Why thermal stability is important in biopolymeric films?4 answersThermal stability is crucial in biopolymeric films due to its impact on the performance and applicability of these materials. Studies have shown that thermal stability plays a significant role in enhancing the resistance of biopolymers to high temperatures, which is essential in various applications such as oil and gas industry, medication administration, tissue engineering, and food packaging. Biopolymers like cellulose, starch, chitosan, and polylactic acid have been extensively studied for their weak thermal stability, highlighting the importance of improving this aspect for broader utilization. Blending biopolymers with other polymers, crosslinking agents, or nanofillers has been shown to enhance thermal stability, making them more suitable for diverse applications. Therefore, improving the thermal stability of biopolymeric films through various methods is crucial for expanding their functionality and ensuring their effectiveness in different industries.
How does silicon powder affect the compressive strength of concrete?5 answersSilica powder has a significant effect on the compressive strength of concrete. The addition of silica powder improves the compressive strength of concrete, as observed in various studies. In one study, the compressive strength of concrete increased by up to 18.8% when 5% of silica stone waste (SSW) powder was added. Another study found that the compressive strength of lightweight aggregate concrete increased by 14% and 33% when the silica content was increased to 10% and 15%, respectively. Additionally, the incorporation of high-silicon tailing powder in concrete enhanced its compressive strength, resulting in green high-performance concrete. Furthermore, the combination of silica fume (SF) and steel slag powder (SSP) showed a synergistic hydration effect, leading to improved compressive strength of concrete. Overall, the use of silica powder in concrete positively affects its compressive strength, making it a valuable additive for enhancing concrete performance.
How does the addition of silicon affect the microstructure of medium Mn steel?5 answersThe addition of silicon has been found to affect the microstructure of medium Mn steel. It has been observed that an increase in silicon content leads to an increase in hardness and mechanical strength of the steel. The presence of silicon also influences the morphology of retained austenite, with samples containing silicon exhibiting both polygonal and lath-like retained austenite, while samples without silicon only have polygonal retained austenite. Additionally, the microstructural characteristics of the steel, such as the presence of equiaxed dual phases or a bimodal-grained structure, can also be influenced by the addition of silicon, resulting in different mechanical properties and strain hardening abilities. The dissolution of silicon in the steel's phases, such as Nbss and silicide, also contributes to solid solution strengthening and improved fracture toughness.
Does silicon contribute to temperature tolerance by stabilizing membranes and regulating oxidative stress in plants?5 answersSilicon plays a role in temperature tolerance in plants by stabilizing membranes and regulating oxidative stress. Silicon application improves drought tolerance in lentil genotypes by maintaining nitro-oxidative homeostasis and antioxidant defense responses. It reduces membrane damage and increases the concentration of osmolytes, such as proline and glycine betaine, in drought-stressed lentil plants. Silicon also balances the concentrations of reactive oxygen/nitrogen species and increases the activities of antioxidant enzymes, such as ascorbate peroxidase, guaiacol peroxidase, and catalase, to protect cell membranes from oxidative damage. Additionally, silicon enhances the efficiency of the glutathione-ascorbate cycle and increases the concentrations of glutathione and ascorbate, further contributing to the antioxidant defense system. Overall, silicon contributes to temperature tolerance in plants by stabilizing membranes and regulating oxidative stress through various mechanisms.
What are the effects of Si on the membrane stability and thermal stress resistance?5 answersSi incorporation has various effects on membrane stability and thermal stress resistance. In the case of a membrane distributed-reflector (DR) laser, Si bonding technology using a chemical mechanical polishing (CMP) process and surface activated bonding (SAB) with an a-Si layer achieved room temperature bonding, resulting in a reduction in thermal resistance and improved thermal characteristics. Si doping in perovskite type oxides for oxygen transport membranes (OTM) also enhances stability by increasing the chemical stability of samples in reducing atmosphere. For nanocrystalline soft magnetic ribbons, Si substitution stabilizes the coercivity (Hc) after heat treatment, improving thermal stability. Additionally, Si incorporation in Al-Ti-N coating improves thermal stability and oxidation resistance, retarding the formation of w-AlN and promoting the formation of Al-oxide rich top-scale. Si incorporation in diamond-like carbon (DLC) films enhances thermal stability and reduces friction coefficient, possibly due to the formation of a SiO2 transfer film on the wear scar surface.
What is the function of silicon in plant cell walls?5 answersSilicon plays a crucial role in plant cell walls by improving their mechanical strength and resistance to biotic and abiotic stresses. It has been shown to participate in the process of biomineralization, where it forms amorphous silica on the root surface, altering the physical and chemical properties of the cell wall. Silicon accumulation in plant tissues provides increased resistance to mechanical stresses, reduced water loss through transpiration, increased resistance to sunlight, and reduced metal toxicity and salt stresses. Xyloglucan-bound silicon enhances the resistance to degradation by cellulase and improves the nanomechanical properties of the cell wall at the single-cell level. Silicon-rich materials can also reduce heavy metal toxicity in plants by transferring heavy metals to the cell walls and converting them into immobilized forms. Overall, silicon in plant cell walls contributes to their structural integrity and provides protection against various stresses.