scholarly journals EFFECTS OF IMPREGNATION WITH STYRENE AND NANO-ZINC OXIDE ON FIRE-RETARDING, PHYSICAL, AND MECHANICAL PROPERTIES OF POPLAR WOOD

CERNE ◽  
2016 ◽  
Vol 22 (4) ◽  
pp. 465-474 ◽  
Author(s):  
Siroos Habibzade ◽  
Hamid R. Taghiyari ◽  
Asghar Omidvar ◽  
Hamid R. Roudi
Keyword(s):  
Mechanical Properties ◽  
Zinc Oxide ◽  
Zno Nanoparticles ◽  
Ignition Time ◽  
Physical And Mechanical Properties ◽  
Dry Weight ◽  
Poplar Wood ◽  
Nano Zinc Oxide ◽  
Wood Polymer ◽  
Nano Zinc

ABSTRACT Nanoparticles have been vastly applied in wood polymer composites (WPCs) in the recent years to improve some of the drawbacks of solid wood species. In the present study, the effects of ZnO nanoparticles on fire retarding, physical, and mechanical properties of polymerized poplar wood were investigated. Poplar specimens were impregnated with styrene monomer, containing four different contents of nano-zinc oxide (ZnO) (0, 0.5, 1 and 1.5%, based on the dry weight of monomer). Results of the scanning electron microscopy (SEM) showed homogeneous dispersion of ZnO nanoparticles in the WPC matrix. Nano-zinc oxide improved physical properties such as dimensional stability and water absorption. Moreover, mechanical properties increased in comparison to the control specimens. The impregnation process also significantly improved some of the fire-retarding properties, including the ignition time; however, the flammability nature of styrene aggravated some others, such as carbonized area. It was concluded that, although most of the properties were improved, the final application of WPC should be taken in to consideration before making decision on whether or not to impregnate populus wood with styrene.

scholarly journals The Root Endophytic Fungus Serendipita indica Decreased the Phytotoxicity of Zinc Oxide Nanoparticles to Alfalfa (Medicago sativa L.)

2021 ◽  
Author(s):  
Leila Tabande ◽  
Mozhgan Sepehri ◽  
Jafar Yasrebi ◽  
Mehdi Zarei ◽  
Reza Ghasemi-Fasaei ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Plant Growth ◽  
Zinc Oxide Nanoparticles ◽  
Sinorhizobium Meliloti ◽  
Dry Weight ◽  
Oxide Nanoparticles ◽  
Zno Nps ◽  
Shoot Dry Weight ◽  
Nano Zinc Oxide ◽  
Nano Zinc

Abstract Zinc oxide nanoparticles (ZnO-NPs) are among the most commonly used nano-fertilizers (NF). However, elevated levels of ZnO-NPs in soil may affect plant growth and development due to its potential toxicity when accumulated in large amounts in plant tissues. This research was conducted using an in situ rhizobox system with the aims of evaluating Zinc uptake from nano-zinc oxide amended rhizosphere soil by alfalfa plant and the effect of plant growth promoting microorganisms on alleviating the phytotoxicity of ZnO-NPs. Treatments included microbial inoculations (Sinorhizobium meliloti, Serendipita indica) and different ZnO-NPs concentrations (0, 400 and 800 mg Kg− 1) with three replications. The results indicated that S. indica minimized the phytotoxicity of ZnO-NPs to alfalfa by enhancing growth rate and decreasing Zinc (Zn) translocation from root to shoot. Compared with plants inoculated with S. meliloti, co-inoculation with S. indica increased the shoot dry weight by 18.33% and 8.05% at 400 and 800 mg Kg− 1ZnO-NPs. However, at the highest level of ZnO-NPs (800 mg kg− 1), root inoculation of S. indica and S. indica + S. meliloti decreased Zn transfer factor by 60.2% and 44.3% compared to S. meliloti, respectively. Furthermore, a distinct relation between tolerance of S. indica-colonized plant to ZnO-NPs and the ability of S. indica in inhibiting or retarding degradation of polyunsaturated lipids through prevention of excess reactive oxygen species formation was observed. Malondialdehyde content of inoculated plants with S. indica either alone or in combination with S. meliloti was significantly lower than non-inoculated plants (p < 0.01). Zn-induced oxidative stress was mitigated by S. indica through enhanced activities of catalase and peroxidase enzymes. The findings of the present study indicate the potential use of endophytes fungus S. indica for ensuring food safety and security, and human health in heavy metal–polluted soil by reducing the phytoavailability of heavy metals in the aerial parts of the host plants.

scholarly journals Zinc oxide nanoparticles alleviate the arsenic toxicity and decrease the accumulation of arsenic in rice (Oryza sativa L.)

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shiwei Yan ◽  
Fan Wu ◽  
Song Zhou ◽  
Jianhao Yang ◽  
Xianjin Tang ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Zinc Oxide Nanoparticles ◽  
Oryza Sativa L ◽  
Dry Weight ◽  
Oxide Nanoparticles ◽  
Rice Seedlings ◽  
Nano Zinc Oxide ◽  
Class 1 ◽  
Nano Zinc ◽  
Different Levels

Abstract Background Rice is particularly effective, compared to other cereals, at accumulating arsenic (As), a nonthreshold, class 1 human carcinogen in shoot and grain. Nano-zinc oxide is gradually used in agricultural production due to its adsorption capacity and as a nutrient element. An experiment was performed to explore the effects of zinc oxide nanoparticles (nZnO) on arsenic (As) toxicity and bioaccumulation in rice. Rice seedlings were treated with different levels of nZnO (0, 10, 20, 50, 100 mg/L) and As (0, and 2 mg/L) for 7 days. Results The research showed that 2 mg/L of As treatment represented a stress condition, which was evidenced by phenotypic images, seedling dry weight, chlorophyll, and antioxidant enzyme activity of rice shoot. The addition of nZnO (10–100 mg/L) enhanced the growth and photosynthesis of rice seedlings. As concentrations in the shoots and roots were decreased by a maximum of 40.7 and 31.6% compared to the control, respectively. Arsenite [As (III)] was the main species in both roots (98.5–99.5%) and shoots (95.0–99.6%) when exposed to different treatments. Phytochelatins (PCs) content up-regulated in the roots induced more As (III)-PC to be complexed and reduced As (III) mobility for transport to shoots by nZnO addition. Conclusion The results confirmed that nZnO could improve rice growth and decrease As accumulation in shoots, and it performs best at a concentration of 100 mg/L.

scholarly journals Zinc Oxide Nanoparticles Alleviate The Arsenic Toxicity and Decrease The Accumulation of Arsenic in Rice(Oryza Sativa L.)

2021 ◽  
Author(s):  
Shiwei Yan ◽  
Fan Wu ◽  
Song Zhou ◽  
Jianhao Yang ◽  
Xianjin Tang ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Zinc Oxide Nanoparticles ◽  
Oryza Sativa L ◽  
Dry Weight ◽  
Oxide Nanoparticles ◽  
Rice Seedlings ◽  
Nano Zinc Oxide ◽  
Class 1 ◽  
Nano Zinc ◽  
Different Levels

Abstract Background: Rice is particularly effective, compared to other cereals, at accumulating arsenic(As), a nonthreshold, class 1 human carcinogen in shoot and grain. Nano-zinc oxide is gradually used in agricultural production due to its adsorption capacity and as a nutrient element. An experiment was performed to explore the effects of zinc oxide nanoparticles (nZnO) on arsenic (As) toxicity and bioaccumulation in rice. Rice seedlings were treated with different levels of nZnO (0, 10, 20, 50, 100 mg/L) and As (0, and 2 mg/L) for seven days. Results:The research showed that 2 mg/L of As treatment represented a stress condition, which was evidenced by phenotypic images, seedling dry weight, chlorophyll, and antioxidant enzyme activity of rice shoot. The addition of nZnO (10-100 mg/L) enhanced the growth and photosynthesis of rice seedlings. As concentrations in the shoots and roots were decreased by a maximum of 40.7% and 31.6% compared to the control, respectively. Arsenite [As(III)] was the main species in both roots (98.5-99.5%) and shoots (95.0-99.6%) when exposed to different treatments. Phytochelatins (PCs) content up-regulated in the roots induced more As(III)-PC complexed and reduced As(III) mobility for transport to shoots by nZnO addition. Conclusion:The results confirmed that nZnO could improve rice growth and decrease As accumulation in shoots, and it performs best at a concentration of 100mg/L.

Preparation of nano-zinc oxide/EPDM composites with both good thermal conductivity and mechanical properties

2010 ◽  
Vol 119 (2) ◽  
pp. 1144-1155 ◽  
Author(s):  
Zhenhua Wang ◽  
Yonglai Lu ◽  
Jun Liu ◽  
Zhimin Dang ◽  
Liqun Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Zinc Oxide ◽  
Nano Zinc Oxide ◽  
Nano Zinc

scholarly journals Optimisation Of Nano-ZnO And Nano-SiO2 Mixing Time For Bitumen Modification

2021 ◽  
Vol 1202 (1) ◽  
pp. 012017
Author(s):  
Judita Gražulytė ◽  
Audrius Vaitkus ◽  
Simona Bitarytė
Keyword(s):  
Mechanical Properties ◽  
Mixing Time ◽  
Physical And Mechanical Properties ◽  
Modified Bitumen ◽  
Nano Zno ◽  
Nano Zinc Oxide ◽  
The Difference ◽  
Nano Zinc ◽  
Dispersion Of Nanoparticles ◽  
Bitumen Modification

Abstract Nanotechnologies have gradually penetrated to the field of bitumen modification especially where durable asphalt mixtures have to be designed. Longer mixing time, higher temperatures or/and higher rotation (shearing) speeds are needed to increase the dispersion of nanoparticles in bitumen. However, this is not necessarily beneficial to the physical and mechanical properties of the final material. As a result, in this study nano-zinc oxide (nano-ZnO) and nano-silica (nano-SiO2) mixing time for bitumen modification was optimized considering the physical and mechanical properties of the final bitumen. For this purpose bitumen PMB 25/55-60 was modified with nanoparticles at 180 °C using a laboratory high-shear mixer at a rotation speed of 4000 rpm for different modification time selected on the basis of literature review (60 and 90 minutes). Penetration, softening point, viscosity at 135 °C, recovery and non-recoverable creep compliance (multiple stress creep and recovery test) at 60 °C were measured in order to determine the optimal mixing time. The results showed that 60 minutes ensures the dispersion of nano-ZnO and nano-SiO2 in the bitumen PMB 25/55-60 and longer mixing time do not have a significant effect on the properties of nano-ZnO and nano-SiO2 modified bitumen (the difference was less than 7%).

Effect of Calcination on the Basic Strength of Surface Modified Nano-Zinc Oxide Characterised by FTIR and Back Titration Methods

2015 ◽  
Vol 1107 ◽  
pp. 326-332
Author(s):  
Abdul Rahim Yacob ◽  
Kamaluddeen Suleiman Kabo
Keyword(s):  
Zinc Oxide ◽  
Metal Oxides ◽  
Base Catalysis ◽  
Nano Zinc Oxide ◽  
Back Titration ◽  
And Performance ◽  
Nano Zinc ◽  
Surface Modified ◽  
Heterogeneous Base ◽  
Basic Strength

The use of metal oxides in heterogeneous base catalysis has gained a large interest due to their application in many chemical and industrial processes and is environmental friendly. Basic metal oxides are commonly used and their structures, morphology and performance can be modified by method of preparation and thermal activation. In this study, surface modified amphoteric zinc oxide was prepared via hydration-dehydration method and characterised by TGA and FTIR. The basic strength at various temperatures is characterised by FTIR and back titration analyses. The results shows that surface modified zinc oxide has the highest basic strength of 1.453mmolg-1at 400°C making it a relatively good and suitable compound for use in heterogeneous basic catalysis. This result is also supported by FTIR spectra which show possible relationship between the Lewis O2-and increasing basic strength.

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