Lime Wash Research Articles

Minerva in Colours: First Results on a Polychrome Roman Sculpture from Carnuntum (Pannonia)

This paper presents the first results of a current interdisciplinary research project on the polychromy of Roman provincial stone artefacts in selected areas of the Danubian provinces (PolychroMon). The statuary group of Minerva and the Genius immunium from Carnuntum (Archaeological Museum Carnuntinum inv. CAR-S-48) is dated to the second half of the second century AD and still retains traces of the original polychromy. The aim was to focus on non-invasive techniques and to employ micro-invasive methods for necessary cross-checking and gaining information otherwise not accessible. The investigation revealed that paint was applied on a layer of white lime wash. Additionally, the object shows several traces of Egyptian blue, which was mainly detected in Minerva’s and the Genius’ clothes. Other pigments whose traces were found on the sculpture include green earth, yellow and red ochre, as well as red lead and carbon black. Microscopic analysis confirms the presence of modern-age compounds as well (barium sulphate and zinc oxide) used for modern retouches. Gas chromatography–mass spectrometry revealed the use of egg as the major proteinaceous binding medium in the red lead polychromy.

Evaluation of Passive Cooling and Thermal Comfort in Historical Residential Buildings in Zanzibar

Indoor thermal comfort is essential for occupants’ well-being, productivity, and efficiency. Global climate change is leading to extremely high temperatures and more intense solar radiation, especially in hot, humid areas. Passive cooling is considered to be one of the environmental design strategies by which to create indoor thermal comfort conditions and minimize buildings’ energy consumption. However, little evidence has been found regarding the effect of passive cooling on the thermal comfort of historical buildings in hot–dry or hot–humid areas. Therefore, we explored the passive cooling features (north-south orientation, natural ventilation, window shading, and light color painted walls) applied in historic residential buildings in Zanzibar and evaluated the residents’ thermal responses and comfort perception based on questionnaires and field surveys. The results showed that the average predicted mean votes (PMVs) were 1.23 and 0.85 for the two historical case study buildings; the average predicted percentages of dissatisfaction (PPD) were 37.35% and 20.56%, respectively. These results indicate that the thermal conditions were not within the acceptable range of ASHRAE Standard 55. Further techniques, such as the use of lime plaster, wash lime, and appropriate organization, are suggested for the improvement of indoor thermal comfort in historical buildings in Zanzibar. This study provides guidelines to assist architects in designing energy-efficient residential buildings, taking into account cultural heritage and thermal comfort in buildings.

Performance of lime-metakaolin pastes using gravel wash mud (GWM)

The performance of ternary binders using lime, metakaolin (MK) and gravel wash mud (GWM) powders is studied for the development of novel lime-pozzolan pastes. This study examines the influence of varying mixture proportions using different types and compositions of lime powders and GWM at different treatment levels on the mechanical properties of lime-MK-GWM pastes. Various characterisation techniques including particle size distribution (PSD), X-ray fluorescence (XRF), X-ray diffraction (XRD), compressive strength tests, simultaneous thermal analysis (STA) and scanning electron microscopy (SEM), were applied on the different raw materials, respectively, on the hardened pastes to determine the reaction kinetics, the resulting microstructure and the mechanical performances of the lime-MK-GWM binder systems. Higher strength-enhancing contributions of thermally treated GWM powders (calcined at 850 °C) leading to compressive strengths up to 18 MPa were confirmed and the strength-based evaluations revealed that hydrated lime-based pastes achieved higher mechanical performances than hydraulic lime-based binder systems.

The influence of pre-wetting with consolidants on the adhesion of double-layer lime based mortars

Multilayer mortar systems have been diachronically used in historic structures. Renders and plasters were usually based on lime and presented specific characteristics (i.e. stratigraphy), while their durability was mostly attributed to the adhesion and overall performance of the mortar layers. During restoration works, the replacement or repair of successive mortar layers (i.e. renders, plasters, mural paintings’ substrates) is a common practice, whose effectiveness is closely related to the proper materials and techniques applied. In this paper, an effort was made to enhance the properties of a double-layered mortar system, based on lime and natural pozzolan. To this direction, pre-wetting of the internal layer was performed, using various organic and inorganic water-solutions (lime wash, primal, hydroground) that were further nano-modified (1.5% w/w, nano-silica). A series of specimens were manufactured and their physico-mechanical properties were tested at the age of 28 and 90 days (porosity, apparent specific gravity, water absorption coefficient, vapor permeability, dynamic modulus of elasticity, flexural and compressive strength). Additionally, bond strength by pull off and tensile bond strength were performed. From the evaluation of the results, it was concluded that the application of the proposed nano-modified solutions improved significantly the adhesion of the mortar layers. The results were encouraging, indicating that a limited, low cost and non invasive technique, could enhance their performance, during restoration works.

Mango value chain improvement through postharvest research and development: a developing country case study

Pakistan is one of the major mango-producing and -exporting countries in the world. During 2007-15, significant postharvest research and development (R&D) work was conducted under the Australian-funded ASLP mango supply chain management/value chain improvement projects (two phases). The project started by laying a postharvest foundation R&D infrastructure in 2007. Fruit quality losses in supply chains were documented. Protocols were developed for maturity testing, de-sapping, storage/sea-freighting, and ripening and postharvest disease management of major mango cultivars. Quantity loss (unmarketable fruit) was around 20% while quality loss (affecting price) was 65 and 70% in Sindhri and Samar Bahisht Chaunsa mango, respectively. Sap burn and postharvest diseases were the most important fruit quality issues at retail. Cultivars differed in terms of fruit harvest maturity indicators, postharvest treatment response, controlled atmosphere conditions and temperatures for storage and ripening. Besides physical de-sapping (on racks), lime wash (de-stemming and dipping fruit in 0.5% lime solution for 2-3 min) was also found to be effective, with morning being the best time for fruit picking. Significant relationships of production locality, orchard management, nutrition (Ca, B and K) and pre-cooling were found with postharvest disease incidence. Postharvest hot-water fungicidal dip of Scholar (active ingredient (a.i.) fludioxonil), Amistar (a.i. azoxystrobin) and Sportak (a.i. procholaz) gave significant fruit disease control. An integrated approach of good production practices, right maturity, correct postharvest fungicidal treatments and pre-cooling was an effective strategy for reducing disease incidence and maintaining better shelf-life at retail. On the basis of R&D and interventions, significant improvement was brought to the local mango industry and export. Sindhri mangoes were sea-freighted commercially to the EU and UK with good fruit quality outturn and overall postharvest life of 40-45 days.

Efficacy, persistence and vector susceptibility to pirimiphos-methyl (Actellic® 300CS) insecticide for indoor residual spraying in Zanzibar

BackgroundIndoor residual spraying (IRS) of households with insecticide is a principal malaria vector control intervention in Zanzibar. In 2006, IRS using the pyrethroid lambda-cyhalothrine was introduced in Zanzibar. Following detection of pyrethroid resistance in 2010, an insecticide resistance management plan was proposed, and IRS using bendiocarb was started in 2011. In 2014, bendiocarb was replaced by pirimiphos methyl. This study investigated the residual efficacy of pirimiphos methyl (Actellic® 300CS) sprayed on common surfaces of human dwellings in Zanzibar.MethodsThe residual activity of Actellic 300CS was determined over 9 months through bioassay tests that measured the mortality of female Anopheles mosquitoes, exposed to sprayed surfaces under a WHO cone. The wall surfaces included; mud wall, oil or water painted walls, lime washed wall, un-plastered cement block wall and stone blocks. Insecticide susceptibility testing was done to investigate the resistance status of local malaria vectors against Actellic 300CS using WHO protocols; Anopheline species were identified using PCR methods.ResultsBaseline tests conducted one-day post-IRS revealed 100 % mortality on all sprayed surfaces. The residual efficacy of Actellic 300CS was maintained on all sprayed surfaces up to 8 months post-IRS. However, the bioassay test conducted 9 months post-IRS showed the 24 h mortality rate to be ≤80 % for lime wash, mud wall, water paint and stone block surfaces. Only oil paint surface retained the recommended residual efficacy beyond 9 months post-IRS, with mortality maintained at ≥97 %. Results of susceptibility tests showed that malaria vectors in Zanzibar were fully (100 %) susceptible to Actellic 300CS. The predominant mosquito vector species was An. arabiensis (76.0 %) in Pemba and An. gambiae (83.5 %) in Unguja.ConclusionThe microencapsulated formulation of pirimiphos methyl (Actellic 300CS) is a highly effective and appropriate insecticide for IRS use in Zanzibar as it showed a relatively prolonged residual activity compared to other products used for the same purpose. The insecticide extends the residual effect of IRS thereby making it possible to effectively protect communities with a single annual spray round reducing overall costs. The insecticide proved to be a useful alternative in insecticide resistance management plans.

Development and analysis of mineral based coatings for buildings and urban structures

Commonly used materials in the construction of the building façades located in warm climates, often entrap a great amount of heat from the incoming solar radiation, leading to a respective thermal increase in the interior. The aim of the present study is to examine mineral-based coatings as a passive solar technique that contributes to buildings’ energy efficiency. A series of mineral based samples are developed and tested. Their thermal performance is estimated by infrared thermography and surface temperature measurements. Their optical properties are also measured while the energy efficiency is quantified using simulation techniques. The results revealed that renders based on hydraulic and/or hydrated lime with additions of calcium carbonate powder, as well as mineral paints comprised either of lime wash or silicate minerals can behave as cool coatings and contribute to a significant reduction of the cooling demand in warm climates.

Restauración de la fachada sur de Horní Hrad del castillo estatal de Český Krumlov

<p>El enfoque respetuoso de esta intervención, que ha considerado a la fábrica histórica como un testimonio genuino de su autenticidad y ha respetado en consecuencia todas las trazas e improntas de su estratificación, constituye un excelente botón de muestra para otras intervenciones de restauración en fachadas de edificios y monumentos. El uso de técnicas y materiales tradicionales como la consolidación con agua de cal ha garantizado la compatibilidad y la reversibilidad de la intervención. El proceso de ejecución representa igualmente un magnífico ejemplo de coordinación en una obra de restauración de gran envergadura.</p>

Brief Comments on the Restoration of the Monument of Adrian VI in Santa Maria dell’Anima in Rome

This contribution describes in detail the 1999 restoration of Pope Adrian’s tomb in Santa Maria dell’Anima, the church of the German nation. This restoration concentrated on various elements. The removal of atmospheric particles, high in reactive pollutants, to whose action, marble is particularly sensitive; the traces of lime wash, repainting, modified substances, filling materials not ideal for conservation and stains due to the iron and bronze elements. The elimination of these elements revealed the delicate colouring and the transitions that the material and the passing of the years have given to this excellent piece of Renaissance sculpture by Baldassarre Peruzzi.

Rediscovering the palette of Alentejo (Southern Portugal) earth pigments: provenance establishment and characterization by LA-ICP-MS and spectra-colorimetric analysis

Colored earth pigments sourced from Alentejo, Portugal, can be geologically categorized as either weathered carbonate rocks (terra rossas), schist units, or weathered iron ore deposits. The material was used until the mid-1900s by local residents as an ingredient in their traditional lime wash paintings and possibly in the production of artistic murals across the Alentejo region since pre-historic times. An integrated methodology incorporating laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and spectra-colorimetric analysis (CIELAB coordinates and reflectance curves), complemented by XRD, WDXRF, SEM-EDX, optical microscopy, and granulometric analysis, was used to characterize thirty-one Alentejo colored earths in an effort to correlate provenance with pigments properties. Data obtained from elemental analysis (major and trace) revealed a generic and similar elemental “fingerprint” that unable their distinction according to geographic provenance. Samples of weathered iron ore deposits derived from explored iron, copper, and sulfur mines are more easily discriminated using the chalcophilic (“sulfur-loving“) elements. Color analysis revealed a range of hues; olive-yellow to dark reddish-brown owing mainly to differences in the type and proportion of the color component present, independent of the accessory mineral.

Chafarizes do Largo de São Mamede e de Alconchel, em Évora: anotações metodológicas à sua recuperação e a descoberta, conservação e restauro de pintura mural

Com vista à protecção do património hidráulico de Évora, foi desenvolvido um projecto de restauro de dezoito estruturas, de diferentes tipologias (fontes, bicas e chafarizes), que se caracterizam pela sua diversidade em valor histórico e estado de conservação. O principal objectivo deste trabalho promovido pela Câmara Municipal de Évora e desenvolvido pela Nova Conservação, Lda. foi a conservação, o restauro e a reactivação das referidas estruturas, de modo a devolvê-las ao público. Nesta exposição, apresentam-se a metodologia e procedimentos efectuados para a sua recuperação, com destaque para os Chafarizes do Largo de São Mamede e, em particular, de Alconchel, devido à descoberta de pintura mural decorativa a fresco (

Phosphonate controls sudden oak death pathogen for up to 2 years

Since its emergence in the late 1990s, sudden oak death has killed mature oak trees and tanoaks in 14 California counties. Treatment options are now available to safeguard these trees from infection by Phytophthora ramorum, the aggressive and exotic pathogen responsible for sudden oak death. We provide an update on current knowledge regarding this emergent disease in California, and present results from three controlled experiments of two chemical treatments to manage the disease in oaks and tanoaks. Phosphonate treatments, legally registered in California to control sudden oak death, were effective in slowing both infection and growth rates for at least 18 months. Conversely, an alternative method consisting of an azomite soil amendment and bark lime wash was always ineffective, and did not reduce either growth or infection rates.

Earth mortars and earth-lime renders

As superficies arquitectonicas em terra desempenham um papel decorativo, para alem da funcao meramente protectora dos paramentos. Na arquitectura vernacula portuguesa, as argamassas em terra eram tradicionalmente usadas na elevacao de paredes em alvenaria de pedra, enquanto os rebocos em terra eram aplicados nas paredes interiores. A pedra calcaria existe apenas em algumas zonas do pais e consequentemente a cal nao estava disponivel, especialmente nas regioes de xisto e granito onde a alvenaria em pedra era uma tecnica corrente. Na regiao centro litoral de Portugal, o procedimento para extinguir a cal consistia na mistura de terra arenosa com cal aerea viva, posteriormente regada e usada como argamassa e reboco. Este era tambem o procedimento para estabilizar as terras usadas na producao de adobes. Os edificios construidos em adobe eram posteriormente rebocados com argamassas em cal e terra e decorados com argamassas de cal em pasta e areia muitas vezes com acabamento colorido em barramento de cal. A ornamentacao do tipo classico na arquitectura em terra dos seculos XVIII e XIX foi em muitos paises influenciada pelo manual de Francois Cointeraux (1740-1830) - Les Cahiers d'Architecture Rurale (1793), um guiao frances para a construcao e arquitectura em terra. Este manual chegou a Portugal no inicio do seculo XIX, mas nunca foi traduzido para a lingua portuguesa. Referencias a decoracao para as casas construidas em terra sao devidamente explicadas neste manual, assim como os procedimentos para a aplicacao de argamassas em terra e cal na ornamentacao das paredes em terra. De facto essas indicacoes sao coincidentes com as que encontramos na arquitectura de adobe em Portugal na regiao do centro. O objectivo deste artigo e mostrar alguns casos de argamassas e rebocos em terra existentes na arquitectura vernacula elevada em alvenaria de pedra e explicar os metodos usados na producao de argamassas em terra e cal, assim como exemplos de rebocos existentes na arquitectura vernacula de adobe em Portugal.

Yellow and red ochre pigments from southern Portugal: Elemental composition and characterization by WDXRF and XRD

Three different yellow and red ochre pigments geological sources from Alentejo— Terras rossas, schist units and weathered iron ore deposits—were studied by elemental and phase analysis complemented with Munsell and CIELAB colour parameters. Central aims were to underline the mineralogical and chemical distinctiveness of natural pigment sources and establish a connection between local geology and use of specific colour pigments in traditional lime wash mural paintings. According to the chemical composition the Fe abundance is 6 times higher than average crust values. The Terras Rossas are characterized by higher Ca contents. In yellow and red schists, phyllosilicates are major minerals, so pigments from these units are enriched in K and Rb. Besides Fe, the pigments from weathered ores are enriched in metals like Pb, As, Cu, and Zn, which can be used as fingerprints.

Raman microprobe analysis of stucco samples from the buildings of Maya Classic Copan

Micro-Raman spectroscopy has been applied to painted stucco samples from three buildings at the Maya site of Copan, Honduras. The buildings, Clavel (AD 450–550), Ani (AD550–650) and Structure 10L-22 (AD730,) date from three phases of the Classic Period (AD400–820) acropolis construction. The red pigment has been identified as haematite and the stucco as a mixture of calcite particles dispersed throughout a calcite based lime wash stucco. The physical structure of the stucco changed through time, indicating a refining of production techniques over this period. By combining Micro-Raman spectroscopy with other micro-ATR infrared spectroscopy and environmental scanning electron microscopy a detailed investigation of the materials and production techniques used to decorate these buildings has been made. Differences in the mineralogy of the red pigment used on each building indicate a different geological pigment source for each period.

The formation of alite phase by using phosphogypsum and oil shale

This study aims at gaining in-depth knowledge for the cement clinker production by utilizing phosphogypsum (PG) and oil shale (OS) as raw materials. The raw mixtures (Raw Mixes I and II) were burnt in a muffle furnace and then analyzed by X-ray diffraction (XRD) to observe the phases obtained. While minor amounts of alite (C 3S) and major amounts of anhydrite phases were observed with the Raw Mix I containing 40.72% PG refined with water and lime wash by two and three times, respectively (PGR 23), in N 2 atmosphere at 1300 °C, minor amounts of alite (C 3S), free CaO and major amounts of anhydrite phases were formed in air atmosphere at 1300 °C with the Raw Mix II containing 40.72% PG refined with water and lime wash by three and four times, respectively (PGR 34). The change of burning medium and the increase in the number of wash with water and lime, respectively, resulted in any difference in terms of the formation of the alite peaks; however, the intensity and the amount of anhydrite peaks were decreased in N 2 atmosphere due to the more conversion of that to the oxide compared to that in air atmosphere.

High-performance, marble-like plaster coatings

Conventional plaster coatings based on lime wash, cement paints, and resins offer decorative look with varying degree of water proofing. However, these coating surfaces usually undergo weather-induced deteriorations due to chemical and physical changes that lead to chipping, peeling off, and development of shrinkage cracks. To overcome these problems, a composite formulation, which contains more than 80% marble powder as inorganic graded filler with small amount of hydraulic components, has been developed. The uniform application of these composite pastes on masonry-plastered surfaces, result in a marble-like surface after the hardened coat is polished. The Mohs hardness of the developed, hardened, and polished coating surface was found to be >5. The coating was observed to retain dimensional stability and hardness when exposed to elevated temperature conditions (∼60°C) over long periods. After 2 years of exposure to various weather conditions, the external wall plasters did not shown any sign of deterioration. The mineralogy and morphology of the coating surfaces have been found to be comparable to that of an eggshell.

ASSESSMENT OF RECENT SURFACE CONSOLIDATION AND PROTECTION TREATMENTS ON SELECTED ARCHAEOLOGICAL MONUMENTS IN ROME

ASSESSMENT OF RECENT SURFACE CONSOLIDATION AND PROTECTION TREATMENTS ON SELECTED ARCHAEOLOGICAL MONUMENTS IN ROME

THE EFFECT OF ANTI-TRANSPIRANTS ON THE YIELD OF COTTON

An experiment in cotton MCU.7 was conducted to study the effect of anti transpirants like Kaolin, PMA, Cowdung slurry, Gurel, Liquid paraffin, Sandovit, Power Oil and Lime wash on the Kapas yield and its components, for three years from summer 1986 to 1988. The treatment differences for kapas yield, number of symposia/plant and number of bolls/plant were significant. Consistently higher kapas yield was obtained in the plots sprayed with Kaolin 3%. The crop received Liquid paraffin 1%, Cowdung slurry 5% and Gruel 1% sprays were also recorded considerably higher kapas yield. The ancillary data revealed that the higher kapas yield would have been achieved through number of symposia and number of bolls contributed by the physiological factors like high RWC and low stomatal count.

The restoration of buildings constructed with Menorcan limestone

Summary Accelerating weathering of the stonework of an 18th century building in Mahó n, Menorca, has given cause for concern. The nature and causes of the deterioration of the limestone were studied by X-ray diffraction, partial chemical analysis, differential thermal analysis and scanning electron microscopy. In the light of the results the following recommendations could be made with some confidence: replacement of most affected blocks by the more resistant dolomite; replacement of less deteriorated limestone by a tinted mortar; and the provision of a sacrificial coating of a lime wash.