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E-BABE——制造和表征壳聚糖/蒙脱土/氧化锆纳米复合材料支架

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生物高分子具有相同的特权作为天然的生物降解和类似的结构组织额外的细胞成分。壳聚糖作为一种功能材料适合生物医学应用由于其生物相容性等优良性能,抗原性,生物降解性,抗菌、凝血和高机械强度适合组织工程。通常结合粘土Na-montmorillonite等增强机械强度,良好的化学,壳聚糖的尺寸稳定性和硬度。在这项研究中,一个高度专业化的脚手架冷冻干燥方法组成的壳聚糖(CTS),蒙脱石(MMT)和nano-zirconia (nano-SRO2)准备。CTS / MMT /氧化锆蒙脱土纳米复合材料,由氧化锆和加强。SEM, XRD和红外光谱研究这些特点,表明纳米复合材料支架的形成。使用显示的热稳定性是TGA方法,所以,孔隙大小,因此CTS / MMT / SRO2的孔隙分布计算使用选择技术。蒙脱石也可能是轻微的层状硅酸盐的矿物质,可以溶解后形成成水溶性微粒称为粘土晶体。Montmorillon命名,法国。蒙脱石,蒙脱石集团的成员可能是2:1粘土,也就是说,一个中央八面体片氧化铝,两个四面体的二氧化硅三明治。 The particles are in the shape of a plate with a diameter around 0.9 nm and a thickness around 1 μm; To "see" individual clay particles, they need to be enlarged approximately 25,000 times with a microscope. Members of this group include saponite.Montmorillonite could even be a subclass of smectite, a 2: 1 phyllosilicate mineral characterized as having an octahedral charge greater than 50%; its cation exchange capacity is due to the isomorphic substitution of Mg for Al in the central plane of alumina. Substitution of lower valence cations in such cases leaves the oxygen atoms nearby with a net charge which can attract the cations. In contrast, beidellite is smectite with a tetrahedral charge greater than 50% from the isomorphic substitution of Al for Si in the silica sheet. The individual crystals of montmorillonite clay are not closely linked, so that water can intervene, causing the clay to swell. The water content of montmorillonite is variable and it increases considerably in volume when it absorbs water. Chemically, it is sodium silicate hydroxide-aluminum-magnesium hydrate (Na, Ca) 0.33 (Al, Mg) 2 (Si4O10) (OH) 2 · nH2O. Potassium, iron and other cations are common substitutes, so the precise ratio of cations varies depending on the source. It often occurs in admixture with chlorite, muscovite, illite, cookeite and kaolinite. Montmorillonite is used in the oil drilling industry as a lubricant component, which makes mud mud viscous, which helps keep the bit cool and removes drilled solids. it is also used as an additive to retain soil water in drought prone soils, used in the development of dams and earthen pits, and to prevent leakage of fluids. it is also used as a component of foundry sand and as a desiccant to induce humidity in air and gases. Montmorillonite clays are widely used in catalytic processes. Cracking catalysts have used montmorillonite clays for more than 60 years. Other acid-based catalysts use acid-treated montmorillonite clays. Montmorillonites are expanding considerably quite other clays because of water penetrating the interlayer molecular spaces and asaithe concurrent. the quantity of expansion is mainly due to the type of interchangeable cation in the sample. The presence of sodium because the clay swelling to its original volume may be repeatedly caused by the greatest interchangeable cation. Accordingly, sodium montmorillonite was used because it is the most important ingredient in non-component agents for splitting rock in natural stone quarries in an attempt to limit the amount of waste, or to demolish concrete structures where it is impossible to use removal of explosive charges. Because of this reconstructive property bentonite containing montmorillonite is also useful as a seal or annular additive for water wells and as a protective liner for landfills. Other uses include as an antidepressant agent in animal feed, in paper-making to reduce deposit formation, and as a maintenance and drainage assistance component. Montmorillonite was used in cosmetics. In fine powder form, it can also be used as a flocculant in ponds. It is thrown to the surface because it falls into the water, making the water "cloudy", attracts small particles within the water and settles on the lower one, cleansing the water. Koi and goldfish (carpet) then feed the "clump" which helps digest the fish. it is sold in pond supply stores. Sodium montmorillonite is also used due to the origin of some cat litter products, due to its adsorbent and clumping properties.

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