Creating mesopores in ZSM-48 zeolite by alkali treatment: Enhanced catalyst for hydroisomerization of hexadecane

ZSM-48 zeolites with various Si/Al ratios were hydrothermally synthesized in the H;N（CH;）;NH;（HDA）-containing media. The obtained samples were highly crystallized with minor mixed phases as evidenced by X-ray powder diffraction（XRD）. The alkaline treated ZSM-48 zeolites maintained its structure under different concentrations of Na OH aqueous solution. Micropores remained unchanged while mesopores with wide pore size distribution formed after the alkaline treatment. The surface area increased from 228 to 288 m;/g. The Br?nsted acid sites had little alteration while an obvious increase of Lewis acid sites was observed. The hydroisomerization of hexadecane was performed as the model reaction to test the effects of the alkali treatment. The conversion of hexadecane had almost no change, which was attributed to the preservation of the Br?nsted acid sites. While high selectivity to iso-hexadecane with an improved iso to normal ratio of alkanes was due to the mesopore formation and improved diffusivity.

超声引导下聚多卡醇泡沫硬化治疗肾囊肿的临床应用价值

目的探讨超声引导下聚多卡醇泡沫在肾囊肿硬化治疗中的临床应用价值。方法分析我院于2019年1月至2020年6月期间收治的42例肾囊肿患者,均在超声引导下行聚多卡醇泡沫硬化治疗,所有患者在术后1、3、6、12个月定期随访复查超声,根据囊肿的缩小率评价疗效。结果42例患者的42个肾囊肿,术后1、3、6、12个月随访,治愈率分别为11.9%、35.7%、42.9%、59.5%;总有效率分别为59.5%、83.3%、92.9%、100.0%。Cox多因素回归分析显示囊肿容积的大小为影响聚多卡醇治疗效果的主要因素。结论超声引导下聚多卡醇泡沫硬化治疗肾囊肿安全、有效,术后随访时间越长,治疗效果越显著,且囊肿容积越小,疗效越确切,值得在临床推广应用。