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Mechanical, Thermal and Hydric Behavior of the Bio-sourced Compressed Earth Block (B-CEB) Added to Peanut Shells Powder
Nassio Sory,
Moussa Ouedraogo,
Adamah Messan,
Issiaka Sanou,
Moustapha Sawadogo,
Kouka Jeremy Ouedraogo,
Halidou Bamogo,
Ouanmini Bobet,
Lamine Zerbo,
Mohamed Seynou
Issue:
Volume 11, Issue 1, March 2022
Pages:
1-13
Received:
9 December 2021
Accepted:
24 December 2021
Published:
8 January 2022
Abstract: Bio-sourced compressed earth blocks (B-CEB) were manufactured with raw soil material and peanut shells powder to produce building material with feeble environmental impact and better mechanical and hydric performances. The objective of this work is to add value to two local natural raw materials namely earth and peanut shell in the production of B-CEB with low thermal conductivity, better water resistance, and better mechanical strength. Mineralogical studies (by XRD, DTA-TG), chemical and geotechnical studies (Atterberg limits, particle size distribution) carried out on this clay have shown that it is composed of kaolinite (40 wt.%), muscovite (8 wt.%), quartz (34 wt.%), and goethite (10 wt.%). It is a sandy-silty clay of medium plasticity containing no swelling minerals. Its particles are mainly clay (50 wt%), silt (32 wt%), fine and coarse sand (18 wt%). The clay raw material used in this study is referenced BAM. The peanut shells powder, used in range of 10 to 40 wt.% to improve the raw soil, mainly contains the cellulose type I. The apparent density of B-CEB decreases when the peanut shells content increases. By contrast, the porosity increases and was greatly affect by the addition of peanut shells powder. With 20 wt.% of peanut shells powder the porosity of B-CEB increase about 67% compared to the porosity of the reference (untreated B-CEB). Mechanical properties were enhanced with peanut shell content between 15 to 25 wt.% and reached the maximum with 20 wt.%. The B-CEB becomes more ductile when the peanut shells content increases. All the elaborated B-CEB, except the B40, are in the category of the construction of load-bearing wall which is characterized by the strength higher than 4 MPa. With 15 to 30 wt.% of peanut shells powder, the resistance of B-CEB to rain erosion was enhanced. With 30 wt.% of peanut shells powder, thermal conductivity was reduced by about 43% compared with untreated B-CEB. Given the improvement of different properties, the peanut shells powder can be used in the range of 15 to 25 wt.% to stabilize the B-CEB for the construction of habitats with better durability and thermal comfort.
Abstract: Bio-sourced compressed earth blocks (B-CEB) were manufactured with raw soil material and peanut shells powder to produce building material with feeble environmental impact and better mechanical and hydric performances. The objective of this work is to add value to two local natural raw materials namely earth and peanut shell in the production of B-...
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Research Progress of Composite Materials of NiTi SMA and Stainless Steel
Haoyuan Zeng,
Jianping Zhou,
Yan Zhang
Issue:
Volume 11, Issue 1, March 2022
Pages:
14-19
Received:
26 October 2021
Accepted:
11 November 2021
Published:
18 March 2022
Abstract: Nickel Titanium Shape Memory Alloys (NiTi SMA) are material with high strength and good biocompatibility, and more and more applications in several industrial domains, like aerospace, automotive, biomedical and power plants. However, there are still facing some restrictions for themself mechanical property and joining techniques. The composite structure of the NiTi SMA with the Stainless Steel (SS) could better play its characteristics and advantages, and has broad application prospects. Meanwhile, NiTi SMA and SS have great differences in physical and chemical properties. And it is easy to produce brittle metal compounds due to the difficulty of joint welding. Many scholars have studied the dissimilar connection between NiTi SMA and SS, and successfully prepared NiTi/SS orthodontic arch wire according to the research results, but there is still much room for development. This review aimed to provide a comprehensive overview of the recent progress in welding of NiTi SMA and SS, and to introduce current research and application. Lastly, the research status and existing problems of dissimilar metal welding between NiTi SMA and SS in recent years have been summarized. This review focused on the fundamental understanding of the microstructural characteristics, processing and property relationships in the welding and joining of heterogeneous joints.
Abstract: Nickel Titanium Shape Memory Alloys (NiTi SMA) are material with high strength and good biocompatibility, and more and more applications in several industrial domains, like aerospace, automotive, biomedical and power plants. However, there are still facing some restrictions for themself mechanical property and joining techniques. The composite stru...
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Studies on Synthesis and Electrochemical Properties of Lithium Ferrous Silicate Cathode Materials
Wang Qingsheng,
Pavel Novikov,
Anadoli Popovich,
Yang Zhelong,
Yu Yao,
Okonov Leonid
Issue:
Volume 11, Issue 1, March 2022
Pages:
20-29
Received:
15 December 2021
Accepted:
25 December 2021
Published:
23 March 2022
Abstract: The lithium ferrous silicate (Li2FeSiO4) has high theoretical capacity of 330 mAh/g, abundant raw material resources, stable working voltage, excellent thermal stability of Si-O bond, environmental protection and low cost, and has become one of the attractive cathode materials in high-energy lithium batteries. However, the conductivity of Li2FeSiO4 material itself is poor, and the ionic conductivity is low, so improving the conductivity and Li+ diffusion coefficient of the material has become the focus of research. In this paper, Li2FeSiO4 material was synthesized by the combination of sol-gel method and solid-state sintering method, and the nano-material and metal ion doping were realized by liquid-phase grinding method, which increased the specific surface area and conductivity of the material and increased the specific energy of the material. XRD, TGDSC, particle size analysis and electrochemical capacity test show that the specific capacity of the initial Li2FeSiO4 material synthesized in solid phase is 120 mAh/g, and the capacity of the nano-treated Li2FeSiO4 material reaches 140mah/g; The Li2Fe0.5Mn0.5SiO4 material obtained by Mn doping has a capacity of 160mah/g; The volume of Li2Fe0.5Mn0.45Ti0.05SiO4 synthesized by adding metal Ti is increased to 195mah/g; The electrical conductivity of Li2Fe0.5Mn0.5Si0.975V0.025O4+C synthesized by doping v and c can be significantly improved, and the discharge capacity can reach about 200mAh/g. In the liquid phase grinding of the mixture of ethanol and acetone, it was found that the tautomers of alcohol and ketone were in the dynamic equilibrium of ketone and enol, and acetone met positively charged metal ions to form stable metal salts, which improved the stability of the material.
Abstract: The lithium ferrous silicate (Li2FeSiO4) has high theoretical capacity of 330 mAh/g, abundant raw material resources, stable working voltage, excellent thermal stability of Si-O bond, environmental protection and low cost, and has become one of the attractive cathode materials in high-energy lithium batteries. However, the conductivity of Li2FeSiO4...
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