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1.
针对目前工业CT图像转换为3D打印G代码方法效率低的问题,提出一种基于邻层数据匹配的工业CT图像直接转换成G代码的方法。首先采用Canny算子提取工业CT图像的轮廓,然后处理轮廓分叉问题,实现邻层间几何信息数据匹配,其次进行邻层间轮廓插值以满足3D打印层间厚度要求,从而避免"阶梯效应",最后通过填充编码得到用于3D打印的G代码。使用本文提出的方法,轮毂CT图像转换为G代码的时间为10.5 s,耗时远小于其他间接转换方法;3D打印出的轮毂无"阶梯效应",平均尺寸误差率为0.25%。实验结果表明,该方法不涉及中间格式,转换效率高,转换误差与传统方法相当,适用于具有复杂内腔结构的零件。 相似文献
2.
Kedong Xia Shuoshuo Yu Yunling Li Huijuan Han Lingyao Duan Zhenyu Hou Xiao Liu 《Journal of the European Ceramic Society》2021,41(4):2375-2385
In this study, C/SiOC and C/SiO2 composites were prepared by using carbonaceous microspheres with different surface functional groups. Carbonaceous microspheres based on hydrothermal reaction of glucose contains hydroxyl group, while the surface carboxyl group increases after NaOH etching. The hydroxyl group increases the oxygen-enriched structural units of SiOC ceramics, and the C spheres are closely enwrapped in SiOC matrix after pyrolysis at 900 °C. However, the interfacial reaction of surface carboxyl with Si–OH results in the formation of cristobalite SiO2, and C spheres are not only encased inside the SiOC matrix, but also dispersed outside of SiOC ceramics. After removal of C via calcination at 500 °C for 5 h, C/SiOC and C/SiO2 composites are transformed into amorphous SiO2 and cristobalite SiO2, respectively. The thermogravimetric analysis indicates the oxidation resistance of SiOC is superior to that of C and SiO2. 相似文献
3.
4.
Weiwen Wang Hui Zhao Peng Pan Kang Xue Zisheng Zhang Jihai Duan 《Ceramics International》2021,47(5):6094-6104
In order to enhance the photocatalytic activity of TiO2 under visible light, Ag nanoparticles were introduced into tridoped B–C–N–TiO2 (TT) catalyst by photoreduction deposition. Ag/B–C–N–TiO2 (ATT) catalysts with the functions of reducing band gap and carrier recombination were prepared. At the same time, the effect of the amount of Ag on the photocatalytic performance of ATT catalyst was investigated. Through XRD, XPS, PL and other characterization methods, the (211)/(101)/Ag interface heterojunction mechanism similar to the traditional Z-scheme heterojunction was proposed. The intervention of Ag nanoparticles changed the P–N interface heterojunction between (211)/(101) to the (211)/(101)/Ag Z-scheme interface heterojunction. The results show that ATT catalyst exhibits the highest photocatalytic activity when the molar amount of Ag is 0.005% with the MB degradation rate of the ATT catalyst (0.01707 min?1), which is 14.59 times of TiO2 (0.00117 min?1) and 2.02 times of TT (0.00847 min?1). In addition, the four cycles efficiencies of ATT for MB degradation were all above 94.00%.This study reveals the possibility of construction of Z-scheme heterojunctions between precious metal nanoparticles and different interfaces of TiO2, and provides a reference for the construction of Z-scheme interface heterojunctions. 相似文献
5.
Nianxiu Duan Junjun Li Sha Song Feng Wang Yiwei Yang Di Nie Caifen Wang Yingjie Sheng Yali Tao Jie Gao Can Xu Yan Wei Yong Gan 《Advanced functional materials》2021,31(46):2100605
Tumor-specific enhanced delivery of chemotherapeutics and modulators to tumor cells and activated pancreatic stellate cells (aPSCs), respectively, represents safer and more effective therapy for pancreatic cancer. Herein, a membrane type 1-matrix metalloproteinase (MT1-MMP)-cleavable spacer is used to assemble low-density cRGDfK onto thermosensitive liposomes loaded with phosphorylated calcipotriol (PCAL) and doxorubicin (DOX), yielding MR-T-PD. The liposome-linked cRGDfK prodrug on MR-T-PD surface is first activated by MT1-MMP, which is selectively expressed on tumor endothelial cells, to release cRGDfK. The free cRGDfK specifically promotes tumor angiogenesis, leading to 3.4-fold higher accumulation and a wider distribution of MR-T-PD in tumors. Furthermore, MR-T-PD rapidly releases PCAL and DOX into the interstitium under heat treatment. The released DOX enters tumor cells to induce apoptosis, whereas the PCAL prodrug is converted to CAL by alkaline phosphatase on the surface of aPSCs; CAL can then enter aPSCs to induce quiescence and promote the antitumor effect of DOX. Finally, by enhancing the exposure of DOX and CAL to tumor cells and aPSCs, respectively, in a tumor-specific manner, MR-T-PD exerts superior efficacy (a 5.9-fold decrease in tumor weight) without causing additional side effects. Overall, this prodrug-based smart liposome system represents a promising paradigm for pancreatic cancer therapy. 相似文献
6.
针对燃煤工业锅炉尾气处理装置存在的不足,分析一种节能型燃煤工业锅炉尾气处理装置.对该装置的结构、工作原理、特点进行了分析.将该装置安装应用在云岗矿燃煤工业锅炉上,污染物减排效果明显,为企业创造了较好的社会经济效益. 相似文献
7.
采用不同淬回火工艺系统地研究了一种高碳高铬马氏体刀具用钢—SIMR的热处理工艺和微观组织,通过XRD、SEM和TEM等表征方法,分析测试了不同淬火温度和回火温度下SIMR刀具用钢的微观组织、碳化物形貌与分布和显微硬度等,获得了SIMR的最佳热处理工艺。结果表明,SIMR刀具用钢的晶粒尺寸随着淬火温度的升高而逐渐增大,冶炼凝固过程中析出的富铬M7C3型一次碳化物随着淬火温度的提高而逐渐回溶,显微硬度总体上呈现先升高后降低的趋势,回火温度在150~300 ℃间,SIMR刀具用钢的最佳热处理工艺为在1050 ℃淬火处理20 min,油冷,然后在150 ℃回火处理90 min,空冷。 相似文献
8.
Wenxuan Pan Weidong Xuan Fangmiao Duan Xiaolong Bai Baojun Wang Zhongming Ren 《International Journal of Applied Ceramic Technology》2021,18(6):2284-2292
Mullite fibers composite silica-based ceramic cores were successfully prepared by injection molding. The effects of mullite fibers on the mechanical and thermal properties of ceramic cores were investigated. The results indicated that the linear shrinkage was significantly decreased and the porosity was gradually increased with the increase of mullite fibers. In addition, the flexural strength for the room temperature and the simulated casting temperature of 1500°C was increased to a maximum value when the content of mullite fibers was about 1 wt.%, and then decreased with the increase of mullite fibers. The mullite fibers of 1 wt.% presented excellent mechanical properties with a linear shrinkage of .65%, a porosity of 6.96%, and a flexural strength of 17 MPa at room temperature and 34.83 MPa at the simulated casting temperature of 1500°C. Besides, the change in microstructure and properties in various contents of mullite fibers were analyzed. 相似文献
9.
综合应用岩心、测井、地震等资料,对塔里木盆地塔河地区寒武系沉积体系的类型、内部结构以及沉积相分布开展了定性分析和地层沉积正演模拟研究,重现了寒武纪碳酸盐岩台地的演化过程,并依据定量表征的各时期沉积相展布规律,结合模拟参数分析,探讨了寒武纪碳酸盐台地的形成与演化机制。研究结果表明,塔河地区经历了发育早寒武世玉尔吐斯组沉积期陆棚、肖尔布拉克组沉积期碳酸盐岩缓坡(初期以发育中缓坡—外缓坡的低能沉积为主,晚期以发育中缓坡的高能丘滩为主)、吾松格尔组沉积期碳酸盐弱镶边台地(台缘发育1期加积-进积型微生物礁滩)、中—晚寒武世大型进积型碳酸盐岩强镶边台地(台缘分别发育3期进积型微生物礁滩)的演化过程。塔河地区沉积体系整体呈现出的多类型、多期次、多级层序结构特征,是全球海平面变化与差异沉降共同控制的物理可容空间,以及碳酸盐沉积物生产(类型、数量、聚集能力、发育位置)和水动力搬运作用耦合的结果。东西分异的沉降作用和初始地形影响着寒武纪碳酸盐岩台地迁移趋势;沉积物类型、水动力搬运作用以及海平面振荡的共同作用导致研究区在肖尔布拉克组沉积期形成碳酸盐岩缓坡并发生阶段分异;物理可容空间和生态可容空间的相互作用是研究区在早寒武世晚期由碳酸盐岩缓坡向弱镶边台地演化以及在中—晚寒武世形成大型进积镶边台地的关键控制因素。 相似文献
10.
Ai Li Wang Zhenyan Zhao Jianfu Zhu Pengfei Jiang Hechun Duan Xiulan 《Journal of Materials Science: Materials in Electronics》2022,33(13):10360-10367
Journal of Materials Science: Materials in Electronics - Co-doped LaMgAl11O19 microcrystals were synthesized by a facile sol–gel method. The as-synthesized microcrystals were near hexagonal... 相似文献