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Fires are becoming more violent and frequent resulting in major economic losses and long-lasting effects on communities and ecosystems; thus, efficient fire monitoring is becoming a necessity. A novel triple multi-sensor approach was developed for monitoring and studying the burning of dry forest fuel in an open field scheduled experiment; chemical, optical, and acoustical sensors were combined to record the fire spread. The results of this integrated field campaign for real-time monitoring of the fire event are presented and discussed. Chemical analysis, despite its limitations, corresponded to the burning process with a minor time delay. Nevertheless, the evolution profile of CO2, CO, NO, and O2 were detected and monitored. The chemical monitoring of smoke components enabled the observing of the different fire phases (flaming, smoldering) based on the emissions identified in each phase. The analysis of fire acoustical signals presented accurate and timely response to the fire event. In the same content, the use of a thermographic camera, for monitoring the biomass burning, was also considerable (both profiles of the intensities of average gray and red component greater than 230) and presented similar promising potentials to audio results. Further work is needed towards integrating sensors signals for automation purposes leading to potential applications in real situations.

In wildland fires where water is used as the primary extinguishing agent, one of the issues of wildfire suppression is estimating how much water is required to extinguish a certain section of the fire. In order to use easily distinguished and available indicators, the flame length and the area of the active combustion zone were chosen as suitable for the modelling of extinguishing requirements. Using Byram’s and Thomas’ equations, the heat release rate per unit length of fire front was calculated for low-intensity surface fires, fires with higher wind conditions, fires in steep terrain and high-intensity crown fires. Based on the heat release rate per unit length of fire front, the critical water flow rate was calculated for the various cases. Further, the required amount of water for a specific active combustion zone area was calculated for various fuel models. Finally, the results for low-intensity surface fires were validated against fire experiments. The calculated volumes of water can be used both during the preparatory planning for incidents as well as during firefighting operations.

Raw earth, like wood and stone, is one of the oldest building materials used across the world. Nowadays, given the growing role of circular economy, researchers are ever more interested in raw earth-based building materials, because they are widely available and environmentally friendly. The use of this traditional material has positive environmental consequences, especially in traditional rural building reuse and in rural landscape preservation. In fact, raw earth is locally available and totally recyclable and, thanks to its perfect integration into the landscape, it improves site visual perception. Additives and/or chemical stabilizer agents (i.e., Portland cement) are often used in the production of raw earthbased building components in order to increase their mechanical performance and durability. This production process reduces the environmental sustainability of the base material and causes a relevant increase on the embodied energy (i.e., the total energy required for the extraction, processing, manufacturing, and delivery of building components). This research work aimed at investigating how to improve the mix-design of earth-based building materials in order to increase their mechanical properties without any addition of chemical agents. A physical stabilization was performed on an original texture soil by adding various particle sizes. Mechanical tests were carried out on five different soil mixes by changing soil composition, aggregates, and water. Specimens made with mix-design 5 offered the best results in terms of flexural and compressive strength values which were 1.65 MPa and 6.74 MPa, respectively. Mix 3 obtained the lowest linear shrinkage rate (6.04%). Since raw earth-based materials are highly sensitive to soil composition and aggregates, this study attempted to obtain a repeatable process to produce semi-industrial adobes by optimizing and controlling various natural materials (i.e., soils, aggregates, and water).

The inhibitory effect of antimicrobial zeolite coated concrete specimens (Z2) against Acidithiobacillus thiooxidans was studied by measuring biomass dry cell weight (DCW), biological sulphate generation, and oxygen uptake rates (OURs). Uncoated (UC), and blank zeolite coated without antimicrobial agent (ZC) concrete specimens were used as controls. The study was undertaken by exposing inoculated basal nutrient medium (BNM) to the various specimens. The coating material was prepared by mixing zeolite, epoxy and cure with ratios, by weight of 2:2:1. Concrete specimens were characterized before and after exposure to inoculated or sterile BNM by field emission-scanning electron microscopy (FE-SEM). Gypsum, which was absent in the other test concrete specimens, was detected in uncoated specimens exposed to the bacterium. In UC and ZC, the growth of the bacteria increased throughout the duration of the experiment. However, significant biomass inhibition was observed in experiments where Z2 was used. The overall biomass growth rate in suspension before the specimens were placed ranged from 3.18 to 3.5 mg DCW day(-1). After the bacterium was exposed to UC and ZC, growth continued with a corresponding value of 4 + or - 0.4 and 5.5 + or - 0.6 mg DCW day(-1), respectively. No biomass growth was observed upon exposure of the bacterium to Z2. Similarly, while biological sulphur oxidation rates in UC and ZC were 88 + or - 13 and 238 + or - 25 mg SO(4)(2-) day(-1), respectively, no sulphate production was observed in experiments where Z2 concrete specimens were used. Peak OURs for UC and ZC ranged from 2.6 to 5.2 mg l(-1) h(-1), and there was no oxygen uptake in those experiments where Z2 was used. The present study revealed that the antimicrobial zeolite inhibits the growth of both planktonic as well as biofilm populations of Acidithiobacillus thiooxidans.

Исследована двойная циклодегидратация D‑сорбита до изосорбида на сульфокатионитах Amberlyst‑15 и КУ‑2‑8 при 120‑140 oC в реакторе периодического действия под вакуумом (150‑170 мбар) без растворителя. Установлено, что исследуемые катализаторы обеспечивают 78‑88% выход изосорбида с полной конверсией сорбита при 140 °С за 3 часа. Более стабильный Amberlyst 15 продуцирует 10 г изосорбида на 1 г катализатора за 3 часа при 130 °С. После 5 экспериментов в течение 3 ч при 125 oC концентрация кислотных центров на поверхности Amberlyst 15 снижается лишь на 4 %, конверсия сорбита и выход продуктов остаются почти неизменными. КУ‑2‑8 обеспечивает высокую начальную каталитическую активность, но после лишь одного цикла эта смола теряет 40 % сульфогрупп. Досліджено подвійну циклодегідратацію D‑сорбіту до ізосорбіду на сульфокатіонітах Amberlyst 15 та КУ‑2‑8 при 120‑140 oC у реакторі періодичної дії під вакуумом (150‑170 мбар) без розчинника. Встановлено, що досліджувані каталізатори забезпечують 78‑88 % вихід ізосорбіду з повною конверсією сорбіту при 140 оС за 3 год. Більш стабільний Amberlyst 15 продукує 10 г ізосорбіду на 1 г каталізатора за 3 год при 130 оС. Після 5 експериментів протягом 3 год при 125 oC концентрація кислотних центрів на поверхні Amberlyst 15 знижується лише на 4 %, конверсія сорбіту та вихід продуктів залишаються майже незмінними. КУ‑2‑8 забезпечує високу початкову каталітичну активність, але лише після одного циклу ця смола втрачає 40 % сульфогруп. The double cyclodehydration of D‑sorbitol to isosorbide on Amberlyst 15 and KU‑2‑8 sulfonic acid resins at 120‑140 оC in the batch reactor under vacuum (150‑170 mbar) without solvent was studied. It was found that the studied catalysts provide 78‑88 % isosorbide yield with a complete conversion of sorbitol at 140 оC for 3 h. More stable Amberlyst 15 produces 10 g of isosorbide per 1 g of catalyst for 3 h at 130 оC. After 5 experiments for 3 h at 125 oC acid site concentration on Amberlyst 15 surface reduced by only 4 %, sorbitol conversion and yield of products remain almost unchanged. KU‑2‑8 shows high initial catalytic activity, but after only one run this resin loses 40 % of sulfonic groups.

Fire protection is a basic safety issue for all categories of buildings. The criteria for effective fire suppression and the characteristics of extinguishing systems in insulated areas depend on a combination of factors. The main influences include the type of combustible material, ambient temperature, type of spray extinguisher, air inflow and outflow conditions, and space geometry. This article analyzes the most widely used fire-extinguishing technologies in different locations. The main aspects of using the pulsed delivery technology of extinguishing liquid are considered. Based on the analysis of publications from the last decade, it is possible to develop intelligent systems for recording fires and extinguishing fires in the premises.

Abstract Pyrolysis is a key process in all stages of wood burning from ignition to extinction. Understanding each stage is crucial to tackle wildfires and assess the fire safety of timber buildings. A model of appropriate complexity of wood pyrolysis and oxidation is missing, which limits the understanding of fires fuelled by wood. Progress towards this aim has been slow in recent years, as the role of chemical kinetics is still debated. Three predominant theories hypothesis that chemistry is either infinitely fast (de Ris), a function of char depth (Atreya), or a function of heat flux (Suuberg). This paper proposes a novel multi-scale model of wood pyrolysis and oxidation for predicting the charring of timber. The chemical kinetics sub-model was previously validated at the microscale (mg-samples). We favourably compare the complete model against a large range of mesoscale experiments (g-samples) found in the literature of different moisture contents (0–30%), heat fluxes (0–60 kW/m2), oxygen concentrations (0–21%), grain directions (parallel/perpendicular), and combinations thereof. The model was then used to calculate the transient Damkohler number of wood at different depths and heat fluxes. This analysis showed that chemistry and heat transfer are both important at all heat fluxes and stages of burning relevant to fire, which unifies the three theories by Suuberg, Atreya, and de Ris. We argue that the model is of currently appropriate complexity to predict the charring of timber. These findings improve our understanding of wood pyrolysis and the modelling of timber burning across scales.

In recent years the demand for sustainable materials in all technical fields has become increasingly urgent. This trend also applies to the building industry, which is striving for climate-friendly construction. Hence, the renewable and fast-growing material bamboo is a very promising solution. To bring bamboo closer to a potential application, a key interest is to teach the next generation of architects and civil engineers about the material, its properties and its behavior. Students from the RheinMain University of Applied Sciences in Wiesbaden, Germany, were invited to join lectures teaching them from conceptualization to the completion of a building made of bamboo. The aim was to create awareness and familiarity with this sustainable material for subsequent applications. Additionally, the students were given the chance to work with bamboo practically. For several months, trial investigations of the basic mechanical properties of bamboo culms were undertaken with the students. The experimental research included measurement of the moisture content, compression tests, and fractography. Knowledge about material properties and their determination should be brought to the students who are mostly unfamiliar with material testing. Based on the values measured during mechanical testing, the students should be able to do exemplary load-bearing calculations for the bamboo material.