目的探究低温老化后立体光固化(stereolithography SLA)和数控切削减材制造(computer numerical control CNC)制作的氧化锆材料在微观结构、力学性能以及光学特性上的变化,为临床选择提供参考。方法根据材料及老化情况分为4组(n=6):SLA...目的探究低温老化后立体光固化(stereolithography SLA)和数控切削减材制造(computer numerical control CNC)制作的氧化锆材料在微观结构、力学性能以及光学特性上的变化,为临床选择提供参考。方法根据材料及老化情况分为4组(n=6):SLA未老化组(SLA-non-low-temperature degradation,SLA-NLTD)、SLA老化组(SLA-LTD)、CNC未老化组(CNC-NLTD)、CNC老化组(CNC-LTD)。使用立式高压蒸汽灭菌锅,在134℃、0.2 MPa条件下进行24 h低温老化处理。通过X射线衍射和扫描电镜观察相变与表面形貌;通过三点抗弯测试及维氏硬度检测进行力学性能评估;依据国际照明委员会(Commission Internationale de l'Éclairage,CIE)1976 L*a*b*色度体系,使用分光测色仪测量各组试件的CIE L*、a*、b*值,计算半透明参数和色差。结果X射线衍射显示,SLA-LTD组单斜相含量显著增加,扫描电镜观察到其表面晶粒隆起与微裂纹现象更为明显。SLA-LTD组抗弯强度低于SLA-NLTD组[(571.46±39.55)MPa vs(658.29±80.93)MPa,P<0.05];CNC-LTD组和CNC-NLTD组抗弯强度比较无显著差异(P>0.05)。SLA-LTD组维氏硬度显著低于SLA-NLTD组(P<0.05);CNC-LTD组维氏硬度低于CNC-NLTD组(P<0.05)。4组半透明参数由高到低为:CNC-NLTD组>CNC-LTD组>SLA-NLTD组>SLA-LTD组。SLA组色差为1.94±0.21,处于感知阈与可接受阈之间;CNC组色差为1.13±0.19,低于感知阈,临床上可视为无明显色差。结论CNC制备的氧化锆在力学、光学的稳定性上表现更佳;虽然SLA制备的氧化锆老化后力学性能、光学特性有所下降,但仍能满足临床使用要求。展开更多
The bovine hydroxyapatite(BHA) was applied to prepare biological tissue engineering scaffolds by the method of extrusion freeforming. To achieve this goal, BHA were added to sodium alginate(SA) solution to form a slur...The bovine hydroxyapatite(BHA) was applied to prepare biological tissue engineering scaffolds by the method of extrusion freeforming. To achieve this goal, BHA were added to sodium alginate(SA) solution to form a slurry system in appropriate proportion. The resulting mixtures were fabricated to be a kind of controllable and porous scaffolds followed with cross-linking in 5% calcium chloride(CaCl_2) solution for 24 h. After that, the scaffolds were sintered in air at 1 000, 1 100, 1 200 and 1 300 ℃ for 5 h. Scanning electron microscopy(SEM) and X-ray diffraction(XRD) studies were performed on the scaffolds to analyze its microstructure and constituent. To explore the effect of sintering temperature on scaffolds, the compressive strength, volume shrinkage and water absorptivity of BHA-SA composite scaffolds after sintering were investigated. The research tests indicated the feasibility of applying BHA powder to 3D printing. Besides, the scaffolds sintered in a respectively lower temperature possess much more pores and performed higher water absorptivity, which means better cellular affinity. And scaffolds sintered between 1 100 and 1 200℃ presents higher compressive strength.展开更多
In order to protect quality of Baiyangdian surface water and Gaoyang groundwater,the project is applied to process printing and dyeing wastewater that contains complicated compositions,high concentrations of organics ...In order to protect quality of Baiyangdian surface water and Gaoyang groundwater,the project is applied to process printing and dyeing wastewater that contains complicated compositions,high concentrations of organics and SS,and lots of pollutants difficult to degrade by microorganism. The process and operating parameters of project are optimized and debugged,and its economic and environmental benefits are analyzed.The results show that the process of coagulation sedimentation-hydrolytic acidification with aeration tank-biological aerated filter-active sand filter is applied in Gaoyang Sewage Treatment Plant. The design scale of sewage treatment plant is 120000 m^3/d. The influent is as following: COD is 669mg/L; SS is 424mg/L; NH_3-N is 8.83mg/L; TP is 6.03mg/L. After the process,the best removal rates of COD,SS,NH_3-N and TP are 93. 5%,98. 8%,97. 1% and 96. 2%,respectively. The various indexes of effluent water complied with standard A of the first order in Pollutants Emission Standard of Urban Wastewater Treatment Plant( GB 18918-2002). The processing cost is only 0. 807 yuan/m^3. As a result,the project construction and operation not only improve the environment,but also promote regional economic development. Process design and operating parameters provide an important reference value for the printing and dyeing wastewater treatment industry.展开更多
文摘目的探究低温老化后立体光固化(stereolithography SLA)和数控切削减材制造(computer numerical control CNC)制作的氧化锆材料在微观结构、力学性能以及光学特性上的变化,为临床选择提供参考。方法根据材料及老化情况分为4组(n=6):SLA未老化组(SLA-non-low-temperature degradation,SLA-NLTD)、SLA老化组(SLA-LTD)、CNC未老化组(CNC-NLTD)、CNC老化组(CNC-LTD)。使用立式高压蒸汽灭菌锅,在134℃、0.2 MPa条件下进行24 h低温老化处理。通过X射线衍射和扫描电镜观察相变与表面形貌;通过三点抗弯测试及维氏硬度检测进行力学性能评估;依据国际照明委员会(Commission Internationale de l'Éclairage,CIE)1976 L*a*b*色度体系,使用分光测色仪测量各组试件的CIE L*、a*、b*值,计算半透明参数和色差。结果X射线衍射显示,SLA-LTD组单斜相含量显著增加,扫描电镜观察到其表面晶粒隆起与微裂纹现象更为明显。SLA-LTD组抗弯强度低于SLA-NLTD组[(571.46±39.55)MPa vs(658.29±80.93)MPa,P<0.05];CNC-LTD组和CNC-NLTD组抗弯强度比较无显著差异(P>0.05)。SLA-LTD组维氏硬度显著低于SLA-NLTD组(P<0.05);CNC-LTD组维氏硬度低于CNC-NLTD组(P<0.05)。4组半透明参数由高到低为:CNC-NLTD组>CNC-LTD组>SLA-NLTD组>SLA-LTD组。SLA组色差为1.94±0.21,处于感知阈与可接受阈之间;CNC组色差为1.13±0.19,低于感知阈,临床上可视为无明显色差。结论CNC制备的氧化锆在力学、光学的稳定性上表现更佳;虽然SLA制备的氧化锆老化后力学性能、光学特性有所下降,但仍能满足临床使用要求。
基金Funded by the National Natural Science Foundation of China(Nos.81371939 and 31270150)Science and Technology Support Program of Jiangsu Province,China(No.BE2013057)
文摘The bovine hydroxyapatite(BHA) was applied to prepare biological tissue engineering scaffolds by the method of extrusion freeforming. To achieve this goal, BHA were added to sodium alginate(SA) solution to form a slurry system in appropriate proportion. The resulting mixtures were fabricated to be a kind of controllable and porous scaffolds followed with cross-linking in 5% calcium chloride(CaCl_2) solution for 24 h. After that, the scaffolds were sintered in air at 1 000, 1 100, 1 200 and 1 300 ℃ for 5 h. Scanning electron microscopy(SEM) and X-ray diffraction(XRD) studies were performed on the scaffolds to analyze its microstructure and constituent. To explore the effect of sintering temperature on scaffolds, the compressive strength, volume shrinkage and water absorptivity of BHA-SA composite scaffolds after sintering were investigated. The research tests indicated the feasibility of applying BHA powder to 3D printing. Besides, the scaffolds sintered in a respectively lower temperature possess much more pores and performed higher water absorptivity, which means better cellular affinity. And scaffolds sintered between 1 100 and 1 200℃ presents higher compressive strength.
基金Supported by Key Project of National Water Pollution Control and Treatment Science and Technology(2014ZX07211-001)Demonstration Study on Integration Model of Environmental Public Utilities in Industrial Parks of Key Watershed(2014ZX07211-001-04)
文摘In order to protect quality of Baiyangdian surface water and Gaoyang groundwater,the project is applied to process printing and dyeing wastewater that contains complicated compositions,high concentrations of organics and SS,and lots of pollutants difficult to degrade by microorganism. The process and operating parameters of project are optimized and debugged,and its economic and environmental benefits are analyzed.The results show that the process of coagulation sedimentation-hydrolytic acidification with aeration tank-biological aerated filter-active sand filter is applied in Gaoyang Sewage Treatment Plant. The design scale of sewage treatment plant is 120000 m^3/d. The influent is as following: COD is 669mg/L; SS is 424mg/L; NH_3-N is 8.83mg/L; TP is 6.03mg/L. After the process,the best removal rates of COD,SS,NH_3-N and TP are 93. 5%,98. 8%,97. 1% and 96. 2%,respectively. The various indexes of effluent water complied with standard A of the first order in Pollutants Emission Standard of Urban Wastewater Treatment Plant( GB 18918-2002). The processing cost is only 0. 807 yuan/m^3. As a result,the project construction and operation not only improve the environment,but also promote regional economic development. Process design and operating parameters provide an important reference value for the printing and dyeing wastewater treatment industry.
