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Solar water distillation is an effective technology for producing potable water using sustainable energy sources. However, the widespread use of this technology in industrial and domestic applications is hindered by low daily production compared to other methods. In this study, a new modification was introduced by placing a hollow cylinder inside a solar distiller and then integrating the cylindrical solar distiller with a solar heater (modified solar still). An economic analysis and study of the chemical and physical properties of the modified solar still (MSS) were carried out. The MSS produced a 296–300% increase in distillate water yield compared to a commercial solar still (CSS) on 17 July 2019, and reached 400% in other months depending on weather conditions. The costs of producing a liter of distilled water from the conventional and modified solar stills were 0.0282 and 0.0268 $/lit, respectively. Thus, the proposed solar distiller design is economically feasibile, reducing the cost of production compared to a conventional distiller and previous studies. The distillate water produced by the MSS and CSS has given the best results to all TDS, pH, and electrical conductivity tests according to local and international standards. © 2021 The Authors.

Lignin has gained interest in academia as a rawmaterial for advancedmaterials such as thermosets. Attractive features include its natural and technical abundances, its structural compositions, distribution of functionalities and most importantly its origin from renewable sources, i.e. lignocellulosic biomass. In this chapter, we will focus on lignin-based thermosets, specifically reviewing the recent strategies for such applications in polyurethanes, phenol-formaldehyde resins and epoxy thermosets. In these contexts, the advantages and competitiveness of lignin over conventional petrol-based will be discussed based on comparisons with benchmark properties. The chapter emphasizes the unique polymer chemistries adopted by different researchers, the effects of the chemical and physical properties of lignin on both reactivities during synthesis and thermomechanical properties of materials. Furthermore, the direct use of lignin in the unmodified state is contrasted with the use of selectively modified lignins in these polymer systems. The use of multifunctional lignin oligomers as raw material is also contrasted with the use of lignin platform monomers obtained through de-polymerization approaches. Finally, the challenges of lignin or monomers thereof, as a raw material in these applications are discussed to direct the future outlook of this research area., QC 20220209

A study of steel-arch support corrosion caused by highly mineralised water and aggressive underground atmospheres in the Ziemowit part of the Piast-Ziemowit coal mine in Poland is presented. Physical and chemical properties of water in the Ziemowit part and general hardness data for natural waters are discussed. Reconstruction of continuously degraded steel-arch supports by dry application of a polypropylene-fibre-reinforced shotcrete strengthening layer is described., A study of steel-arch support corrosion caused by highly mineralised water and aggressive underground atmospheres in the Ziemowit part of the Piast-Ziemowit coal mine in Poland is presented. Physical and chemical properties of water in the Ziemowit part and general hardness data for natural waters are discussed. Reconstruction of continuously degraded steel-arch supports by dry application of a polypropylene-fibre-reinforced shotcrete strengthening layer is described.

Context. The Upper-Scorpius association (5 11 Myr) contains a unique population of low-mass (M< 30 MJup) brown dwarfs either free-floating, forming wide pairs, or on wide orbits around solar-type and massive stars. The detailed relative characterization of their physical properties (mass, radius, temperature, composition, and ongoing accretion) offers the opportunity to potentially explore their origin and mechanisms of formation. Aims. In this study, we aim to characterize the chemical and physical properties of three young, late-M brown dwarfs claimed to be companions of the Upper-Scorpius stars USco 161031.9-16191305, HIP 77900, and HIP 78530 using medium-resolution spectroscopy at UV (0:300:56 m; R 3300), optical (0:551:02 m; RA - 5400), and NIR (1:022:48 m; RA - 4300) wavelengths. The spectra of six free-floating analogs from the same association are analyzed for comparison and to explore the potential physical differences between these substellar objects found in different configurations. We also aim to examine and analyze hydrogen emission lines at UV and optical wavelengths to investigate the presence of ongoing accretion processes. Methods. The X-shooter spectrograph at VLT was used to obtain the spectra of the nine young brown dwarfs over the 0:32:5 mrange simultaneously. Performing a forward modeling of the observed spectra with the ForMoSA code, we infer the Teff, log (g), and radius of our objects. The code compares here the BT-SETTL15 models to the observed spectra using the Nested Sampling Bayesian inference method. Mass is determined using evolutionary models, and a new analysis of the physical association is presented based on Gaia-DR2 astrometry. Results. The Teff and log (g) determined for our companions are compatible with those found for free-floating analogs of the Upper-Scorpius association and with evolutionary model predictions at the age of the association. However the final accuracy on the Teff estimates is strongly limited by nonreproduci

This paper presents the effects of agricultural wastes on the mechanical properties of lightweight foamed concrete, LFC. The agricultural wastes utilized in this research are banana skin powder (BSP) and palm oil fuel ash (POFA) as cement and sand replacement, respectively. Physical and chemical tests were conducted to determine the chemical composition and particle size of both BSP and POFA. These chemical and physical properties of the raw materials are important in understanding the effects they have on the mechanical properties of lightweight foamed concrete incorporating BSP and POFA, which is designated as LFC-BSP-POFA. Cube, cylindrical, and prism specimens of LFC-BSP-POFA with density of 1800kg/m³ were cast and tested to determine its compressive strength, tensile strength, modulus of elasticity and flexural strength. Twelve (12) LFC-BSP-POFA mixtures were prepared with content of BSP as cement replacement of 0%, 0.2%, 0.4%, 0.6%, 0.8% and 1% by weight. For each mixture, the content of POFA as sand replacement are 0% and 15%. It was found that BSP and POFA each contain 55.98% and 51.83% silicon dioxide, and 2.71% and 2.32% aluminum oxide, respectively. The particle size for these two materials as obtained from PSA test showed that both materials are considered as fine particles, which is within 0.1µm to 250 µm. These chemical composition and particle size of BSP and POFA contribute to the pozzolanic reaction in LFC. This is proven by the results obtained from the mechanical properties tests which show that the incorporation of both BSP and POFA as cement and sand replacement have some significant effects on the mechanical properties of LFC. The increase percentage of BSP and POFA incorporated in LFC had shown slight increment in its mechanical properties.

This paper presents the effects of agricultural wastes on the mechanical properties of lightweight foamed concrete, LFC. The agricultural wastes utilized in this research are banana skin powder (BSP) and palm oil fuel ash (POFA) as cement and sand replacement, respectively. Physical and chemical tests were conducted to determine the chemical composition and particle size of both BSP and POFA. These chemical and physical properties of the raw materials are important in understanding the effects they have on the mechanical properties of lightweight foamed concrete incorporating BSP and POFA, which is designated as LFC-BSP-POFA. Cube, cylindrical, and prism specimens of LFC-BSP-POFA with density of 1800kg/m³ were cast and tested to determine its compressive strength, tensile strength, modulus of elasticity and flexural strength. Twelve (12) LFC-BSP-POFA mixtures were prepared with content of BSP as cement replacement of 0%, 0.2%, 0.4%, 0.6%, 0.8% and 1% by weight. For each mixture, the content of POFA as sand replacement are 0% and 15%. It was found that BSP and POFA each contain 55.98% and 51.83% silicon dioxide, and 2.71% and 2.32% aluminum oxide, respectively. The particle size for these two materials as obtained from PSA test showed that both materials are considered as fine particles, which is within 0.1µm to 250 µm. These chemical composition and particle size of BSP and POFA contribute to the pozzolanic reaction in LFC. This is proven by the results obtained from the mechanical properties tests which show that the incorporation of both BSP and POFA as cement and sand replacement have some significant effects on the mechanical properties of LFC. The increase percentage of BSP and POFA incorporated in LFC had shown slight increment in its mechanical properties.

Each material has its own advantages and disadvantages in terms of its mechanical, chemical and physical properties. Metallic materials are comparatively ductile and easy to process. Fibre reinforced plastics are very stiff and endure high tensile stresses based on their weight. By intelligent combination of these materials into one overall-part light but strong components may be established. However, the conventional production of a separate fibre reinforced plastic (FRP)-component and a metal component and a subsequent joining is time- And labour-intensive and therefore not economical in mass-production. Thus in this paper a new fabrication technology is presented.

Each material has its own advantages and disadvantages in terms of its mechanical, chemical and physical properties. Metallic materials are comparatively ductile and easy to process. Fibre reinforced plastics are very stiff and endure high tensile stresses based on their weight. By intelligent combination of these materials into one overall-part light but strong components may be established. However, the conventional production of a separate fibre reinforced plastic (FRP)-component and a metal component and a subsequent joining is time- And labour-intensive and therefore not economical in mass-production. Thus in this paper a new fabrication technology is presented.

Fungal decay considerably affects the macroscopic mechanical properties of wood as a result of modifications and degradations in its microscopic structure. While effects on mechanical properties related to the stem direction are fairly well understood, effects on radial and tangential directions (transverse properties) are less well investigated. In the present study, changes of longitudinal elastic moduli and stiffness data in all anatomical directions of Scots pine (Pinus sylvestris) sapwood which was degraded by Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) for up to 28 weeks have been investigated. Transverse properties were found to be much more deteriorated than the longitudinal ones. This is because of the degradation of the polymer matrix between the cellulose microfibrils, which has a strong effect on transverse stiffness. Longitudinal stiffness, on the other hand, is mainly governed by cellulose microfibrils, which are more stable agains fungal decay. G. trabeum (more active in earlywood) strongly weakens radial stiffness, whereas T. versicolor (more active in latewood) strongly reduces tangential stiffness. The data in terms of radial and tangential stiffnesses, as well as the corresponding anisotropy ratios, seem to be suitable as durability indicators of wood and even allow conclusions to be made on the degradation mechanisms of fungi.

Fungal degradation alters the microstructure of wood and its physical and chemical properties are also changed. While these changes are well investigated as a function of mass loss, mass density loss and changes in equilibrium moisture content are not well elucidated. The physical and chemical alterations are crucial when linking microstructural characteristics with macroscopic mechanical properties. In the present article, a consistent set of physical, chemical and mechanical characteristics is presented, which were measured on the same sample before and after fungal degradation. In the first part of this two-part contribution, elucidating microstructure/stiffness-relationships of degraded wood, changes in physical and chemical data are presented, which were collected from specimens of Scots pine (Pinus sylvestris) sapwood degraded by Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) for up to 28 weeks degradation time. A comparison of mass loss with corresponding mass density loss demonstrated that mass loss entails two effects: firstly, a decrease in sample size (more pronounced for G. trabeum), and secondly, a decrease of mass density within the sample (more pronounced for T. versicolor). These two concurrent effects are interrelated with sample size and shape. Hemicelluloses and cellulose are degraded by G. trabeum, while T. versicolor was additionally able to degrade lignin. In particular because of the breakdown of hemicelluloses and paracrystalline parts of cellulose, the equilibrium moisture content of degraded samples is lower than that in the initial state.

Glyconanomaterials, broadly defined as carbohydrate-presenting structures below 100 nm in size, exhibit remarkable chemical and physical properties with high potential for modern biomedical applications. In this chapter, current synthetic approaches for fabricating glyconanomaterials are summarized, with special emphasis on a novel photocoupling strategy to conjugate carbohydrates onto a wide variety of nanomaterials. Based on the photochemically induced reaction of perfluorophenylazide, different glyconanomaterials were efficiently synthesized, and the resulting structures used in a range of applications. The results demonstrate that this approach to carbohydrate presentation at nanomaterial surfaces leads to efficient and selective binding to cognate proteins, enabling new applications in carbohydrate-lectin recognition, profiling, biosensing, screening, cell imaging, and bacteria detection., QC 20120214

[SPA] Los estudios relativos al manejo postcosecha de frutos de hortalizas y frutales son escasos en la región oriental de Venezuela, donde el producto cosechado se vende mayormente fresco, dado el desconocimiento que se tiene de técnicas apropiadas de conservación, que permitan darle valor agregado al producto fresco. El presente estudio tuvo como objetivo evaluar la características físico-químicas, en forma fresca y deshidratada, de pseudofrutos de merey (Anacardium occidentale L), especie frutal de gran importancia económica y social al oriente del país, y frutos de ají dulce (Capsicum chinense), de amplio uso en platos tradicionales venezolanos, que por su fragancia y sabor típico lo hacen de mayor demanda que el pimentón en la preparación casera de guisos, salsas y sopas en esta región. Los pseudofrutos de merey se cortaron en láminas de 3 mm de grosor y los frutos de ají se cortaron a la mitad, para ser posteriormente deshidratados en estufa a 65°C y 60°C respectivamente por 24 horas. Los resultados demostraron que en los cuatro muestreos efectuados, para ambos subproductos hortofrutícolas, las pérdidas de peso estuvieron por encima del 87 % de su peso inicial, con un rendimiento en peso sobre el 10%. Los contenidos de sólidos solubles incrementaron en promedio siete veces con respecto a su valor inicial, mientras que el pH no mostró ninguna diferencia significativa, manteniéndose alrededor de 4,6-4,8. La acidez expresada en ácido cítrico fue de 0,49/100g para los deshidratados de ají dulce y de 0,85/100g para aquellos de merey. La vitamina C, expresada como acido ascórbico, se redujo considerablemente, permaneciendo, sin embargo, en valores adecuados para ambos productos (104mg/100g para el deshidratado de ají dulce y 126mg/100g para los de merey). Todo esto es indicativo de la posibilidad de diversificar el producto final de estas especies, manteniendo la calidad de los mismos, luego de procesados. [ENG] Studies regarding postharvest management of vegetables

LEXFOAM is an explosive foam developed from two non-explosive components to replace C-4 or TNT in humanitarian demining. This paper discusses a recent break through in packaging, the properties of newly developed LEXFOAM and improvement in delivery based on deficiencies noted in field testing. The Hand-held delivery system consists of two disposable aerosol cans. A large aerosol can contains 500 gm of the LEXFOAM stock solution and a small aerosol can contains 60 gm of blended liquid hydrocarbon propellants. LEXFOAM develops only after mixing the two components on-site in the stock solution aerosol can. The LEXFOAM becomes an explosive only after the foam is been dispersed. This paper describes and discusses the physical-chemical properties of LEXFOAM produced by handheld systems and test results of their performance against a variety of unfuzed live mine targets. User interface, target mine types, effectiveness variation as a function of temperature, and potential applicability in humanitarian demining environments are discussed., The original document contains color images.