The non-isothermal leaching kinetics of primary titanium-rich material by microwave heating was investigated,and the temperature-pressure curves of leaching system and microwave absorption characteristics of mixture s...The non-isothermal leaching kinetics of primary titanium-rich material by microwave heating was investigated,and the temperature-pressure curves of leaching system and microwave absorption characteristics of mixture solutions before and after leaching were measured.The research of non-isothermal kinetics was evaluated by the leaching rate of Fe and the total apparent velocity equation of the non-isothermal kinetics of leaching for primary titanium-rich material by microwave heating was obtained.It is shown from the temperature-pressure curves that the high temperature and high pressure of closed leaching system are favorable to the enhancement of the leaching rate of Fe.Microwave absorption characteristics of mixture solutions before and after leaching show that there are abrupt changes of microwave absorption characteristics for 15%HCl solution and the mixture solution after leaching by 20%HCl.展开更多
The heavyweight ultra-high performance concrete(HUHPC)was prepared with barite sand partially replaced by titanium-rich heavy slag sand(THS)at replacement proportion of 0%,30%,50%,70%and 100%in this work.The results s...The heavyweight ultra-high performance concrete(HUHPC)was prepared with barite sand partially replaced by titanium-rich heavy slag sand(THS)at replacement proportion of 0%,30%,50%,70%and 100%in this work.The results show that THS incorporation can effectively improve the mechanical properties and reduce the volume shrinkage of HUHPC.The HUHPC with 50%THS replacement reaches an apparent density of 2890 kg/m^(3)(for fresh HUHPC),28 d compressive strength of 129 MPa,28 d flexural strength of 23 MPa,28 d flexural toughness of 28.4,56 d volume shrinkage of 359×10^(-4) and,as expected,excellent durability.Microstructural investigation demonstrates that the internal curing of pre-wetted THS promotes the hydration of the surrounding cement paste thereby strengthening the interfacial transition zone,resulting in the“hard shell”formation around aggregate to“protect”the aggregate.Additionally,the“pin structure”significantly improves the cement paste-aggregate interfacial connection.The combination of“hard shell protection”and“pin structure”remarkably improve the mechanical properties of HUHPC produced with porous THS aggregate.展开更多
目的:探讨3D打印个性化钛网的引导骨再生(guided bone regeneration,GBR)术及富血小板纤维蛋白(platelet-rich fibrin,PRF)/Bio-Oss复合物修复牙槽骨缺损的应用。方法:纳入2021年3月至2024年2月于甘肃省中医院口腔颌面外科行GBR骨增量...目的:探讨3D打印个性化钛网的引导骨再生(guided bone regeneration,GBR)术及富血小板纤维蛋白(platelet-rich fibrin,PRF)/Bio-Oss复合物修复牙槽骨缺损的应用。方法:纳入2021年3月至2024年2月于甘肃省中医院口腔颌面外科行GBR骨增量手术的牙槽骨缺损患者68例,随机分为3D组(n=34)与传统组(n=34),3D组使用3D打印个性化钛网及PRF/BioOss复合物,传统组使用传统钛网及PRF/Bio-Oss复合物。对比2组术后2、4、6个月的牙槽骨增加高度、宽度、体积及并发症发生率。结果:3D组术后2、4、6个月的牙槽骨增加高度、宽度与传统组相比,但差异均无统计学意义(P>0.05)。3D组术后2个月、4个月的牙槽骨增加体积均高于传统组,但差异均无统计学意义(P>0.05),术后6个月时牙槽骨增加体积显著高于传统组(P<0.05)。3D组发生早期暴露、晚期暴露、总暴露、创口感染的比例均低于传统组,但差异均无统计学意义(P>0.05)。结论:3D打印个性化钛网及PRF/Bio-Oss复合物的GBR术修复牙槽骨缺损效果良好,术后6个月骨增加体积显著高于应用传统钛网的GBR术,且不影响其安全性,值得临床推广应用。展开更多
基金Project(2007CB613606)supported by the National Basic Research Program of China
文摘The non-isothermal leaching kinetics of primary titanium-rich material by microwave heating was investigated,and the temperature-pressure curves of leaching system and microwave absorption characteristics of mixture solutions before and after leaching were measured.The research of non-isothermal kinetics was evaluated by the leaching rate of Fe and the total apparent velocity equation of the non-isothermal kinetics of leaching for primary titanium-rich material by microwave heating was obtained.It is shown from the temperature-pressure curves that the high temperature and high pressure of closed leaching system are favorable to the enhancement of the leaching rate of Fe.Microwave absorption characteristics of mixture solutions before and after leaching show that there are abrupt changes of microwave absorption characteristics for 15%HCl solution and the mixture solution after leaching by 20%HCl.
基金Funded by National Natural Science Foundation of China(Nos.52008002,U2006224 and 51878003)Doctoral Scientific Research Startup Foundation of Anhui Jianzhu University(No.2019QDZ66)。
文摘The heavyweight ultra-high performance concrete(HUHPC)was prepared with barite sand partially replaced by titanium-rich heavy slag sand(THS)at replacement proportion of 0%,30%,50%,70%and 100%in this work.The results show that THS incorporation can effectively improve the mechanical properties and reduce the volume shrinkage of HUHPC.The HUHPC with 50%THS replacement reaches an apparent density of 2890 kg/m^(3)(for fresh HUHPC),28 d compressive strength of 129 MPa,28 d flexural strength of 23 MPa,28 d flexural toughness of 28.4,56 d volume shrinkage of 359×10^(-4) and,as expected,excellent durability.Microstructural investigation demonstrates that the internal curing of pre-wetted THS promotes the hydration of the surrounding cement paste thereby strengthening the interfacial transition zone,resulting in the“hard shell”formation around aggregate to“protect”the aggregate.Additionally,the“pin structure”significantly improves the cement paste-aggregate interfacial connection.The combination of“hard shell protection”and“pin structure”remarkably improve the mechanical properties of HUHPC produced with porous THS aggregate.
文摘目的:探讨3D打印个性化钛网的引导骨再生(guided bone regeneration,GBR)术及富血小板纤维蛋白(platelet-rich fibrin,PRF)/Bio-Oss复合物修复牙槽骨缺损的应用。方法:纳入2021年3月至2024年2月于甘肃省中医院口腔颌面外科行GBR骨增量手术的牙槽骨缺损患者68例,随机分为3D组(n=34)与传统组(n=34),3D组使用3D打印个性化钛网及PRF/BioOss复合物,传统组使用传统钛网及PRF/Bio-Oss复合物。对比2组术后2、4、6个月的牙槽骨增加高度、宽度、体积及并发症发生率。结果:3D组术后2、4、6个月的牙槽骨增加高度、宽度与传统组相比,但差异均无统计学意义(P>0.05)。3D组术后2个月、4个月的牙槽骨增加体积均高于传统组,但差异均无统计学意义(P>0.05),术后6个月时牙槽骨增加体积显著高于传统组(P<0.05)。3D组发生早期暴露、晚期暴露、总暴露、创口感染的比例均低于传统组,但差异均无统计学意义(P>0.05)。结论:3D打印个性化钛网及PRF/Bio-Oss复合物的GBR术修复牙槽骨缺损效果良好,术后6个月骨增加体积显著高于应用传统钛网的GBR术,且不影响其安全性,值得临床推广应用。
