabalho objetivou avaliar os efeitos da calagem na implantação e formação de um pomar de caramboleiras (Averrhoa carambola) e seus reflexos no solo, na planta, na produção de frutos, bem como determinar a duração do efeito residual da aplicação inicial do calcário. O experimento foi realizado na Estação Experimental de Citricultura de Bebedouro, São Paulo, em um Latossolo Vermelho distrófico (V inicial = 26% na camada de 0-20cm), no período de agosto/1999 a julho/2006. As doses de calcário empregadas foram: 0; 1,85; 3,71; 5,56 e 7,41 t ha-1. Durante 78 meses após a aplicação do corretivo, foram realizadas análises químicas de solo, bem como a avaliação do estado nutricional e da produção de frutos durante cinco safras agrícolas. A calagem proporcionou melhoria das características químicas do solo, elevando o pH, Ca, Mg, V% e diminuindo o H+Al, até 60 cm de profundidade. Os teores foliares de Ca e Mg aumentaram, correlacionando-se positivamente com a produção de frutos. A maior produção acumulada de carambolas esteve associada à saturação por bases de 40 e 53% na linha e na entrelinha do pomar de caramboleiras, respectivamente.The correction of the superficial and subsurface acidity of the soil, especially for perennial crops, is essential to ensure the fast establishment of the orchard and the early production of fruits. The present work aimed to evaluate the effects of liming in the implantation and formation of a star fruit orchard (Averrhoa carambola) and its reflections in the soil, the plant, the fruit production, as well as determining the duration of the residual effect of the initial application of the calcareous rock. The experiment was conducted at the Citrus Experimental Station in Bebedouro, São Paulo, in a Typic Haplustox (V initial = 26% in the 0 to 20 cm layer) between August 1999 and July 2006. The doses of limestone were: 0, 1.85, 3.71, 5.56 and 7.41 t ha-1. During 78 months after the implementation of the corrective soil chemical analyses were performed as well as the evaluation of the nutritional status and the fruit production during five agricultural harvests. The liming provided the improvement of the chemical characteristics of the soil, raising pH, Ca, Mg, V% and reducing the H+Al, down to 60 cm deep. The leaf levels of Ca and Mg increased, correlating itself positively with the fruit yield. The highest combined star fruit production was associated with base saturation of 40 and 53% in the line and between the line of the star fruit orchard, respectively.

Este estudo foi realizado com o objetivo de avaliar o fosfato monoamônio (MAP) como fonte de fósforo e o calcário calcítico Paraíso (CP) com mais alto nível de magnésio (1,92%) como fonte de cálcio para poedeiras comerciais. Foram alojadas em gaiolas 280 poedeiras brancas Dekalb durante o período de 46 a 58 semanas de idade. O delineamento experimental foi o inteiramente casualizado com quatro tratamentos (fontes de cálcio e fósforo), sete repetições e dez aves por unidade experimental. As fontes de cálcio e fósforo avaliadas foram: FBC/CB - fosfato bicálcico e calcário calcítico Barroso (cinza); FBC/CP - fosfato bicálcico e calcário calcítico Paraíso (branco); MAP/CB -fosfato monoamônio e calcário calcítico Barroso; MAP/CP - fosfato monoamônio e calcário calcítico Paraíso. Foram avaliados a produção, o peso médio e a massa dos ovos, o consumo de ração, a conversão alimentar e o percentual e a espessura da casca. A produção, o peso médio e a massa de ovos melhoraram com a utilização de fosfato monoamônio e ambas as fontes de calcário avaliadas. O consumo de ração aumentou e a conversão alimentar melhorou com a utilização de MAP como fonte de fósforo. O percentual e a espessura de casca dos ovos não foram significativamente influenciados pela fonte de cálcio da dieta, logo, o nível maior de magnésio e a menor granulometria do calcário Paraíso não comprometeram a qualidade da casca dos ovos. Não foram observadas alterações na consistência das fezes e na taxa de mortalidade das poedeiras em produção. A excreção de nitrogênio foi 10% maior nas aves que consumiram o fosfato monoamônio como fonte de fósforo. O fosfato monoamônio pode ser utilizado como fonte alternativa de fósforo em substituição ao fosfato bicálcico. A utilização de calcário Paraíso é tecnicamente viável na alimentação de poedeiras comerciais e não prejudica a produção e a qualidade da casca dos ovos.The objective of this study was to evaluate the monoammonium phosphate (MAP) as a source of phosphorus and Paraíso limestone (CP) with higher magnesium levels (1.92%) as a source of calcium for commercial layers. A total of 280 white Dekalb chickens were housed in individual cages during the period from 46 to 58 weeks old. A completely randomized experimental design, with four diets, seven replicates and ten birds per experimental unit were used. The diets were: FBC/CB - dicalcium phosphate and Barroso limestone (gray); FBC/CP - dicalcium phosphate and Paraíso limestone (white); MAP/CB - monoammonium phosphate and Barroso limestone; MAP/CP - monoammonium phosphate and Paraíso limestone. Egg production, mean weight and egg mass; feed intake and feed conversion were evaluate, and also shell percentage and thickness. Egg production, mean egg weight and mass improved with the use MAP with both evaluated limestone. Feed intake and feed conversion improved with utilization of MAP as source of phosphorus. Egg shell percentage and thickness were not affected by calcium source in the diet, hence, the higher level of Mg and finer particles of Paraíso limestone did not impaired egg shell quality. No alterations were observed in feces consistency and survival rate of the layers. The nitrogen excretion was 10% higher for birds that received MAP as a phosphorus source. Monoammonium phosphate could be used as an alternative source of phosphorus replacing dicalcium phosphate; and Paraíso limestone is technically viable for feeding commercial layers without problems for egg production and shell quality.

The water- and dirt-repellent properties of fluorinated products have been used primarily in waterproof coatings. The development of new materials or the definition of new functions for existing substances may extend the possible application of these systems to other specific uses, such as new anti-graffiti coatings to guarantee easy clean-up in the event of this kind of vandalism. The present study aimed to assess the anti-graffiti protection afforded by a fluoralkyl siloxane in limestone and granite. The results show that the surface of the substrates darkened and yellowed slightly under the treatment and that the total colour variations (ΔE*) found after the first cleaning were similar in the two substrates. After subsequent graffiti painting-cleaning cycles, ΔE* was greater in the granite, due to its more rugged surface. Water absorption declined, particularly in the low porosity granite, after it was coated. Water repellence was likewise more effective in the granite, whose low initial permeability decreased, but less steeply than in the limestone. The graffiti lowered the water repellence of the treated surfaces. Although the waterproof protection afforded by the coating was not fully recovered after cleaning, the treated specimens were still more water repellent than the uncoated stone. The siloxane polymer penetrated the limestone to a depth of several tenths of a micron, but remained on the surface in the granite.

Magnesium sulfate salts often result from the combination of incompatible construction materials, such as stone or mortar with high magnesium content and sulfates from adjacent mortars or polluted air. When combined with a source of moisture, these materials react to form soluble salts, often leading to significant damage by flaking of the stone, as the magnesium sulfate responds to fluctuating environmental conditions. Several laboratory experiments were performed to reproduce surface flaking on different types of limestone from Spain and the UK to evaluate the effects of humidity cycling on the damage of stone by salt crystallization. The two salt solutions used for the experiments were a single salt of magnesium sulfate and a mixture of magnesium sulfate, calcium sulfate and sodium chloride, a typical salt mixture found in damaged stone at the site of Howden Minster (UK). A climate chamber with precise and programmable temperature and humidity control was used to test the hypothesis that salt damage in the stone can be readily caused by humidity fluctuations. Damage was monitored using Linear Variable Differential Transformer (LVDT), which measure transducers displacement by dimensional change on the order of microns. In addition, Ion Chromatography, Environmental Scanning Electron Microscopy with energy dispersive X-ray spectroscopy (ESEM-EDX) and X-ray Diffraction analyses (XRD) were also carried out to analyze salt behavior. Damage by flaking took place in two types of magnesian limestone cubes impregnated with the salt mixture, from Cadeby quarry and York Minster, apparently by deliquescent salts of low equilibrium relative humidity (RHeq), while the rest of the samples developed a salt crust over the surface, but no damage was observed in the stone. It is important to verify hypotheses developed from field observations with laboratory experiments. By combining both field and laboratory data, a clearer understanding the different mechanisms of decay and associated weathering types under different environmental conditions can be obtained.

“Sierra Elvira stone” is one of the ornamental building stones most widely used in the historical monuments of eastern Andalusia. A Liassic age limestone, it appears in the central section of the Baetic Mountains and more specifically in the Middle Subbaetic domain. While the most common variety is a crinoid limestone, a micritic limestone of the same age has also been quarried, albeit in much smaller quantities. These stones form very thick beds, up to nearly 5 m deep, that run in consistently parallel lines and have a dip angle that facilitates quarrying. With petrographic, physical and mechanical properties that ensure stone strength and durability, it is a high quality building material suitable for both structural and ornamental purposes. These properties can be attributed to the minimal open porosity and concomitant excellent water resistance that characterize the stone, as well as to its high mechanical strength and low textural anisotropy, both elastic and mechanical. With such attributes, the stone can be successfully used for any number of purposes, including decorative stonework (portals, fountains, plinths), structural members (column shafts and bases) or urban curbing and paving. Intervention on Sierra de Elvira limestone structures should be limited to cleaning or repair, for consolidating or protective materials are scantly effective.

Two types of ornamental stones, namely granite (Blanco Rafaela or Zarzalejo Granite) and microcrystalline limestone (marble known commercially as Gris Pulpis), treated for different surface finishes, were tested for suitability as paving slabs. The finishes tested in both stones were polishing, hammering, honing and flaming, while acid treatment and abrasion were applied to limestone only and sawn finishes were only studied in granite. The stones were tested for the three physical properties that determine suitability for use as paving slabs; flexural strength under a concentrated load, and abrasion and slip resistance. Laboratory freeze-thaw cycle ageing tests were also conducted and flexural strength subsequently evaluated. Stone water sorption proved to be substantially unaltered by the type of finish employed. Finish barely affected flexural strength, except in the case of limestone flaming, where it was lower. Hammering was found to provide good slip resistance in both stones. The best slip performance for granite, however, was found for flamed specimens. Finish was shown to have no effect on abrasion resistance in either of the stone materials. Polished limestone suffered the least damage in freeze-thaw cycles, whereas freeze-thaw resistance was similar in all the granite specimens, regardless of the finish used.

Fue realizado un estudio sobre el efecto de las concentraciones de SO2 en la absorción por calcáreo en hornos de Lecho Fluidizado. Para observar la influencia del SO2 en los parámetros de diferentes procesos físicos y químicos fueron creados ambientes para cuatro concentraciones diferentes de SO2 : 500, 1000, 2000 y 4000 ppm. Se utilizaron dos tipos de calcáreos: Dolimitico-DP y el Calcítico-CI. El Lecho Fluidizado Burbujeante utilizado tiene 160 mm de diámetro interno y fue fluidizado con aire a la temperatura de 850 °C, con una concentración de SO2 deseada. Como material del lecho fue utilizada la arena de cuarzo (99,9%) con diámetro de 385 µm y de masa aproximadamente 3,0 kg. El calcáreo fue adicionado en dosificación de 50 g con el reactor ya pre-calentado. Las variaciones de las concentraciones de SO2, CO2, CO, O2 y las descargas, fueron monitoreadas continuamente a la salida del ciclón que fue utilizado para la retención de la partícula fina. Para esos dados se desarrolló un programa en LabView. El modelo matemático escogido posibilitó la determinación de la conversión.A study of the effect of the concentrations of SO2 in its absorption by limestones in fluidized bed furnaces was conducted. For the determination of the SO2 influence on the different physical and chemical parameters of process, such as calcinations and sulfatation four different atmospheres were used in the reator with concentrations of SO2 of 500, 1000, 2000 and 4000 ppm. Two types of limestones were used: Dolomite-DP and Calcitic-CI. The bench scale bubbling fluidized bed reactor had a 160 mm internal diameter and was fluidized with air at 850 °C containing the required concentration of SO2. Bed material was quartz sand (99,9%) , with 385 µm diameter and approximately 3 kg of mass. The limestone was introduced in samples of 50 kg in the reactor previously stabilized and their discharges in the reactor exit were continually monitored. For the recording of this parameters a data acquisition program in LabView was developed. A mathematical model was used to allow the determination of the conversion, the conversion rate and the global coefficient of reaction rate for all the test conditions.

Sulfur emission in coal power generation is a matter of great environmental concern and limestone sorbents are widely used for reducing such emissions. Thermogravimetry was applied to determine the effects of the type of limestone (calcite and dolomite), particle size (530 and 650 µm) and atmosphere (air and nitrogen) on the kinetics of SO2 sorption by limestone. Isothermal experiments were performed for different temperatures (650 to 950 ºC), at local atmospheric pressure. The apparent activation energies, as indicated by the slope of the Arrhenius plot, resulted between 3.03 and 4.45 kJ mol-1 for the calcite, and 11.24 kJ mol-1 for the dolomite.

With today’s extensive use of cements containing two or more additions (blended cements), predicting concrete durability on the grounds of its strength alone leads to errors that may affect the service life of the resulting structures. Indeed, concrete of a given strength class can be made from different materials and proportions of widely varying durability. The present study evaluated water absorption, sorptivity and initial surface absorption in concrete made with unadditioned Portland, binary (limestone) and ternary (limestone and granulated slag) blend cement.

The Devonian micritic limestones from the Prague Basin (Barrandian area, Bohemian Massif, Czech Republic), which were the primary raw material used for natural hydraulic lime burned in Prague, exhibit a feebly to eminently hydraulic character. Based on a laboratory experimental study, the burned product is composed of dominant free-lime (CaO) and/or portlandite (Ca(OH)2), larnite-belite (bicalcium silicate 2CaO.SiO2), and quartz (SiO2) - i.e. phases formed due to the decomposition of carbonate and quartz, present in the original limestones. Proportions of the newly formed phases depend on: the composition of the raw material, maximum burning temperature (the highest amount of larnite-belite appearing at a burning temperature of 1200 °C), and the granulometry of the experimental batches (a coarsely-ground batch exhibited a higher amount of larnite-belite compared to the finely-ground one). The presence of minor phyllosilicates in the raw material contributed to the formation of gehlenite, brownmillerite, wollastonite, calcium aluminate, and/or spurrite.

Limestone is one of the most frequent building stones used in monuments in Egypt from ancient Egyptian times and salt weathering is one of the main threats to these monuments. During this work, cylindrical limestone samples (2 cm diameter and approx. 4 cm length) from Mokattam group, one of the most frequent materials in historic Cairo, were subjected, in a purpose-made simulation chamber, to laboratory salt weathering tests with a 10% weight NaCl solution at different temperatures (20, 30, 40 °C). During each test, temperature was kept constant and salt solutions flowed continuously imbibing samples by capillary rise resembling the way they get into building stone in many real cases. Air temperature, relative humidity inside the simulation chamber and also samples weight were digitally monitored and recorded. Results show the influence of temperature and the ratio between imbibitions and evaporation on the dynamics of salt crystallization in the samples.

While there is ample information in the literature on the mechanical performance and durability of concrete made with either limestone or granulated blast furnace slag,very little is known about the effect of the combined action of these two additions on concrete properties. The present paper evaluates the early stage properties and mechanical strength of binary and ternary cement concrete containing up to 18% limestone and 20% granulated blast furnace slag. The results show that the use of ternary cements has no substantial effect on concrete setting time, although it does reduce bleeding and enhance mechanical strength with respect to unadditioned Portland and/or binary cement concrete.