Synergistic Effect Of Silicon Research Articles

A novel co-continuous Si–Zr hybrid phenolic aerogel composite with excellent antioxidant ablation enabled by sea-island-like ceramic structure at high temperature

Lightweight phenolic matrix composites are highly potential in ablative thermal protective materials for future aerospace vehicles, and hybrid modification is considered as one of effective ways to improve the oxidation and ablation resistance of phenolic matrix. Herein, the co-continuous silica zirconium hybrid phenolic resin (SZRx) was synthesized, which can be used to prepare lightweight ablation resistant aerogel composites by the sol-gel method. The SZRx aerogel showed stable porous structure and excellent hydrophobicity, and the silicon zirconium hybrid greatly improved the high temperature carbon residue and oxidation resistance of phenolic resin. The SZRx aerogel composites also possessed excellent integrated characteristics of heat protection and insulation, with a linear ablation rate as low as 0.032 mm/s and a back temperature below 200 °C. The synergistic effect of silicon and zirconium formed the multiphase ceramic layer (C, SiO2, SiC and ZrO2) with the sea-island-like structure on the surface of the composite material, which can effectively resist high-temperature ablation and aerodynamic exfoliation. This can indicate that silicon zirconium dual element hybrid phenolic resin is the highly competitive matrix for lightweight and ablation resistant composite materials.

Synergistic effect of silicon and arbuscular mycorrhizal fungi reduces cadmium accumulation by regulating hormonal transduction and lignin accumulation in maize

Cadmium (Cd) stress causes serious damage to plants, inducing various physiological and biochemical disruptions that lead to reduced plant biomass and compromised growth. The study investigated the combined effects of silicon (Si) and arbuscular mycorrhizal fungi (AMF) on mitigating Cd stress in plants, revealing promising results in enhancing plant tolerance to Cd toxicity. Under Cd stress, plant biomass was significantly reduced (−33% and −30% shoot and root dry weights) as compared to control. However, Si and AMF application ameliorated this effect, leading to increased shoot and root dry weights (+47% and +39%). Furthermore, Si and AMF demonstrated their potential in reducing the relative Cd content (−43% and −36% in shoot and root) in plants and positively influencing plant colonization (+648%), providing eco-friendly and sustainable strategies to combat Cd toxicity in contaminated soils. Additionally, the combined treatment in the Cd-stressed conditions resulted in notable increases in saccharide compounds and hormone levels in both leaf and root tissues, further enhancing the plant's resilience to Cd-induced stress. Si and AMF also played a vital role in positively regulating key lignin biosynthesis genes and altering lignin-related metabolites, shedding light on their potential to fortify plants against Cd stress. These findings underscore the significance of Si and AMF as promising tools in addressing Cd toxicity and enhancing plant performance in Cd-contaminated environments.

Synergistic Effects of Silicon and Phosphorus Co-Application on Rice (Oryza sativa L.) Growth, Yield and Nutrient Use Efficiency in Saline Soil

Synergistic Effects of Silicon and Phosphorus Co-Application on Rice (Oryza sativa L.) Growth, Yield and Nutrient Use Efficiency in Saline Soil

Reducing Chromium Toxicity in Chinese Cabbage through Synergistic Effects of Silicon and Selenium: A Study of Plant Growth, Chromium Content, and Biochemical Parameters

Silicon (Si) and selenium (Se) have been found to reduce chromium (Cr) toxicity in plants, which is important for crop production and human health. However, there is limited understanding of the interaction between Si and Se in mitigating Cr toxicity and its mechanisms. This study investigated the impact of Si and Se on Cr-treated Chinese cabbage growth, Cr content, and biochemical parameters in a hydroponic experiment. The results showed that both Si and Se effectively alleviate Cr toxicity and have a strong synergistic effect. They reduced Cr content in cabbage by 73.99% and increased photosynthetic pigments by 62.50% and 47.51%, respectively. Antioxidant enzyme activity increased by 28.20 and 21.37%, while non-enzyme antioxidants such as proline and GSH decreased by 27.44 and 28.51%. It was observed that the addition of Si and Se to Chinese cabbage under Cr stress resulted in a 29.58 and 134.37% increase in soluble protein and soluble sugar, respectively, as well as improved nutrient contents (N, P, K, Ca, and Mg). This suggests that Si and Se can improve the physiological ecology of Chinese cabbage, reducing the effects of Cr stress and contributing to the global control of heavy metal pollution in food crops.

Synergistic Effects of Silicon and Preservative on Promoting Postharvest Performance of Cut Flowers of Peony (Paeonia lactiflora Pall.).

As a commercial high-grade cut flower, the marketability of herbaceous peony (Paeonia lactiflora Pall.) is limited by its short vase life in water. Si (silicon) is an alternative to improve the postharvest life of cut flowers. However, the effects of the combined application of Si and preservatives on the postharvest performance of cut peony flowers are unknown. In this study, the effects of a Si application and a preservative alone and collegial on the longevity of the vase life, water loss, antioxidant defense system, and stock carbohydrates level of cut flowers of three peony cultivars were investigated. It was observed that Si effectively prolonged the vase life, while the preservative alone, to a lesser extent, but markedly induced an early flowering and a greater flower diameter (flower open degree). The simultaneous use of Si and the preservatives not only showed larger flowers, but also improved the postharvest performance as characterized by an extended vase life and delayed the water loss. In addition, the Si supplementation dramatically intensified the antioxidant defense system (ameliorated antioxidant enzymes and alleviated ROS accumulation) in petals but did not increase the stock carbohydrates (starch and soluble sugars) levels, as compared to the treatment with the preservative alone. We show that a Si supplementation to a preservative is highly recommended for a large-scale use to promote the postharvest performance and competitiveness of marketed cut flowers.

The synergistic effects of silicon and selenium on enhancing salt tolerance of maize plants

Silicon (Si) and selenium (Se) have been recognized as beneficial elements for plant tolerance to abiotic stresses. However, the mechanisms responsible for the alleviating effects of Si-Se interactions on salt stress are still not clear. In this study, we compared the effects of Si and Se alone and in combination on the growth, sodium (Na) accumulation, photochemical parameters, the net Na+ flux and expression of salt resistance-related genes in maize plants under salt stress. The results showed that the addition of Si and Se significantly mitigated salt toxicity, and an obvious synergistic interaction was found between them. The application of Si and Se protected the structure and function of the photosynthetic apparatus from salt stress, and no differences were found between single and combined treatments. The combination of Si and Se significantly increased the net Na+ efflux and resulted in decreased Na+ influx in the root meristematic zone. Furthermore, salt stress-responsive genes, including ZmNHX and ZmSOS2, were upregulated under the combined treatment of Si and Se. These results indicate that the synergistic effects of Si and Se against salt stress were caused by the upregulated expression of transporter genes involved in Na+ uptake, exclusion and sequestration into vacuoles in roots.

Synergistic effect of silicon and selenium on the alleviation of cadmium toxicity in rice plants

Silicon (Si) and selenium (Se), two beneficial elements that alleviate cadmium (Cd) toxicity, are important for agricultural production and human health. However, the effects and related mechanisms of Si-Se interaction on Cd toxicity alleviation are still poorly understood. Herein, a hydroponic experiment was employed to evaluate the effects of Si and Se alone and together, on the growth, Cd content, and biochemical parameters of Cd-treated rice plants. The results revealed that both Si and Se can effectively alleviate Cd toxicity, and a strong synergistic effect of Si and Se was observed. Simultaneous use of Si and Se significantly promoted rice plant growth, decreased malondialdehyde (MDA) content in both the roots and shoots, and reduced Cd translocation factor leading to a significant 73.2 % decrease in shoot Cd content. Additionally, Si-Se interaction increased glutathione (GSH) content, phytochelatin (PC) content and Cd distribution in root cell walls and organelles. Furthermore, the relative expression of OsHMA2 was down-regulated, while those of OsNramp1 and OsMHA3 were up-regulated. The above findings suggest that synergistic effect of Si and Se on Cd toxicity amelioration occurs mainly via regulating gene expression, sequestering Cd in the root cell walls and organelles, and reducing Cd transfer to the shoots.

Reverse osmosis membrane autopsy in coal chemical wastewater treatment: Evidences of spatially heterogeneous fouling and organic-inorganic synergistic effect

Abstract Although fouling on reverse osmosis (RO) membrane has been studied widely, few focused on coal chemical industry where RO is indispensable for water reclamation. The complexity of the wastewater further makes the synergistic mechanism of inorganic and organic foulants unclear. Besides, spatial heterogeneity of fouling at different positions of RO module needs more investigation. This study analyzed samples from a two-stage RO module applied in a full-scale plant for coal chemical wastewater reclamation. Scanning electron microscope equipped with energy dispersive X-ray spectrometer (SEM-EDS), inductively coupled plasma optical emission spectrometer (ICP-OES), X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transformed infrared spectroscopy (ATR-FTIR), confocal laser scanning microscopy (CLSM), three-dimensional excitation-emission matrix (3D-EEM) and 16S sequencing were applied. Results showed that fouling gradually mitigated along the axial direction of the elements. Additionally, from stage-1 to stage-2, although organic fouling constantly dominated, inorganic fouling was aggravated while biofouling was alleviated with declined microbial diversity and population. The structure of microbial community also varied, which was due to the selectivity of higher salinity of the 2nd stage influent and interception of particular species in the 1st stage. Moreover, experimental evidences were provided for the bridging effect of Ca2+ and polysaccharides, as well as the synergistic effect of silicon and organic matters in fouling. The detailed foulant analysis on real membrane samples in this study may lay foundation for improving fouling control strategies in coal chemical industry.

Bone tissue engineering strategy based on the synergistic effects of silicon and strontium ions

Multipotent human bone marrow mesenchymal stem cells (hBMSCs) are commonly used as seed cells in bone tissue engineering, but their clinical application is limited due to two challenges. One is the expansion of hBMSCs without loss of the stemness, and the other is the stimulation of osteogenic differentiation of hBMSCs when combined with biomaterials. In this study we demonstrated an approach by firstly elucidating the functional effects and optimal concentrations of Si and Sr ions on the proliferation and osteogenic differentiation of hBMSCs, and then designing bioactive bioceramic/alginate hydrogels which could release Si and Sr bioactive ions in the same optimal concentrations range for activation of the cells in vivo. The results showed that Si and Sr ions could synergistically stimulate cell proliferation without losing the stemness. Furthermore, at higher concentrations, Si and Sr ions stimulated osteogenic differentiation instead of enhancing proliferation. The designed bioactive hydrogels revealed activity to stimulate not only the osteogenic differentiation of encapsulated hBMSCs, but also the blood vessel formation in vivo. These results suggested that the design of biomaterials based on the biological function of different material elements was an effective approach for bone tissue engineering applications. Statement of SignificanceThe clinical application of multipotent human bone marrow mesenchymal stem cells (hBMSCs) in bone tissue engineering is limited due to two challenges. One is the expansion of cells without loss of the stemness, and the other is the stimulation of osteogenic differentiation of hBMSCs within the biomaterial scaffolds. Herein, we demonstrated an approach by firstly elucidating the functional effects and optimal concentrations of Si and Sr ions on the proliferation without losing stemness and osteogenic differentiation of hBMSCs, and then designing a bioactive bioceramic/alginate hydrogel which could release Si and Sr ions for in vivo activation of cells. The bioactive hydrogels revealed activity to stimulate not only osteogenic differentiation of encapsulated hBMSCs, but also the blood vessel formation in vivo. Our work provided an effective approach to design effective biomaterials for tissue engineering.

Formation of icephobic film from POSS-containing fluorosilicone multi-block methacrylate copolymers

Abstract Polyhedral oligomeric silsesquioxane (POSS)-containing fluorosilicone multi-block methacrylate copolymers (PDMS- b -(PMAPOSS- b -PFMA) 2 ) were synthesized via RAFT polymerization of methacryloisobutyl POSS (MAPOSS) with hexafluorobutyl methacrylate (HFBMA) or dodecafluoroheptyl methacrylate (DFHMA) as different fluorinated side groups. A macro-RAFT chain transfer agent of polydimethylsiloxane with dithiobenzoate groups at both ends was initially used. Characterizations of surface chemical composition and morphology of the copolymer films suggested that the PDFHMA chains with longer fluorinated side groups, as compared with PHFBMA chains, were easy to migrate onto the surface and the surface roughness was enhanced by introducing PMAPOSS segments. The film of multi-block copolymer PDMS- b -(PMAPOSS- b -PDFHMA) 2 produced a fluorine-rich surface due to the enrichment of fluorinated blocks and exhibited the highest receding contact angle (103.8 ± 0.5°) and lowest water contact angle hysteresis (8.7 ± 1.4°) among all the samples, attributed to the introduction of PMAPOSS segments and the synergistic effect of silicon and fluorine. Measurements of icephobic properties demonstrated that the supercooled water droplet could easily slip away from the tilted PDMS- b -(PMAPOSS- b -PDFHMA) 2 surface (45°) at −20 °C and the ice shear strength tended to decrease from 361 kPa to 264 kPa with incorporation of PMAPOSS blocks in comparison with PDMS- b -(PFMA) 2 . However, it was found that decreasing wettability of the block copolymer film did not have significant effect on reducing the ice shear strength. The prepared POSS-containing fluorosilicone multi-block methacrylate copolymers with good icephobicity can be used as icephobic coating materials potentially.

Silicon as grain refiner in niobium microalloyed hot rolled steel

The effect of silicon on grain refinement has been investigated in industrially produced Nb microalloyed steel. The synergistic effect of silicon in the presence of Nb is found to favour grain refinement in hot rolled strip, which has resulted in very fine ferrite grains of <3; μm. Evolution of such a fine grain has been related to the enhanced precipitation of Nb(CN) in the presence of silicon. The concept of effective niobium (Nb + Si) in such steels has been introduced.

Erosion of ferritic FeCrC cast alloys at elevated temperatures

A series of experiments was carried out to quantify the wear properties for a wide range of ferritic FeCrC cast alloys at a temperature of 450°C. The main alloying elements of the alloys were varied as follows: 0.10%–2.48% C, 15%–43.8% Cr, 0.2%–0.51% Si. A semi-empirical model, based on Bitter's model of erosive wear, has been developed to describe the wear of these alloys as a function of chemical composition and wear conditions. It has been shown that, depending on wear conditions, carbon may be beneficial or deleterious. A synergistic effect of silicon with carbon has been observed, which would not have been obvious from simple wear analysis. Finally, the results clearly indicated that, from a wear resistance point of view, the chromium level is not important.

Synergistic Effects of Silicon and Phosphorus on Sintering of Ferrous Metal Powder Compacts

The sintering and alloying behaviour of ferrous metal powder compacts has been studied using dilatometry and scanning electron microscopy. Two binary compositions, Fe-3 wt % Si and Fe-3 wt% Fe3P (0.46 wt % P), and one ternary, Fe–3 wt % Si–3 wt % Fe3P were compared. In the ternary compacts it was found that phosphorus and silicon behaved synergistically. Phosphorus strongly enhanced the alloying which took place between iron and silicon at temperatures in the range 900–1100°C. Alloying with silicon, on the other hand, greatly enhanced the sintering (neck growth and shrinkage) or iron-phosphorus by rendering the alloy fully ferritic at all solid temperatures and thereby promoting higher rates of selfdiffusion in the alloy.

Synergistic Effects of Silicon and Phosphorus on Sintering of Ferrous Metal Powder Compacts

The sintering and alloying behaviour of ferrous metal powder compacts has been studied using dilatometry and scanning electron microscopy. Two binary compositions, Fe-3 wt % Si and Fe-3 wt% Fe3P (0.46 wt % P), and one ternary, Fe–3 wt % Si–3 wt % Fe3P were compared. In the ternary compacts it was found that phosphorus and silicon behaved synergistically. Phosphorus strongly enhanced the alloying which took place between iron and silicon at temperatures in the range 900–1100°C. Alloying with silicon, on the other hand, greatly enhanced the sintering (neck growth and shrinkage) or iron-phosphorus by rendering the alloy fully ferritic at all solid temperatures and thereby promoting higher rates of selfdiffusion in the alloy.