146 results on '"technical properties"'
Search Results
2. Properties and low-temperature performance of biomass heavy oil used in road applications
- Author
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Han-geng Sun, Yantao Hu, Heting Wang, and Zefu Xing
- Subjects
Bio-asphalt ,Biomass heavy oil ,Low-temperature properties ,Chemical components ,Technical properties ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Biomass heavy oil, a renewable green energy source, has been extensively explored for its preparation process and material properties. This study examined the applicability of biomass heavy oil integrated into matrix asphalt. Bio-asphalt samples were prepared using polymer-modified asphalt I-C as the matrix asphalt, blended with straw liquid oil, straw solid oil, and castor liquid oil. The low-temperature performances of these samples were assessed. First, the effects of bio-oil on the fundamental performance of asphalt were analyzed through three-component tests, encompassing a short-term aging test and a temperature scanning test based on dynamic shear rheometry. Subsequently, the effects of the chemical composition of bio-asphalt on its fundamental performance were examined through four-component tests, including SARA, gel-permeation chromatography (GPC), and gray entropy correlation. The glass transition temperature (Tg) was considered a parameter for evaluating the low-temperature properties of the bio-asphalt binders. The bending-beam rheometry (BBR) low-temperature creep test and the binder fracture energy (BFE) full-section fracture energy test revealed that adding bio-oil reduces Tg of the matrix asphalt. The integrated creep flexural parameter Jc and the BFE fracture energy density values indicated that the low-temperature fracture-resistant properties of bio-asphalt surpass those of the matrix asphalt. Furthermore, the low-temperature cracking resistance of the bio-asphalt samples was determined through the BFE test. Gray entropy correlation analysis of the low-temperature performance indicators of bio-asphalt revealed that the BBR test is suitable for evaluating low-temperature performance only up to − 12 °C. In summary, the bio-asphalt mixtures demonstrate exceptional fatigue resistance under low-temperature service conditions. Therefore, bio-oil emerges as an effective candidate for enhancing the low-temperature performance characteristics of matrix asphalt.
- Published
- 2024
- Full Text
- View/download PDF
3. Analytical Hierarchical Process as a Multicriteria Decision Tool in Material Selection for Prefabricated Wood Buildings.
- Author
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Cabral, Matheus R. and Blanchet, Pierre
- Subjects
WOODEN-frame buildings ,ANALYTIC hierarchy process ,DECISION making ,BURGLARY protection ,WELL-being - Abstract
The popularity of prefabricated wooden buildings is increasing in North America, but choosing suitable materials for these structures can be complicated. This can lead to problems like financial losses, production delays, and lower quality. Therefore, the main goal of this study was to use the Analytical Hierarchy Process (AHP) decision-making tool to rank the criteria for material selection for prefabricated wood buildings in Canada and the United States. The methodology involved surveys experts in the prefabricated wood construction industry from Canada and the United States. The data obtained from the questionnaires utilized for the AHP analysis were modeled using R programming language. The results revealed that for structural materials, the top five subcriteria were safety and security of building occupants (0.234), location, shape, and height of the building (0.218), comfort, satisfaction, and well-being of the building (0.155), occupant health (0.121), and availability of materials (0.098). For selecting envelope materials, the top five subcriteria were comfort, satisfaction, and well-being of the building (0.252), safety and security of building occupants (0.206), location, shape, and height of the building (0.178), occupant health (0.132), and availability of materials (0.078). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. Era of bast fibers-based polymer composites for replacement of man-made fibers
- Author
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Caroliny M. Santos, Thiago F. Santos, Marcos S. Aquino, Sanjay Mavinkere Rangappa, Suchart Siengchin, and Indran Suyambulingam
- Subjects
Mechanical properties ,Extraction process ,Chemical compositions ,Technical properties ,Industrial applications ,Green-composites ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Bast fibers are defined as those obtained from the outer cell layers of the bast of various plant families. They are finding use in textile applications and are widely used as reinforcements for green composites, as bast fibers are perceived as “sustainable”. There is a growing demand for bast fibers across the world due to their renewable and biodegradable nature. The bast fibers are mainly composed of cellulose, which potentially considers the growing techniques, harvesting and extraction processes of bast fibers most used to produce fibers with appropriate quality to apply in the daily lives of modern men and women in contemporary society. This review paper looks at many aspects of natural fibers, with a focus on plant bast fibers, including their impact on prehistoric and historical society. This review shows that bast fibers are competitive compared to man-made fibers in many applications, but variability in mechanical properties and low tenacity may limit their use in high-strengthh composites and extend to, particularly in aerospace, automotive, packaging, building industries, insulation, E-composites (Eco composites), geotextiles and many other applications are currently being explored. Considering, important characteristics of bast fibers include physical, mechanical, and chemical properties. This makes bast fibers one of the most important classes of plant fibers to use as reinforcing agents in thermosetting/thermoplastic polymer matrices. And the effect of bast fibers as reinforcement in the properties of ECO-composites, GREEN-composites, BIO-composites, lightweight composites. Bast fibers play an important role in sustainability, the preservation of the health of the environment, the well-being of the next generation, and even the daily lives of men and women in the contemporary world.
- Published
- 2024
- Full Text
- View/download PDF
5. Study of Cement-Based Mortars Reinforced with Guaruman Fibers in the Fresh State
- Author
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Lima, T. E. S., Oliveira, L. B., Candido, V. S., Silva, A. C. R., Marvila, M. T., Monteiro, S. N., Azevedo, A. R. G., Zhang, Mingming, editor, Peng, Zhiwei, editor, Li, Bowen, editor, Monteiro, Sergio Neves, editor, Soman, Rajiv, editor, Hwang, Jiann-Yang, editor, Kalay, Yunus Eren, editor, Escobedo-Diaz, Juan P., editor, Carpenter, John S., editor, Brown, Andrew D., editor, and Ikhmayies, Shadia, editor
- Published
- 2023
- Full Text
- View/download PDF
6. Seramik Sağlık Gereci Fabrikası Filtre-pres Kek Atığının Porselen Karo Bünyesinde Kullanılması.
- Author
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Karaca, Yusuf, Öztürk, Zahide Bayer, and Ubay, Elif
- Subjects
ENVIRONMENTAL responsibility ,WASTE products ,RAW materials ,WASTE recycling ,PORCELAIN ,MICROSTRUCTURE - Abstract
Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
- Full Text
- View/download PDF
7. Analytical Hierarchical Process as a Multicriteria Decision Tool in Material Selection for Prefabricated Wood Buildings
- Author
-
Matheus R. Cabral and Pierre Blanchet
- Subjects
AHP ,construction ,multicriteria ,technical properties ,social benefits ,Building construction ,TH1-9745 - Abstract
The popularity of prefabricated wooden buildings is increasing in North America, but choosing suitable materials for these structures can be complicated. This can lead to problems like financial losses, production delays, and lower quality. Therefore, the main goal of this study was to use the Analytical Hierarchy Process (AHP) decision-making tool to rank the criteria for material selection for prefabricated wood buildings in Canada and the United States. The methodology involved surveys experts in the prefabricated wood construction industry from Canada and the United States. The data obtained from the questionnaires utilized for the AHP analysis were modeled using R programming language. The results revealed that for structural materials, the top five subcriteria were safety and security of building occupants (0.234), location, shape, and height of the building (0.218), comfort, satisfaction, and well-being of the building (0.155), occupant health (0.121), and availability of materials (0.098). For selecting envelope materials, the top five subcriteria were comfort, satisfaction, and well-being of the building (0.252), safety and security of building occupants (0.206), location, shape, and height of the building (0.178), occupant health (0.132), and availability of materials (0.078).
- Published
- 2023
- Full Text
- View/download PDF
8. Influence of Stone Cutting Waste Addition on Technological Properties of Ceramic Sanitaryware Bodies.
- Author
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Zahide Bayer Ozturk, Kunduracı, Nazim, and Binal, Gulfem
- Subjects
- *
KAOLIN , *SLIP casting , *QUARTZ crystals , *CERAMIC materials , *INDUSTRIAL wastes , *SCANNING electron microscopes - Abstract
Usage of industrial wastes for the production of ceramic material is a crucial issue for preventing environmental pollution, reducing the utilization of natural raw materials, and abatement of production costs. In this study, the possibility of using the cutting waste of Nevsehir stones (Turkey) to make ceramic sanitaryware was explored. The compositions were prepared by partially replacing the clay and kaolin in the standard recipe with waste. The samples were shaped via the slip casting method and then fired in an industrial kiln. The fired samples were investigated for the firing shrinkage, water absorption, and deformation. The crystal phases and microstructure of the samples were identified by X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The results highlighted that the new sanitaryware samples with waste showed relatively higher water absorption and shrinkage values compared with the standard sample but they were still within the production standard limit. Amorphous behavior, quartz, and mullite phases were detected in all fired samples. SEM results of observed bodies show that the distribution of mullite and quartz crystals is homogenous. This study showed that cutting waste of Nevsehir stones can be a potential secondary raw material for the production of sanitaryware. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
9. Development of restoration mortars and artificial stones for use in restoring cultural heritage sites made from volcanic tuffs.
- Author
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Menningen, Johanna, Klein, Calvin, Pötzl, Christopher, Gross, Christian J., and Siegesmund, Siegfried
- Subjects
MORTAR ,STONE ,HISTORIC sites ,CULTURAL property ,CONSTRUCTION materials ,POROSITY - Abstract
Many historically significant buildings and cultural heritage sites are made of volcanic tuffs. These sites are subject to a progressive weathering and are partly in ruinous conditions. Preparing a suitable stone replacement mortar for repair work or even whole replacement stones for these rocks is of great interest. During the quarrying of tuff rocks, more than 40% of the material is rejected and cannot be further used. Utilizing this material, the production of replacement materials with optimized properties for the restoration and repair of severely damaged natural stones represents a resource-saving measure for the preservation of these buildings. In addition to the effective use of the natural stone waste, these artificial materials, in contrast to the very heterogeneous tuffs, offer a constant quality and consistent properties. A more effective exploitation can lead to a more sustainable usage of this natural resource and minimize the interference to the environment. This study describes the development of stone replacement mortars and the creation of artificial replacement stones utilizing source material from Mexico and Armenia. The resulting replacement material shows similar properties, aesthetics, and weathering behavior like the original rock, while different properties could be optimized. Petrophysical properties as well as the weathering behavior of the volcanic tuff rock were analyzed along with the developed replacement mortar and artificial stone. As hydric and thermohydric expansion processes are important factors for the durability of the investigated rocks, replacement materials were developed and optimized which, except for the pore structure of the cement and concrete matrix, show a high correspondence to the natural stones in terms of macroscopic appearance and technical properties. The compatibility of the replacement material with the original rock was investigated. Moreover, based on the evaluation of the mechanical as well as the pore space, water transport and weathering properties, the replacement stones were evaluated as equally suitable construction material, while the replacement mortars vary in regard to their results. Accordingly, the replacement stones developed in this study can be considered as full-fledged rock substitutes for the Armenian tuffs, while the replacement mortars for the Mexican tuffs partly show a good suitability and could be partially optimized. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
10. Natural Cellulosic Fiber from Coccinia Indica Stem for Polymer Composites: Extraction and Characterization
- Author
-
Mylsamy Bhuvaneshwaran, Sampath Pavayee Subramani, Sathish Kumar Palaniappan, Samir Kumar Pal, and Sethuraman Balu
- Subjects
coccinia indica fiber ,technical properties ,morphology ,reinforcement ,conventional fibers ,medicinal plant ,Science ,Textile bleaching, dyeing, printing, etc. ,TP890-933 - Abstract
This study mainly focuses on the possibility of using Coccinia Indica (CI) fiber as reinforcement in structural polymer composite materials because of its lightweight and eco-friendly nature. Fibers were extracted from the dried stems by combing process using metal teeth brush. The thermo-physico-mechanical properties, chemical compositions, and morphological structures of CI fiber were analyzed in detail. A higher percentage of cellulose content in CI fiber and the lesser amount of skimpy lignin, hemicellulose, ash, and wax content were confirmed through chemical analysis. The functional groups with their corresponding peaks were depicted through FTIR analysis. XRD studies divulge that the CI fiber contains crystallinity index (CrI) of 53.03% and crystallite size (L) of 5.81 nm. SEM revealed that the fiber possesses cylindrical morphology with multi-cellular structure. The presence of parenchyma and chlorenchyma tissues in the cell wall of CI fiber was also confirmed, which helps for better adhesion and mechanical properties to the composite. TGA study reveals that the major degradation of CI fiber occurs at a temperature range of 204.16°C to 376.3°C. The tensile strength of cellulose-based CI fiber is comparable with the other conventional fibers and it is well enough for its usage as reinforcing material in composite manufacturing.
- Published
- 2021
- Full Text
- View/download PDF
11. Guaruman fiber: A promising reinforcement for cement-based mortars
- Author
-
Afonso R.G. Azevedo, Thuany E.S. Lima, Raphael H.M. Reis, Michelle S. Oliveira, Verônica S. Candido, and Sergio N. Monteiro
- Subjects
Guaruman fiber ,Amazon lignocellulosic fiber ,Mortar ,Technical properties ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Guaruman fiber is a natural lignocellulosic fiber (NFL) extracted from the stalk of an Amazon plant (Ishinosiphon Koern), in the northern region of Brazil. The present work investigates the addition of 2.5, 5.0 and 7.5 wt% of guaruman fiber, into cement for a reference mortar. The fibers were mercerized in NaOH solution for improved adhesion to a mortar matrix made with 1:1:6 ratio of ordinary Portland cement, lime and natural sand. Technical properties of mass density, consistency, incorporated air content and water retention were for the first time evaluated for the as-processed fresh state of the mortar reinforced with this NFL. All methodologies used were adapted to the Brazilian technical standards. Relevant data were obtained from the international literature on the subject. It was found that the addition of NaOH-treated guaruman fiber practically does not affect the workability properties of the mortar. The results showed that the fiber surface treatment process promoted a mass density increase of ≈ 3% in the fresh state for the mortar with 7.5% of guaruman fibers. Meanwhile, this same trend was observed in water retention, which for the 7.5% mortar changed from 92.7%, with its fibers in the natural condition, to 94.24% in the treated condition. The incorporated air content increased in relation to the reference mixture, reducing comparatively in the treated conditions. These preliminary results in association with the relatively low mass density of the mortars incorporated with NaOH-treated guaruman fibers reveal a promising material to be applied as mortar for wall covering in civil construction, in a proportion of 7.5 wt%, which shows a great potential for the use of this fiber.
- Published
- 2022
- Full Text
- View/download PDF
12. Comparative analysis of selected features of traditional and photocatalytical paving stones
- Author
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Konrad Podawca and Agata Grzymała
- Subjects
technical properties ,traditional and photocatalytical paving stones ,cement tiocem® ,smog ,Environmental technology. Sanitary engineering ,TD1-1066 ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Nature friendly technologies in today’s world are the subject of scientific research and the interest of local authorities and the residents themselves. In the context of the city, one of the most important issues is the neutralization of air pollution generated by transport and heating of the premises with the use of solid fuels. The article analyses differences of the response of traditional and photocatalytic paving stones. We analysed water absorption, frost resistance, tensile strength at splitting and abrasion of paving stones. It has been proved that paving stones exposed to atmospheric factors and pollution during one heating season met the assumed quality criteria. In addition, the results obtained for the characteristics analysed were higher than the results of samples tested in laboratory conditions. The results also indicate a slight advantage of photocatalytic cubes in terms of their resistance to abrasion and tensile strength at splitting. Traditional and photocatalytic paving stones withstand well the operating conditions. It seems that products based on TioCem® cement are the future implementation of pedestrian and traffic routes.
- Published
- 2021
- Full Text
- View/download PDF
13. Fortification of durum wheat fresh pasta with red chicory by-product powder: Effects on technological, nutritional, and sensory properties.
- Author
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Bianchi, Federico, Santoro, Valentina, Pasqualoni, Ilaria, Bruttomesso, Margherita, Rizzi, Corrado, Piccinelli, Anna Lisa, and Simonato, Barbara
- Subjects
- *
RADICCHIO , *PASTA , *DURUM wheat , *FORTIFICATION , *HYDROXYCINNAMIC acids , *POWDERS - Abstract
The fortification of staple foods and the exploitation of agri-food by-products are the goals of modern food technologies. In this study, we prepared fortified pasta by replacing semolina flour with 5%, 10%, and 15% dried red chicory by-product powder (RCP), rich in fiber (27%) and healthy bioactive compounds (4.3%). The UHPLC-DAD-HRMS indicated hydroxycinnamic acids (HA), flavonoids (F), anthocyanins (A), and sesquiterpene lactones (SL) as the main bioactive compounds of RCP. The extraction recoveries of phenolic-fortified pasta (ranging from 0.2 to 13% for HAs to 5–28% for Fs and < 0.2% for As) suggest a high affinity with the semolina components, likely gluten or starch. The addition of RCP influenced (p < 0.05) the pasta's technological properties by inducing an increase in cooking loss, fully cooked time, and a decrease in the swelling index. The texture analysis showed that firmness and adhesiveness increased in the fortified sample. The sensory characterization showed a greater perception of vegetable and bitter flavor with increasing fortification levels. The RC15 sample had optimal technological, nutritional, and sensory characteristics. In conclusion, RCP could be an ingredient used to produce pasta with high fiber and bioactive compounds. • Red Chicory by-product powder is a source of bioactive compounds. • Phenolic compounds of red chicory byproducts were detected by UHPLC-DAD-HRMS. • Pasta fortification with red chicory byproduct powder was developed and analyzed. • Red chicory-fortified pasta has a higher content of polyphenols and fiber. • Red chicory by-product is a valuable functional ingredient for pasta formulation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. Evaluation of the technical properties of reactive-MgO cements produced by solar calcination of magnesite in a fluidized bed reactor.
- Author
-
Telesca, Antonio, Ibris, Neluta, Marroccoli, Milena, Tregambi, Claudio, Solimene, Roberto, Di Lauro, Francesca, Ruiz de Ballesteros, Odda, Salatino, Piero, and Montagnaro, Fabio
- Subjects
- *
FLUIDIZED bed reactors , *PORTLAND cement , *ATMOSPHERIC carbon dioxide , *MAGNESITE , *CEMENT , *FLUIDIZED-bed combustion , *SOLAR energy - Abstract
Magnesium oxide (MgO)-based cements display very interesting technical properties and environmentally-friendly features. The novel idea investigated in this study is to synthesize MgO cements, using as raw material natural magnesite calcined in fluidized bed heated by concentrated solar energy. Calcination was performed in a lab-scale system equipped with a concentrated solar simulator, operated under different process conditions. The most reactive MgO was mixed with 3% by weight of MgCO 3 (nucleation agent) and four different solutions containing magnesium acetate or chloride. The binders were hydrated in air or 20% CO 2 atmosphere (accelerated carbonation conditions) until 28 days. X-ray diffraction, differential-thermal and mercury intrusion porosimetry analyses, and compressive mechanical strength tests, were performed on the hydrated systems. Solar calcination produced a highly reactive MgO. The performance of the cement pastes improved at higher curing times, and when using magnesium acetate as hydration agent, as also witnessed by the application of a kinetic model. Accelerated carbonation conditions further enhanced the mechanical properties of the cements thanks to the formation of nesquehonite, allowing to reach a mechanical strength comparable to that of ordinary Portland cements class 32.5. The achieved outcomes encourage the production of low-CO 2 magnesite cements from solar calcined magnesite, boosting the green aspect of the entire process. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
15. Investigation on application progress of nano colloidal silica dioxide in fresh concrete.
- Author
-
U. Li, TANG Ji-yao, and YANG Da-tian
- Abstract
The development of nano-colloid silica for modified cement-based materials is studied. The research of nano-modified cement-based materials mainly focuses on the preparation of nano-modified cement-based materials, nano-modification mechanism and properties of modified cement-based materials. According to the existing research data of nano-colloid Silica modified cement concrete'the nano-colloid silica has the characteristics of small particle size,large specific surface area,and high activity. This paper reviews the current research status of nano-colloid silica modified cement concrete, combines its preparation process and its advantages and disadvantages, and analyzes the influence of the nano-material on the workability, mechanical properties, deformation performance' frost resistance and sliding resistance of cement concrete laws, discuss the modification mechanism of nano colloidal silica, to provide a basis for further application in cement concrete. [ABSTRACT FROM AUTHOR]
- Published
- 2022
16. Natural Cellulosic Fiber from Coccinia Indica Stem for Polymer Composites: Extraction and Characterization.
- Author
-
Bhuvaneshwaran, Mylsamy, Subramani, Sampath Pavayee, Palaniappan, Sathish Kumar, Pal, Samir Kumar, and Balu, Sethuraman
- Subjects
- *
NATURAL fibers , *COMPOSITE material manufacturing , *CELLULOSE fibers , *LIGNIN structure , *COMPOSITE materials , *LIGNANS , *LIGHTWEIGHT materials - Abstract
This study mainly focuses on the possibility of using Coccinia Indica (CI) fiber as reinforcement in structural polymer composite materials because of its lightweight and eco-friendly nature. Fibers were extracted from the dried stems by combing process using metal teeth brush. The thermo-physico-mechanical properties, chemical compositions, and morphological structures of CI fiber were analyzed in detail. A higher percentage of cellulose content in CI fiber and the lesser amount of skimpy lignin, hemicellulose, ash, and wax content were confirmed through chemical analysis. The functional groups with their corresponding peaks were depicted through FTIR analysis. XRD studies divulge that the CI fiber contains crystallinity index (CrI) of 53.03% and crystallite size (L) of 5.81 nm. SEM revealed that the fiber possesses cylindrical morphology with multi-cellular structure. The presence of parenchyma and chlorenchyma tissues in the cell wall of CI fiber was also confirmed, which helps for better adhesion and mechanical properties to the composite. TGA study reveals that the major degradation of CI fiber occurs at a temperature range of 204.16°C to 376.3°C. The tensile strength of cellulose-based CI fiber is comparable with the other conventional fibers and it is well enough for its usage as reinforcing material in composite manufacturing. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
17. Effect of Calcite Addition on Technical Properties and Reduction of Formaldehyde Emissions of Medium Density Fiberboard.
- Author
-
Camlibel, Osman
- Subjects
- *
MEDIUM density fiberboard , *CALCITE , *FORMALDEHYDE , *FLEXURAL strength , *MODULUS of elasticity , *AMMONIUM sulfate , *VAPOR pressure - Abstract
Physical, mechanical, and formaldehyde emission properties were studied for medium density fiberboard (MDF) produced with oak (75%) and pine (25%) fibers that had been mechanically refined in the presence of calcite particles. The calcite slurry was prepared at two levels of solids, 1.5% and 3% (10 and 20 kg·m-3). Chips were cooked for 4 min at 185 °C, under 8 bar vapor pressure in an Andritz defibrillator. 1.8% liquid paraffin, 0.72% ammonium sulphate solution, and 11% urea-formaldehyde were added by percentage based on oven-dried wood fibers in the blowline at the exit of the defibrator. The fibers were dried to 11% moisture content. MDF boards (2100 mm × 2800 mm × 18 mm) were created using a continuous hotpress process. The addition of calcite in the course of MDF production resulted in improved physical properties, such as thickness swelling (ThS 24 hours) and water absorption (WA 24 hours). MDF boards prepared with calcite exhibited higher internal bond (IB), modulus of rupture (MOR), and modulus of elasticity (MOE). Resistance to axial withdrawal of screw also was increased by addition of 3% calcite. In addition, the lowest levels of formaldehyde emission were observed for MDF prepared with calcite at the 3% level. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
18. Comparative analysis of selected features of traditional and photocatalytical paving stones.
- Author
-
PODAWCA, Konrad and GRZYMAŁA, Agata
- Subjects
PHOTOCATALYSIS ,COMPARATIVE studies ,NEUTRALIZATION (Chemistry) ,ABRASION resistance ,TENSILE strength - Abstract
Nature friendly technologies in today's world are the subject of scientific research and the interest of local authorities and the residents themselves. In the context of the city, one of the most important issues is the neutralization of air pollution generated by transport and heating of the premises with the use of solid fuels. The article analyses differences of the response of traditional and photocatalytic paving stones. We analysed water absorption, frost resistance, tensile strength at splitting and abrasion of paving stones. It has been proved that paving stones exposed to atmospheric factors and pollution during one heating season met the assumed quality criteria. In addition, the results obtained for the characteristics analysed were higher than the results of samples tested in laboratory conditions. The results also indicate a slight advantage of photocatalytic cubes in terms of their resistance to abrasion and tensile strength at splitting. Traditional and photocatalytic paving stones withstand well the operating conditions. It seems that products based on TioCem® cement are the future implementation of pedestrian and traffic routes. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
19. Era of bast fibers-based polymer composites for replacement of man-made fibers.
- Author
-
Santos CM, Santos TF, Aquino MS, Mavinkere Rangappa S, Siengchin S, and Suyambulingam I
- Abstract
Bast fibers are defined as those obtained from the outer cell layers of the bast of various plant families. They are finding use in textile applications and are widely used as reinforcements for green composites, as bast fibers are perceived as "sustainable". There is a growing demand for bast fibers across the world due to their renewable and biodegradable nature. The bast fibers are mainly composed of cellulose, which potentially considers the growing techniques, harvesting and extraction processes of bast fibers most used to produce fibers with appropriate quality to apply in the daily lives of modern men and women in contemporary society. This review paper looks at many aspects of natural fibers, with a focus on plant bast fibers, including their impact on prehistoric and historical society. This review shows that bast fibers are competitive compared to man-made fibers in many applications, but variability in mechanical properties and low tenacity may limit their use in high-strengthh composites and extend to, particularly in aerospace, automotive, packaging, building industries, insulation, E-composites (Eco composites), geotextiles and many other applications are currently being explored. Considering, important characteristics of bast fibers include physical, mechanical, and chemical properties. This makes bast fibers one of the most important classes of plant fibers to use as reinforcing agents in thermosetting/thermoplastic polymer matrices. And the effect of bast fibers as reinforcement in the properties of ECO-composites, GREEN-composites, BIO-composites, lightweight composites. Bast fibers play an important role in sustainability, the preservation of the health of the environment, the well-being of the next generation, and even the daily lives of men and women in the contemporary world., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
20. Egyptian Cretaceous clay deposits: Insights on Mineralogy, Geochemistry, and Industrial uses.
- Author
-
Farouk, Sherif, El-Desoky, Hatem, Heikal, Mohamed, El-Mahallawy, Medhat, and Wahid, Ahmed
- Abstract
Development of products which can be produced from a country's natural resources is very important as far as the industrialization of a nation and saving foreign exchange is concerned. The recent vast expansion of the ceramic industry in Egypt results in an excessively high consumption rate of Aswan clays, so the current study aims to explore other potential materials for application in the vitrified clay pipes industry. Based on the abundance of ceramic raw materials in Egypt and the demand for vitrified clay pipes, it is pertinent to develop and manufacture vitrified clay pipes by exploiting the locally available raw materials in other localities. This research thus concerns the characterization of some clay materials of the Cretaceous. Three economic clay formations were selected for the study: (1) the Malha Formation at Abu Darag and Zafarana, North Eastern Desert; (2) Naqb El Sillim Formation at the Bahariya Oasis, North Western Desert; and (3) Abu Aggag Formation at Aswan, South Eastern Desert. The clayey formations were investigated to assess their potential in the manufacture of vitrified clay pipes. Based on the obtained results of mechanical, chemical, and technical characteristics, the Naqb El Sillim Formation has the best results in a wide range of firing temperatures (1140–1180 °C) compared with the required limits of the international standards for clay pipes application. On the other hand, the Malha and Abu Aggag formations needed some additives to satisfy the standard limits of clay pipes application so, the granite wastes were selected and added by 20% to these samples, then fired at 1180 °C. The experimental results obtained from the studied samples indeed revealed the viability of manufacturing vitrified clay pipes from the raw materials. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
21. Porosity Structure and Technical Properties of Clinker Materials based on Non-Ferrous Metallurgy waste in Eastern Kazakhstan.
- Author
-
Kairakbaev, A. K., Abdrakhimov, V. Z., and Abdrakhimova, E. S.
- Subjects
- *
METALLURGY , *MECHANICAL properties of condensed matter , *METAL wastes , *POROSITY , *FELDSPAR , *ORES - Abstract
Clinker materials were obtained from non-ferrous metal waste, where the clay part of the gravity tailings of zircon-ilmenite ores (GZI) was used as the clay material and a byproduct of rare-earth metals without the use of natural conventional materials was used as the flux—feldspar concentrate (FSC). The studies showed that the content of dangerous pores with sizes 10–5 – 10–7 m in GZI samples is equal to 74%. The introduction of FSC (feldspar concentrate) into the ceramic bodies decreases the content of dangerous pores with sizes 10–5 – 10–7 m to 51%. Moreover, the introduction of FSC into the composition of the ceramic bodies significantly changes the distribution of micropores, and for samples with feldspar concentrate are characterized by a maximum of 32% in the pore size range 10–6 – 10–7 m, which attests a more uniform pore distribution. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
22. Investigation of the technical and physical properties of metal composite 1x1 rib knitted fabrics.
- Author
-
İLKAN, ÖZKAN
- Subjects
METALLIC composites ,KNIT goods ,METAL fibers ,ELECTROMAGNETIC shielding ,INVESTIGATIONS ,FILLER metal - Abstract
Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2020
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23. Stinging Nettles as Potential Food Additive: Effect of Drying Processes on Quality Characteristics of Leaf Powders
- Author
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Swathi Sirisha Nallan Chakravartula, Roberto Moscetti, Barbara Farinon, Vittorio Vinciguerra, Nicolò Merendino, Giacomo Bedini, Lilia Neri, Paola Pittia, and Riccardo Massantini
- Subjects
Urtica dioica L. ,drying ,powder ,technical properties ,functional properties ,Chemical technology ,TP1-1185 - Abstract
Stinging nettle (Urtica dioica L.) is a ubiquitous, multi-utility, and under-utilized crop with potential health benefits owing to its nutritional and bioactive components. The objective of the work is to produce powders by drying wild stinging nettle leaves as a storable, low-cost functional additive to be used in bakery and ready-to-cook products. Convective drying (CD) and freeze-drying (FD) were applied on unblanched (U) or blanched (B) leaves, which were then milled to nettle powders (NPs). The obtained NPs were evaluated for selected physicochemical (moisture, color), techno-functional (flow indices, hygroscopicity), and phytochemical (pigments, phenols) characteristics as well as mineral contents. Blanching improved mass transfer and reduced the oxidative degradation of pigments during drying, but it caused a loss of total phenols content, antioxidant activity, and potassium content. As for the drying method, CD resulted in better flow properties (i.e., Carr Index and Hausner Ratio), while FD retained better the color, pigments, magnesium content, phenolic, and antioxidant parameters. Overall, the evaluated processing methods resulted in different technological properties that can allow for better evaluation of NPs as a food additive or ingredient. Among the NPs, blanched and freeze-dried powders despite showing inferior technological properties can be recommended as more suitable ingredients targeted f or food enrichment owing to better retention of bio-active components.
- Published
- 2021
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24. Bast fibres: structure, processing, properties, and applications.
- Author
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Sadrmanesh, Vahid and Chen, Ying
- Subjects
- *
NATURAL fibers , *INVERSE gas chromatography , *FIBERS , *ATOMIC force microscopy , *SURFACE energy , *FREE surfaces - Abstract
There is an increasing demand for natural fibres worldwide due to their renewable and biodegradable nature. This paper reviews many aspects of natural fibres, focusing on the bast fibres of plants including hemp, flax, kenaf, jute, and ramie. Important characteristics of these plant fibres include physical, mechanical, dielectric, degradation, hygroscopic, and surface properties. These properties are highly variable, depending on both the chemical composition of the fibre and the environmental conditions. Retting and mechanical are the two main fibre extraction methods. When executed properly, retting produces the highest purity fibre; however, it is time-consuming and generates large amounts of wastewater. In contrast, mechanical extraction is faster and more environmentally friendly but results in low-purity fibre. Despite the drawbacks of bast fibres (e.g. low thermal stability, low hygroscopicity, low surface energy), they have been successfully used in insulation, composite, and geotextiles and many further applications are currently being explored. Abbreviations: AFM: Atomic force microscopy; CSA: Cross-section area; ρ: Density; DTG: Derivative thermogravimetric; γsd: Dispersive (d) component of surface free energy; γsp: Polar (p) component of surface free energy ; EMC: Equilibrium moisture content ; FACF: Fibre area correction factor; f: Fibre fineness; IGC: Inverse gas chromatography; LCA: Life cycling assessment; LLG: Limited life geotextile; LDPE: Low-density polyethylene ; MFA: Microfibril angle; RTM: Resin transfer moulding; γs: Surface free energy; WA: Thermodynamic work of adhesion; TGA: Thermogravimetric [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
25. Sintering, crystallization and properties of 2(Mg1−xMnx)O·2Al2O3·5SiO2 ceramics.
- Author
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Sutormina, E.F., Isupova, L.A., Molina, I.Yu., and Rudina, N.A.
- Subjects
- *
CRYSTALLIZATION , *THERMAL analysis , *CORDIERITE , *PHASE transitions , *SINTERING , *CERAMIC materials - Abstract
Abstract Mn-substituted cordierites, 2(Mg 1−x Mn x)O·2Al 2 O 3 ·5SiO 2 (x = 0–1), were prepared from natural components (talc, clay, alumina) and MnO 2. Sintering behavior, phase transformation, and microstructural features of the samples were investigated using X-ray diffraction (XRD), differential thermal analysis (DTA), dilatometric measurements and scanning electron microscopy (SEM) with energy dispersive analysis (EDS). The results of DTA and XRD analysis indicate that MnO 2 is successively reduced to Mn 2 O 3 and MnO in the sintering process. Mn2+ ions incorporate into the crystal structure of α-cordierite substituting Mg2+ ions in octahedral sites and thus increasing the cordierite unit cell volume. Mn promotes the sintering process: the crystallization temperature, melting point, density and open porosity of Mn-substituted cordierites lowered, whereas the shrinkage and medium pore diameter enlarged with an increase in MnO 2 content in the mixture of raw materials. Surface enrichment with Mn with the formation of manganese oxide crystallites was found for the samples with high substitution degree. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
26. Recycling reuse of municipal sewage sludge in sustainable structural materials: Preparation, properties, crystallization and microstructure analyses.
- Author
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Yu, Laihao, Zhang, Yingyi, Zhang, Zhenghao, Mao, Haobo, Han, Hongsong, and Yang, Jialong
- Subjects
- *
BRICKS , *CONSTRUCTION materials , *SEWAGE sludge , *WASTE recycling , *SLUDGE management , *FERRIC oxide , *MICROSTRUCTURE - Abstract
• A lightweight high-strength brick is synthesized from municipal sewage sludge and kaolin. • The bricks show superior performance as sustainable structural materials. • The effect of sintering temperature on the technical properties of bricks is discussed. • The sintering mechanism is analyzed emphatically from both phase composition and structure. • This study promotes the conversion of municipal sewage sludge into high value-added products. As a common solid waste in daily life, the disposal of municipal sewage sludge has always been global hot issues concerned by the world environmentalists. The present study reported the fabrication of lightweight high-strength bricks as sustainable structural materials by using kaolin and recycled municipal sewage sludge waste, and systematically discussed the effect mechanism of sintering temperature on product technical properties from both phase composition and microstructure. It showed that after sintering at 1250–1400℃, the porosity, sintering shrinkage, bulk density, compressive and bending strength of lightweight high-strength bricks were 11.30–37.18%, 23.81–38.86%, 1.57–2.22 g/cm3, 35–105 MPa and 23–84 MPa, respectively. And the variation trend of sintering shrinkage, bulk density and mechanical strength was positively correlated with sintering temperature, but completely opposite to that of porosity. For the phase composition, the change of sintering temperature would not affect the crystallization phase types in bricks, which were all composed of aluminum iron phosphate (Al 0.67 Fe 0.33 PO 4), cristobalite (tetragonal SiO 2), hematite (Fe 2 O 3), sillimanite (Al 2 O 3 ·SiO 2) and mullite (3Al 2 O 3 ·2SiO 2). For the microstructure, the melting and consolidation degrees of bricks were higher as the sintering temperature rose, and the structure became more dense and compact under the action of liquid glass phase, leading to a remarkable improvement and optimization of technical properties. Besides, the developed lightweight high-strength bricks presented strong competitiveness in structural materials, advancing a win–win for environment and development. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
27. Using Augmented Reality Technology in Education.
- Author
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YILMAZ, Rabia Meryem and GÖKTAŞ, Yüksel
- Abstract
In this study, the literature is reviewed on using augmented reality (AR) in education. How AR is a technology, its history, display systems and AR softwares are examined. In addition, which AR used any educational field and its providing educational gains are determined. AR can be used in natural sciences, computer and information sciences, mathematics, engineering, humanities and education. AR has been also used in medical, physics, chemistry, biology, astrology and geometry education, museums, storytelling activities, teaching cultural knowledge, engineering and special education. Especially, AR has been used for phenomena impossible to see by naked eye, simulation of potentially dangerous situations, visualization of abstract concepts and complexity phenomena. AR provides edutainment, rich interaction, natural experience and it improves attention and motivation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
28. Laminated strand lumber (LSL) reinforced by GFRP; mechanical and physical properties.
- Author
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Moradpour, Payam, Pirayesh, Hamidreza, Gerami, Masood, and Rashidi Jouybari, Iman
- Subjects
- *
GLASS fibers , *MODULUS of elasticity measurement , *FLEXURAL strength testing , *SHEAR strength , *LUMBER - Abstract
The effect of glass fiber reinforced polymer (GFRP) on the technical properties of LSL made from poplar ( Populus deltoids L . ) employing pMDI and UF as binders was investigated. Technical properties such as modulus of rupture (MOR), Modulus of elasticity (MOE), shear strength (SS), compression strength parallel to the grains (CS //), impact strength (IS), water absorption (WA) and thickness swelling (TS) were determined. Results confirmed that resin type and GFRP have significant effects on the LSL properties. It was revealed that the most beneficial effect of GFRP is on MOR, MOE, IS, SS and CS respectively. The Highest properties were obtained by using pMDI as the resin and GFRP as the reinforcement, where properties such as MOR, MOE, IS, SS and CS were improved by 123, 114, 100, 94, and 90%, respectively, compared to control samples. Furthermore, GFRP incorporation led to alteration of fracture place from tension side to compression side. Depending on the treatment type, the WA and TS values of the LVLs improved between 23% to 68% and 19.5% to 78%, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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29. Clayey wastes-based lightweight aggregates: Heating transformations and physical/mechanical properties.
- Author
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Loutou, M. and Hajjaji, M.
- Subjects
- *
CLAY wastes , *MINERAL aggregates , *CARBONATES , *KAOLINITE , *CALCIUM phosphate , *MULLITE - Abstract
Heating transformations of pellets of selected binary blends of raw clay, cement kiln dust and phosphate sludge were investigated by using different techniques (XRD, DSC, FT-IR and SEM), and their main technical properties were followed as a function of temperature. It was found that calc-aluminosilicate phase (gehlenite/labradorite) neoformed at T < 900 °C from the breakdowns of kaolinite and chlorite, and lime of decomposed carbonates. Moreover, fluorapatite (a component of phosphate waste-containing blends) gave rise to calcium phosphate (Ca 3 (PO 4 ) 2 ) and melt, which played a chief role in the sintering process of the pellets. The melt abundance induced the dissolution of mullite, which was the major constituent of the cement kiln dust. The results also showed that the compressive strength of the pellets increased and water absorption together with density (except for the phosphate waste-clay blend) decreased with increasing temperature. These evolutions were discussed in relation to the microstructure changes. The suitability of the blends in LWAs manufacturing was evaluated basing on the magnitudes of the measured properties. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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30. Lightweight and Durable PVDF–SSPF Composites for Photovoltaics Backsheet Applications: Thermal, Optical and Technical Properties
- Author
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M. H. Alaaeddin, S. M. Sapuan, M. Y. M. Zuhri, E. S. Zainudin, and Faris M. AL- Oqla
- Subjects
photovoltaic applications ,backsheets ,natural fiber composites ,optical properties ,thermal properties ,technical properties ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Photovoltaic module backsheets are characterized according to their thermal, optical, mechanical, and technical properties. This work introduces new fabricated backsheets for PV modules using polyvinylidene fluoride (PVDF) reinforced with short sugar palm fiber (SSPF) composites. The preparation of composites undergoes multiple phases of fabrication. Thermal, optical, and technical investigations of their properties were conducted. Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, in-situ scanning probe microscopy (SPM), dynamic mechanical analysis (DMA), thermal mechanical analysis (TMA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and prolonged technical testing were accomplished to expansively understand the complex behavior of composites under various conditions. The optical properties of PV backsheets are critical components in determining the reflectance, absorbance, and transmittance of light. The PVDF−SSPF composites exhibited exceptional compatibility and thermal stability, further revealing a homogenous composite structure with enhanced interfacial bonding between the short fiber and polymer matrix.
- Published
- 2019
- Full Text
- View/download PDF
31. Thermochemical Purification, Technical Properties, and Characterization of Ethiopian Diatomite from Adami-Tulu Deposit
- Author
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Weldemariam, Yonas, Enke, Dirk, Schneider, Denise, and Alemayehu, Esayas
- Published
- 2019
- Full Text
- View/download PDF
32. Clay bricks added with effluent sludge from paper industry: Technical, economical and environmental benefits.
- Author
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Vieira, Carlos Maurício F., Pinheiro, Regina M., Rodriguez, Ruben J. Sanchez, Candido, Veronica S., and Monteiro, Sergio N.
- Subjects
- *
PAPER industry & the environment , *CLAY minerals , *CONSTRUCTION materials , *SEWAGE , *RAW materials , *FABRICATION (Manufacturing) - Abstract
Recently, it was indicated that a feasible industrial alternative to valorize the sludge obtained from the treatment of waste water effluent of paper fabrication in Europe is its use as raw material in the production of clay bricks. The present technical note is an open report, probably first in Americas, on a Brazilian industrial-scaled solution for this kind of sludge. As a novelty, the sludge was added to a mixture of clays for improved technical properties of construction bricks. Both bricks, added with 10 wt% of sludge and conventional pure clay bricks for comparison, were simultaneously fired at a relatively low temperature of 750 °C according to the ceramic fabrication procedure. The technical characterization was performed by linear shrinkage, water absorption and mechanical compression tests as per Brazilian standards. The brick consolidated structure was analyzed by optical microscopy. Environmental impact was evaluated by solution test and atmospheric emission by monitoring the release of SO 2 , NO x , TOC, CO and particulate material, according to Brazilian standards. The results showed that, owing to its composition and firing temperature, the addition of paper sludge into clay bricks contributes to a substantial reduction in price associated with a saving of 3% of fuel similar to that reported for Spanish kilns, during the industrial firing stage. The paper sludge added clay bricks attended the technical and environmental standards. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
33. Evolution des connaissances sur les fonctionnalités de la fraction protéose-peptone du lait : propriétés techno-fonctionnelles et biologiques (synthèse bibliographique)
- Author
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Karamoko, G., Anihouvi, P., and Blecker, C.
- Subjects
Proteose-peptones ,glycoproteins ,biological properties ,milk ,peptides ,technical properties ,Biotechnology ,TP248.13-248.65 ,Environmental sciences ,GE1-350 - Abstract
The development of knowledge regarding the characteristics of the proteose peptone fraction of milk: Techno-functional and biological properties. A review. The total proteose-peptone fraction (TPP) is defined as a heat-stable soluble fraction of milk, representing about 10% of the whey protein. TPP is divided into two classes according to its origin. The first class consists of proteolysis fragments of the β-casein from the N-terminal region. These are non-hydrophobic fractions, which are the highly soluble β-CN-5P (f1-105/107); β-CN-4P (f1-28) and β-CN-1P (f29-105/107) respectively called PP5 (14.3 kDa), PP8S (9.9 kDa), and PP8F (4 kDa). The second class includes the hydrophobic fractions of glycoproteins, whose major constituents are a glycoprotein LP28, the highly hydrophobic glycoprotein LP18 and a hydrophobic peptide with apparent Mr, respectively 28 kDa, 18 kDa and 11 kDa. TPP has numerous interesting characteristics such as techno-functional properties (emulsifying and foaming actions) and biological properties (lipolysis inhibition and antimicrobial activities), making TPP usable as a potential functional ingredient for industry. In addition, these functional properties are partly governed by the major components including glycoproteins, such as LP28, due to their hydrophobic nature.
- Published
- 2013
34. Optimisation des paramètres d'extraction à froid de l'huile d'Azadirachta indica A. Juss et effets sur quelques caractéristiques chimiques de l'huile extraite
- Author
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Nitièma-Yefanova, S., Son, G., Yé, S., Nébié, RHC., and Bonzi-Coulibaly, Y.
- Subjects
Azadirachta indica ,plant oils ,pressing ,pressure extraction ,chemical properties ,technical properties ,Biotechnology ,TP248.13-248.65 ,Environmental sciences ,GE1-350 - Abstract
Optimization of the parameters of cold extraction of the oil of Azadirachta indica A. Juss and effects on some chemical parameters of the extracted oil. Azadirachta indicaA.Juss (neem) is a tropical tree, popular for its multiple possible uses. The oil extracted from neem kernels is used in cosmetics, as medicines, as insecticides and for energy needs (biofuel). The oldest oil extraction method is cold pressing. However, the optimal parameters of extraction and the quality of extracted oil are poorly known. The purpose of this research was to identify the optimal extracting parameters of neem oil by cold pressing and to characterize the extracted oil. The results showed that at 25 °C, the optimum yield by pressing of whole kernels was obtained with a pressure of 30.4 MPa ± 4.1 and a maximum degree of filling of the pressing cage. We showed that maintaining this pressure for 6 min could lead to an extraction rate of 40.1% ± 1.1. The oil yield increased with the speed of kernel compression. Reducing the particle size had a positive effect on oil yield when the cage load did not exceed half of the cage capacity. The best oil yield of 40.3% ± 0.0 for ground kernels was obtained with a pressure of 33.7 MPa ± 2.9 and a cage filled in the quarter of its capacity. The content levels of water, iron, copper and phosphorus in the oil extracted by pressing were respectively 0.14%; 11.8; 0.1 and 17 ppm. These characteristics indicate, inter alia, that neem oil obtained by cold pressing is of appropriate quality for use in biodiesel production.
- Published
- 2012
35. Impact of MDF Board Side Plane Instability on Lacquer Film Crack Appearance
- Author
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Vladimir Jambreković, Nikola Španić, Tajana Jambreković, and Borče Iliev
- Subjects
MDF board ,polyurethane film ,technical properties ,lacquer film cracks ,MDF board cracks ,Forestry ,SD1-669.5 - Abstract
This paper presents the research of a specific problem met in woodworking practice by the company K that manufactures door frames made of MDF boards (medium density fi breboards). Visible side surfaces of MDF door frames were lacquered with white polyurethane lacquer. Thirty days after installation, longitudinal surface cracks appeared in the lacquer fi lm on side planes of the door frame. Within the research of the said appearance of cracks, testing was carried out of technical properties and free formaldehyde concentration of the original door frame made of MDF boards by the manufacturer K, MDF boards of the same manufacturer from door frame plant, MDF boards made by the manufacturer H and lacquered experimental MDF boards of both manufacturers. The lacquered surface structure was tested by applying 97 % sulphuric acid (H2SO4) on 5 mm thick lattices that were cut out from side planes of experimental and original door frame samples. The action of acid destructed the lacquer final layer, and pigmented base with other additives was scraped off the surface. It was noticed that the lacquer film on the original door frame made of MDF panels by the manufacturer K had no two-component polyurethane clear base, or that it was applied in a very small quantity. Lacquer film cracking on side planes is the consequence of in-depth cracks in the structure of MDF panels that occur thirty days after lacquering. Experimental boards designated KE, produced by MDF manufacturer K, have an optimum layer of two-component polyurethane clear base, two-component polyurethane white base and two-component polyurethane semi gloss enamel paint. On side planes of these boards no distinctive cracks were observed. In lacquering MDF boards, it is necessary to apply two-component polyurethane clear base on side planes, and to fully protect the door frames with polyurethane films, and not only the visible planes. The use of load bearing MDF boards is necessary in dry conditions - MDF.LA type, and in increased relative humidity, fibreboards are required for general use in humid conditions - MDF.H type or load bearing boards for use in humid conditions - MDF.HLS type. Thin MDF board, glued to a thick MDF board, must be resistant to water or be an HDF fibreboard.
- Published
- 2011
36. Optimization of a Pressing Diagram in OSB Pressing
- Author
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Jaroslav Hrázský and Pavel Král
- Subjects
OSB ,pressing ,technical properties ,isocyanate glue (PMDI) ,urea-formaldehyd glue (UF) ,Forestry ,SD1-669.5 - Abstract
This paper summarizes the results of a pressing diagram optimization based on changes in pressure, temperature and distance between frames of a continuous press during Oriented Strand Boards (OSB) pressing. Tests of selected mechanical properties were carried out on OSB/3 boards with a nominal thickness of 18 mm - a basic type with urea-formaldehyd (UF) glue in surface layers and isocyanate glue (PMDI) in the central layer and further an ECO type with PMDI glue in all layers produced by a prominent manufacturer of OSB boards in the Czech Republic. OSB/3 boards are intended for structural purposes for use in wet environments. Changes in the pressing diagram were carried out at the stage of “press opening”, which signifi cantly affects mechanical and physical properties of OSB boards. In order to be able to compare the effects of changes in the pressing curve, the same setting of production parameters was used with all tested boards. The results of laboratory tests were compared with the values given in the ČSN EN 300 Standard. Optimization of the pressing process ranks among the most effective measures to increase the quality of particle boards at zero or minimum costs. The control of production processes is increasingly perfect thanks to the development of electronics, control and computer technology. At present, not only in our country but also worldwide, marked development of wooden constructions occurs thanks to the development of new types of wood-based composite materials and to the development of technologies in building industry. OSB boards are an important representative of wood-based composite materials for wooden constructions. As compared to natural material, OSB boards show a homogenous structure not including natural defects typical of solid wood. From the point of view of physical and mechanical properties, OSB boards are of orthotropic character.
- Published
- 2011
37. Design tools for interdisciplinary translation of material experiences.
- Author
-
Wilkes, Sarah, Wongsriruksa, Supinya, Howes, Philip, Gamester, Richard, Witchel, Harry, Conreen, Martin, Laughlin, Zoe, and Miodownik, Mark
- Subjects
- *
MATERIALS scientists , *ISOMORPHISM (Mathematics) , *PHYSICS experiments , *PSYCHOPHYSICS , *QUANTITATIVE research - Abstract
Designers increasingly have the opportunity to influence the development of materials as they emerge from the laboratory. In order for this to be successful, designers need to be able to communicate effectively with materials scientists so that materials can be developed with desired functionalities and properties. This paper reviews evidence in favour of using isomorphic sets of material stimuli as tools to bridge the disciplinary gap between designers and materials scientists. We show how these isomorphic sets and their accompanying experiments can be used to translate between the two communities, and to systematically explore the relationship between the technical attributes of materials and subjective experiences of their sound, taste and feel. This paper also explores the limitations of psychophysical approaches and other quantitative techniques for elucidating material experience, and suggests new possibilities for interdisciplinary collaborations that draw on ethnographic approaches. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
38. Supplementing pine with European beech and poplar in oriented strand boards.
- Author
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Akrami, Ali, Frühwald, Arno, and Barbu, Marius C.
- Subjects
PINE ,EUROPEAN beech ,POPLARS ,ORIENTED strand board ,RAW materials - Abstract
The objective of the study was to compare the properties of oriented strand boards (OSBs) made from the following mixtures: European beech and poplar, beech and pine, poplar and pine and 100% pine (i.e. the conventional raw material for OSB in Europe). Panels with 50–50% of beech-poplar/beech-pine/poplar-pine at two density levels of 650 kg/m3and 720 kg/m3were made with 5% pMDI (poly methylene di-isocyanate) as binder at 180°C and 240s as press conditions. Results showed that panels comprising a mixture of European beech and poplar have higher mechanical properties compared to panels made with mixtures of pine-beech or pine-poplar. In addition, for all panels, when density is increased from 650 kg/m3to 720 kg/m3, mechanical properties increased. Internal bond values for all designs were in the same range, especially at higher density (720 kg/m3). The pure pine panels showed lower values between different designs. Thickness swelling, an important physical property of OSB, improved when face and core layers consisted of a mixture of beech and poplar strands. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
39. Stinging Nettles as Potential Food Additive: Effect of Drying Processes on Quality Characteristics of Leaf Powders
- Author
-
Lilia Neri, Barbara Farinon, Giacomo Bedini, Swathi Sirisha Nallan Chakravartula, Vittorio Vinciguerra, Roberto Moscetti, Paola Pittia, Nicolò Merendino, and Riccardo Massantini
- Subjects
Health (social science) ,food.ingredient ,030309 nutrition & dietetics ,Blanching ,Hausner ratio ,Urtica dioica L ,TP1-1185 ,Plant Science ,powder ,Health Professions (miscellaneous) ,Microbiology ,Article ,03 medical and health sciences ,Ingredient ,0404 agricultural biotechnology ,food ,Carr index ,Food science ,drying ,Urtica dioica ,technical properties ,0303 health sciences ,functional properties ,Moisture ,Chemistry ,Chemical technology ,Food additive ,04 agricultural and veterinary sciences ,040401 food science ,Phytochemical ,Food security, food quality and human health ,Processing, packaging and transportation ,Food Science - Abstract
Stinging nettle (Urtica dioica L.) is a ubiquitous, multi-utility, and under-utilized crop with potential health benefits owing to its nutritional and bioactive components. The objective of the work is to produce powders by drying wild stinging nettle leaves as a storable, low-cost functional additive to be used in bakery and ready-to-cook products. Convective drying (CD) and freeze-drying (FD) were applied on unblanched (U) or blanched (B) leaves, which were then milled to nettle powders (NPs). The obtained NPs were evaluated for selected physicochemical (moisture, color), techno-functional (flow indices, hygroscopicity), and phytochemical (pigments, phenols) characteristics as well as mineral contents. Blanching improved mass transfer and reduced the oxidative degradation of pigments during drying, but it caused a loss of total phenols content, antioxidant activity, and potassium content. As for the drying method, CD resulted in better flow properties (i.e., Carr Index and Hausner Ratio), while FD retained better the color, pigments, magnesium content, phenolic, and antioxidant parameters. Overall, the evaluated processing methods resulted in different technological properties that can allow for better evaluation of NPs as a food additive or ingredient. Among the NPs, blanched and freeze-dried powders despite showing inferior technological properties can be recommended as more suitable ingredients targeted f or food enrichment owing to better retention of bio-active components.
- Published
- 2021
40. Evaluation par l'analyse sensorielle des qualité organoleptiques d'anciennes variétes de pommes
- Author
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Lateur M., Planchon V., and Moons E.
- Subjects
apples ,quality ,organoleptic properties ,organoleptic analysis ,varieties ,harvesting date ,storage ,keeping quality ,analytical methods ,fruits ,plant products ,pome fruits ,taxa ,technical properties ,timing ,Biotechnology ,TP248.13-248.65 ,Environmental sciences ,GE1-350 - Abstract
Organoleptic properties of old apple cultivars evaluated by sensory analysis. In the framework of a research programme focused on the evaluation and the valorization of fruit tree genetic resources, the sensory analysis technique has been used in order to evaluate the organoleptic properties of six old apple cultivars which are on trial in Belgium and North of France. The aims were to define their optimal picking time and storage aptitude, therefore marketing advices could be given to growers. Methodological aspects have been investigated on different sensory analysis parameters adapted to fresh fruits e.g. panel selection and formation, choice of descriptors. Sensory analysis was applied just after picking and periodically during the storage period. For each fruit sample, different characteristics were measured (brix, pH and flesh firmness) with the objective to calculate the correlation between sensory analysis data and analytical data. The results show that for the Jonagold cv., there is a very high correlation between ""crunchiness"", ""flesh firmness"" and ""juiciness"" sensory evaluated data. Other results, based on the experimentation of the six old cvs, confirm the correlation between the sensory analysis of the ""flesh firmness"" and the ""juiciness"", they show that the ""flesh firmness"" can be well assessed by a sensory analysis panel, and that the global fruit quality appreciation depends mostly on ""juiciness"", ""flesh firmness"" and sweet sensation. The sensory analysis can give good indication for a better commercial management of apple cvs concerning picking date, storage capacity and the best storage conditions to be chosen.
- Published
- 2001
41. Decay of calcareous building stone under the combined action of thermoclastism and cryoclastism: A laboratory simulation.
- Author
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Germinario, Luigi, Andriani, Gioacchino Francesco, and Laviano, Rocco
- Subjects
- *
POROUS materials , *MECHANICAL behavior of materials , *CALIBRATION , *HYGROMETRY , *SIMULATION methods & models - Abstract
This paper aims at illustrating the driving forces of thermoclastism and cryoclastism in calcareous building stone and their effects on fabric and technical properties. An artificial accelerated ageing test was carried out on a soft and porous calcarenite, which is exploited in Apulia (southern Italy) and historically used in the local architecture and manufacture as building and carving stone. The ageing was calibrated over the typical climatic characteristics of the region, attempting to simulate seasonal climatic changes. In details, quarry samples were subjected to temperature cycles from 60 to −5 °C, in a climatic chamber with a maximum relative humidity of 60%. During the test, the modifications in fabric were observed via SEM, whereas the changes in technical properties were analyzed through the direct or indirect measurement of: density, porosity, residual strains, p-wave velocity, compressive strength and Young’s modulus. The results give clues about the durability of soft calcareous stone opposed to thermo-hygrometric stresses and, indirectly, to natural weathering driven by climate variables. Moreover, a method is suggested for evaluating the resistance of stone to freezing–thawing decay, combining its porosimetric distribution with the environmental conditions of weathering. Finally, this paper globally adds new information about a material of significant cultural interest, which has been studied only recently in archaeometry. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
42. Thermal decay of carbonate dimension stones: fabric, physical and mechanical changes.
- Author
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Andriani, Gioacchino and Germinario, Luigi
- Subjects
EARTH sciences ,CARBONATE rocks ,THERMOCYCLING ,SEDIMENTARY rocks ,BUILDING stones - Abstract
This paper deals with the effects of thermal stresses on selected carbonate rocks used as dimension stones. They are Mesozoic calcareous and dolomitic rocks cropping out in Apulia (southern Italy) that, for their physico-mechanical and aesthetic properties, have always been finding a large application both as ornamental stones and as simple construction materials; their use is attested not only in Italy, in works of archaeological, historical and artistic interest too. The cause-effect relationships of thermal degradation were studied by means of an artificial accelerated ageing test, in order to provide a perspective about the decay of carbonate stones due to diurnal and seasonal temperature fluctuations, as well as thermal shocks during events of fire development. The stone samples were subjected to thermal cycles in a muffle furnace, ranging from 100 to 700 °C; after each cycle, several non-destructive and semi-destructive tests were carried out: mass and volume measurements, mercury intrusion porosimetry, sclerometer tests, ultrasonic tests, thin-section observations and determination of chromatic alterations through image analysis and Munsell charts method. In this way, the qualitative and quantitative modifications induced in fabric, physical and mechanical properties were discussed. The results highlight the fundamental role of depositional and diagenetic fabric that, together with mineralogical composition, represents the most significant discriminating factor in the response of the stone to thermal stresses. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
43. Scientific and technical aspects of blended cement matrices containing activated slate wastes.
- Author
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Frías, M., Vigil de la Villa, R., García, R., de Soto, I., Medina, C., and Sánchez de Rojas, M.I.
- Subjects
- *
SLATE , *CONSTRUCTION materials , *LANDFILLS , *POZZOLANIC reaction , *CHLORITES (Chlorine compounds) , *SMECTITE - Abstract
The extraction of slate for use as a construction material generates large quantities of waste (between 75% and 90% in weight), which are dumped on landfill sites, with the ensuing technical, economic, environmental, and social problems. One possible way of reusing this raw waste is through its thermal activation to produce a new cementitious material for the manufacture of eco-efficient cements. An assessment is presented in this study of the chemical, mineralogical and pozzolanic properties of ash waste, activated at 1000°C over 2h, as well as a study of the main technical properties of blended cements prepared with 10% and 20% slate ash. The results show the high pozzolanic activity of the slate ash, principally over the seven first days, forming CSH gels as a principal hydrated phase of the pozzolanic reaction, followed by randomly interstratified chlorite/smectite phases and monosulfoaluminate [C3A·SO4Ca·12H2O]. These blended cements prepared with 10% and 20% activated slate waste comply with both the physical and the mechanical requirements of current European standards. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
44. Перспективы внедрения системы блокчейн в банковской системе
- Subjects
банковская система ,области применения ,application areas ,the digital information in the blockchain ,блокчейн ,the banking system ,technical properties ,технические свойства ,цифровая информация - Abstract
С момента широкого распространения Биткойн особое внимание ученых и специалистов по всему миру приковано к основному инновационному компоненту этой криптовалюты - технологии blockchain, суть которой упрощенно можно представить в хранении цифровой информации в общедоступной базе данных, взаимосвязанных блоках. В данной статье затронуты вопросы раскрытия сущности системы блокчейн, возможности ее применения, а также проблемы и перспективы принятия и реализации в банковской системе. Целью данной статьи является развитие теоретических представлений о перспективах внедрения системы блокчейн в банковской системе. Для достижения этой цели автором уточнено понятие «блокчейн», раскрыты технические свойства этой системы, ее преимущества и недостатки, представлены схематически перспективы внедрения блокчейн в банковской системе., Since the widespread adoption of Bitcoin, special attention of scientists and specialists around the world has been focused on the main innovative component of this cryptocurrency - blockchain technology, the essence of which can be simplified in storing digital information in a public database, interconnected blocks. This article addresses the issues of disclosure of the essence of the blockchain system, its possible application, as well as problems and prospects for adoption and implementation in the banking system. The purpose of this article is to develop theoretical ideas about the prospects for implementing the blockchain system in the banking system. To achieve this goal, the author clarified the concept of "blockchain", disclosed the technical properties of this system, its advantages and disadvantages, and presented schematically the prospects for implementing blockchain in the banking system., Экономика и предпринимательство, Выпуск 9 (122) 2020
- Published
- 2020
- Full Text
- View/download PDF
45. Technology of Composites Based on Kul'-Yurt-Tau Pyrophyllites.
- Author
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Bakunov, V., Murzakova, A., Shayakhmetov, U., Shayakhmetov, R., and Yakupova, L.
- Subjects
- *
COMPOSITE materials , *PHOSPHATES , *BINDING agents , *TEMPERATURE effect , *PYROPHYLLITE , *THERMAL stability , *THERMAL conductivity , *ROCKS - Abstract
The basic technical characteristics of composites based on pyrophyllite and raw rocks from the Kul'-Yurt-Tau deposit and using phosphate binders are determined. While these materials have satisfactory strength their thermal expansion and thermal conductivity are low while the frost resistance and thermal stability are high. Such materials can be recommended as refractories and building materials for use at temperatures to 1250 - 1350°C depending on the composition of the initial batch. The technology for obtaining these materials is described. Parts and refractory mixes have found applications at certain enterprises. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
46. The influence of thermal activation of art paper sludge on the technical properties of blended Portland cements
- Author
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Ferreiro, S., Frías, M., Vigil de la Villa, R., and Sánchez de Rojas, M.I.
- Subjects
- *
PORTLAND cement , *THERMAL analysis , *PAPER recycling , *POZZUOLANAS , *WATER , *MATERIALS compression testing , *PARTICLE size distribution - Abstract
Abstract: The influence of the thermal activation (600–750°C) of a clayey waste (art paper sludge, APS) and the replacement rate of cement by this pozzolan on technical parameters such as normal consistency water, setting time, soundness and compressive strength were investigated. Physical properties of raw materials such as particle size distribution and BET surface areas were also reported. The results have demonstrated that substitution of Portland cement CEM I 42.5 by activated art paper sludge (AAPS) increases normal consistency water and decreases the setting times and compressive strength of the blended cements, with increasing replacement rate, temperature and/or time of activation. However, if APS is properly activated at around 600–650°C for 2h, it is feasible to substitute a 10% of cement without adverse effects on technical properties, due to the pozzolanic activity of metakaolinite and set regulator features of calcite, the two major mineral phases present in AAPS. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
47. Main technical characteristics of rocks used in road construction in Serbia.
- Author
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Djokic, Olivera and Milicevic, Vladimir
- Subjects
- *
ROCKS , *ROAD construction , *HEAVY construction - Abstract
The rocks used in road construction in a country depend to a large extent on the geological history of that country. Serbia, as a part of the Balkan Peninsula, has a wide variety of rocks of different ages and technical characteristics, but traditionally only a small number of rock types are used in road construction. This Technical note presents the characteristics of these rock and rock aggregates following national (SRPS) standards. It highlights the need for new testing/codes which can be related to European Standards but also the need for a practical approach considering performance in situ as well as measured properties. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
48. Characterization and properties of blended cement matrices containing activated bamboo leaf wastes
- Author
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Frías, Moisés, Savastano, Holmer, Villar, Ernesto, Sánchez de Rojas, M. Isabel, and Santos, Sergio
- Subjects
- *
BAMBOO , *PLANT litter , *ASH (Combustion product) , *FOURIER transform infrared spectroscopy , *POZZUOLANAS , *X-ray diffraction - Abstract
Abstract: The worldwide production of bamboo generates large volumes of leaf wastes, which are deposited in landfills or burned in an uncontrolled manner, with negative effects in the environment. The ash obtained by calcining of the bamboo leaf waste, shows good qualities as supplementary cementing material for the production of blended cements. The current paper shows a detailed scientific study of a Brazilian bamboo leaf ash (BLA) calcined at 600°C in small scale condition, by using different techniques (XRF, XRD, SEM/EDX, FT–IR, TG/DTG) and technical study in order to analyse the behaviour of this ash in blended cements elaborated with 10% and 20% by mass of BLA. The results stated that this ash shows a very high pozzolanic activity, with a reaction rate constant K of the order of 10−1/h and type I CSH gel was the main hydrated phase obtained from pozzolanic reaction. The BLA blended cements (10% and 20%) complied with the physical and mechanical requirements of the existing European standards. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
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49. Effect of activated coal mining wastes on the properties of blended cement
- Author
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Frías, M., Sanchez de Rojas, M.I., García, R., Juan Valdés, A., and Medina, C.
- Subjects
- *
ACTIVATION (Chemistry) , *CEMENT , *COAL mine waste , *GROUNDWATER , *TEMPERATURE effect , *MORTAR , *MATERIALS compression testing - Abstract
Abstract: The large volumes of coal waste generated world-wide in mining operations are mostly deposited in refuse dumps, to the severe detriment of the surrounding groundwater and soil. After calcination under controlled conditions, this waste has been shown to exhibit high pozzolanicity, making it apt for use as an addition in the manufacture of blended cements. The present paper describes the first detailed study designed to evaluate the behavior of coal tailings from different sources. After activation at 650°C for 2h, this waste was used to manufacture blended cements containing 10 and 20wt.% of the addition. Inclusion of this pozzolan did not affect the initial setting time, although the compressive strength of the blended mortars declined, by 4.7–8.3% in the 10% and by 9.76–14.9% in the 20% material. Nonetheless, the activated carbon waste (ACW) blends complied with all the requirements for Type II/A cement in the existing European legislation. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
50. Utjecaj nestabilnosti bočnih stranica MDF ploča na pucanje lakiranih filmova.
- Author
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Jambreković, Vladimir, Španić, Nikola, Jambreković, Tajana, and Iliev, Borče
- Abstract
Copyright of Wood Industry / Drvna Industrija is the property of Drvna Industrija and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2011
- Full Text
- View/download PDF
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