1,720,987 research outputs found
Comparison of different storage systems of softwood biomass and urban pruning residues
No full textRenewable biomass play a crucial role in mitigating climate change as a potential alternative for fossil fuels. On the other hand, lignocellulosic biomass can represent an enormous natural resources to use for energetic field. In fact, the use of fossil fuels as a main source of energy is directly linked to global climate change, so there is a necessity to find new, cheap and easily available energy sources. This study demonstrated the influence of storage system on the quality of different biomass for energy generation. Softwood biomass and urban pruning residues were used to investigate the behavior of two different storage system, such as plastic bins and big bags. Principal parameters of the biomass, such as variation the moisture content inside each storage system, temperature, presence or absence of microorganisms able to reduce the energetic properties of biomass and weather condition were recorded. Both types of biomass were stored outside and partially left exposed to the weather conditions for five months. The variations of the moisture content of each type of biomass stored, showed no significant effects. Only the wood chips stored within the plastic bins, demonstrated a general decrease of the moisture content, compared to other wood biomass. The results present one of the most widely used biomass storage methods focusing the main role of storage system within the various supply chain stages. Furthermore, can be a support to identify the critical storage related issues
An alternative method for the assessment of wood machinability and optimization of the cutting process
No full textSteaming treatment decreases moe and compression strength of Turkey OAK wood
No full textThis study examined the mechanical properties of Turkey oak (Quercus cerris L.) wood before and after combined steam and thermal treatments under vacuum conditions. Wood was steamed at 100 to 110° C and thermally treated under vacuum at 160° C by the press-vacuum or thermo-vacuum process. Treated material was characterized in terms of the modulus of elasticity (MOE) and compression strength of heartwood and sapwood. The MOE was established using a nondestructive technique based on the measurement of ultrasonic pulse propagation. Results differed depending on the treatment or combination of treatments, and showed that the steaming process strongly affected the MOE. Thermo-vacuum treatment increased the compression strength, whereas steaming had the opposite effect
Bioactive compounds achieved from residues of the apricot tree (Prunus armeniaca L.) and olive tree (olea europaea L.): New prospective in the industrial sector
No full textIn recent years, much thought has been given to how to use woody biomass to develop a value chain linked to it. Very often, however, the use of biomass has continued to be associated with the production of energy and heat. The purpose of this study is to demonstrate how woody biomass from apricot (Prunus armeniaca L.) and olive groves (Olea europaea L.) can have further applications in sectors beyond the use to produce energy. The biomass includes pruning residues (branches) and trunk residues obtained once the cultivations explantation. altogether samples were separated from the bark from the wood and within the cases of apricot, the trunk was has separated the hardwood from the sapwood. These samples first were cut into little items, then ground to get wood. Extraction of wood was performed by mistreatment an Accelerated Solvent Extractor (ASE) with 3 sorts of solvent: Ethanol, water, and a mixture of ethanol:water (50:50 v/v). The chemical analyses of the extracts were performed employing a liquid chromatography-mass chemical analysis (LC-MS). The results showed the yields of the extractives and therefore the secondary metabolites present in each sample. Secondary metabolites are chemical compounds produced by several plant tissues (e.g. leaves, bark, roots, buds, wood) that offer different medicative applications, together with inhibitor, anticancer, medicinal drug, antifungal, and different properties. The investigation of the natural compounds although isn't a simple procedure, attention-grabbing natural compounds as catechine and oleuropein were found within the samples of biomass
Effects of thermo-vacuum treatment on secondary metabolite content and antioxidant activity of poplar (Populus nigra L.) wood extracts
No full textA renewed interest in producing thermo-treated wood extracts and the potential applications of these extracts was observed in chemical, pharmaceutical, and food industries. Poplar (Populus spp.), belonging to the Salicaceae family, is one of the most cultivated woody plant for industrial purposes, one of the least expensive hardwoods, rarely used in the production of fine furniture, but extensively used for pulp and panel productions and have therefore an important economic impact worldwide. The aim of this study was to verify the influence of thermo-vacuum treatment (at 180, 200, and 220 °C) on wood extracts obtained via three different extraction techniques: maceration, ultrasound-assisted extraction and accelerated-solvent extraction. Effect of temperature on extraction was verified by measuring the total contents of polyphenols, tannins and flavonoids. Secondary metabolites are often related to antioxidant activity measured by several in vitro tests, including the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging method, the ferric-reducing-ability power test, and the beta-carotene bleaching assay. Our results showed the presence and the effect of heat treatments and extraction techniques on polyphenol and flavonoid contents. Extracts obtained from wood heated at 200 and 220 °C showed the highest flavonoid and polyphenol contents, and, we observed a relationship with the shown antioxidant activity levels. Our study clearly showed the differential effects of temperature and extraction technique on both antioxidant activity and secondary metabolite contents. The detailed knowledge about the extractives from poplar wood can contribute, on the one hand, to better understand the effect of temperature during thermo treatment, and, on the other demonstrates the potential of this species as a source of bioactive compounds for nutraceutical or pharmaceutical applications by identifying appropriate extraction techniques
Gallic acid as main product in the water extractives of Quercus frainetto ten
No full textThe autoclave extraction of Hungarian oak (Quercus frainetto Ten.) wood gave 5.3% extractives. The chloroform soluble fraction obtained from the extracts of Q. frainetto allows to identify sesamin. The insoluble fraction contains mainly ribose and mannose. Water extraction in autoclave of thermo-treated Q. frainetto wood gave a lower amount of extractives (3.31%). The main product of the insoluble fraction was, on the basis of its mass spectrum, the monoacetyl derivative of gallic acid
Thermal treatment modifies the calorific value and ash content in some wood species
No full textThermo-treated wood is a new material that has recently been introduced to the market. Thus, the increase in the amount of treated wood in the wood industry and in the interior of buildings creates demands for the evaluation of its fire risk. However, few evidences have yet been published on the calorific evaluation and fire load, required in case of building code, for thermo-treated wood products. The main goal of this research was to evaluate how different treatments affect the calorific values and the relative ash content for three cases of thermo-treated woods (Norway spruce, Common ash, and Turkey oak). Norway spruce and Common ash were thermally treated at 190 °C for two hours. Turkey oak logs were initially steamed at 110 °C for 24 h, dried until the 0% of moisture content and then thermo treated at 160 °C for three hours. Low and High calorific values (LCV, HCV) and ash content were evaluated. Ash content and HCV are related to dry mass. After thermo-treatment, the LCV and HCV increased, while the ash content changed significantly in Turkey oak
Thermo-treatment affects Quercus cerris L. wood properties and the antioxidant activity and chemical composition of its by-product extracts
Full text linkNowadays, there is an increasing interest on thermo-treatment and its effects on wood structure and extraction processes, connected to the wood use for industrial application and for its use as biorefinery. The present investigation aimed to provide the main changes on wood properties (mass loss, color variation and modulus of elasticity) and a comparative analysis of the antioxidant properties and GC–MS profile of the extracts from Turkey oak (Quercus cerris L.) wood. Untreated and thermo-treated wood (170 °C x 3 h) samples were compared. Thermo-treatment induced a mass loss (5.1%) in wood, a darkening of color surface (ΔE = 7.6) and a decrease of MOE (4.1%). Moreover samples were extracted using different techniques: maceration (ME), ultrasound assisted extraction (UAE) and accelerated solvent extraction (ASE). Extracts were tested to evaluate the content of polyphenols and flavonoids along with the in vitro antioxidant activity. Results showed that extracts obtained from thermo-treated wood reported the highest Relative Antioxidant Capacity Index and extraction techniques affected the value in the following rating: UAE > ME > ASE. Qualitative and quantitative measurements of chemical compounds were carried out by GC–MS system. Taking into account the thermo-treatment and extraction techniques, principal component analysis (PCA) was performed also in order to evaluate the relationships among principal chemical compounds. According to results obtained, thermo-treatment and extraction technique had a determinant role in the antioxidant efficiency and, consequently, on the potential application of extracts
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