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71.
The cable-stayed suspension bridge is one type of bridge that has been increasingly applied to bridge engineering, especially in cross-sea projects. However, the complex combined system of this type of bridge makes it quite difficult for researchers to make a quick decision of the parameter values during the design stage. The Hellinger–Reissner method is applied here to analyze the deformation and force of the structural members in the bridge. The advantage of this method is that the solving of deformation and force is independent of each other, which would enhance the accuracy of the final results. Different load conditions are also considered in the analysis. The results from the present method are compared with test results and finite element analysis, and show good agreements. It implies that the Hellinger–Reissner is a comparatively more efficient method to help designers choose the key parameters for cable-stayed suspension bridges. 相似文献
72.
浅谈血液制品生产厂房工艺设计 总被引:1,自引:0,他引:1
结合具体项目,介绍了按照国家2010版GMP规范及参照欧盟GMP规范设计的某血液制品生产车间的工艺布局特点和设计创新点,该设计突破了以往设计思路,引入了国外先进的设计理念,最大限度的减少了交叉污染。 相似文献
73.
采用正交设计,以苦杏仁中指标成分苦杏仁甙的含量为指标,对必止咳胶囊的制剂工艺条件进行试验考察,优选出最佳生产工艺路线及提取工艺条件. 相似文献
74.
目的 研究辣椒碱表面活性剂泡囊的处方设计.方法 采用注入法制备辣椒碱表面活性剂泡囊,以包封率为评价指标,评价不同组成材料制备的辣椒碱表面活性剂泡囊.结果 得到9种辣椒碱表面活性剂泡囊处方,其平均包封率均≥75%,粒径分布为5~30 μm,平均粒径均≤10 μm.结论 本文筛选得到9种包封率较高、粒径大小理想的辣椒碱表面活性剂泡囊处方,为进一步的研究奠定了基础. 相似文献
75.
Hu Xu Dan Liu Wei-Qiang Sun Rong-Jun Wu Wu Liao Xiao-Ling Li Guang Hu Hua-Si Hu 《Materials》2022,15(9)
Polymers have an excellent effect in terms of moderating fast neutrons with rich hydrogen and carbon, which plays an indispensable role in shielding devices. As the shielding of neutrons is typically accompanied by the generation of γ-rays, shielding materials are developed from monomers to multi-component composites, multi-layer structures, and even complex structures. In this paper, based on the typical multilayer structure, the integrated design of the shield component structure and the preparation and performance evaluation of the materials is carried out based on the design sample of the heat-resistant lightweight polymer-based interlayer. Through calculation, the component structure of the polymer-based materials and the three-layer thickness of the shield are obtained. The mass fraction of boron carbide accounts for 11% of the polymer-based material. Since the polymer-based material is the weak link of heat resistance of the multilayer shield, in terms of material selection and modification, the B4C/TiO2/polyimide molded plate was prepared by the hot-pressing method, and characterization analysis was conducted for its structure and properties. The results show that the ball milling method can mix the materials well and realize the uniform dispersion of B4C and TiO2 in the polyimide matrices. Boron carbide particles are evenly distributed in the material. Except for Ti, the other elemental content of the selected areas for mapping is in good agreement with the theoretical values of the elemental content of the system. The prepared B4C/TiO2/polyimide molded plate presents excellent thermal properties, and its glass transition temperature and initial thermal decomposition temperature are as high as 363.6 °C and 572.8 °C, respectively. In addition, the molded plate has good toughness performs well in compression resistance, shock resistance, and thermal aging resistance, which allows it to be used for a long time under 300 °C. Finally, the prepared materials are tested experimentally on an americium beryllium neutron source. The experimental results match the simulation results well. 相似文献
76.
Rizwan Azam Muhammad Rizwan Riaz Muhammad Umer Farooq Faraz Ali Muhammad Mohsan Ahmed Farouk Deifalla Abdeliazim Mustafa Mohamed 《Materials》2022,15(9)
In the past, many studies have been conducted on the optimization of reinforced concrete (RC) structures. These studies have demonstrated the effectiveness of different optimization techniques to obtain an economical design. However, the use of optimization techniques to an obtain economical design is not so practical due to the difficulty in applying most of the optimization techniques to achieve an optimal solution. The RC beam is one of the most common structural elements encountered by a practising design engineer. The current study is designed to highlight the potential of the Solver tool in MS Excel as an easy-to-use option for optimizing the design of simply supported RC beams. A user-friendly interface was developed in a spreadsheet in which beam design parameters from a typical design can be entered and an economical design can be obtained using the Evolutionary Algorithm available in the MS Excel Solver tool. To demonstrate the effectiveness of the developed optimization tool, three examples obtained from the literature have been optimized. The results showed that up to 24% economical solution can be obtained by keeping the same material strengths that were assumed in the original design. However, if material strength is also considered as a variable, up to 44% of the economical solution can be obtained. A parametric study was also conducted to investigate the effect of different design variables on the economical design of simply supported RC beams and to derive useful rules of thumb for their design and proportioning, with the objective of cost minimization. The results of the parametric study suggest that the grade of the reinforcing steel is one of the most influential factors that affect the cost of simply supported RC beams. Practicing engineers can use the trends derived from this research to further refine their optimal designs. 相似文献
77.
维生素D3—β—环糊精包合物的制备及鉴定 总被引:7,自引:2,他引:7
探讨优化维生素D3-β-环糊精包合物的制备方法并鉴定其形成。方法:以维生素D3利用率和收率为综合指标研究了溶液法、胶体磨法、超声波法和研磨法等制备维生素D3-β-环糊精包合物的方法。结果:当β-环糊精和维生素D3以3:1摩尔量投料时维生素D3利用率和收率最高。 相似文献
78.
79.
网络环境下教师指导性活动的设计 总被引:5,自引:1,他引:5
网络教学为学生的学习提供了丰富的资源,拓延了教学时空的维度,对现有的教学内容、教学手段和教学方法提出了挑战。本文探讨了在此环境下教师指导活动的内容,设计原则及其设计方法等问题。 相似文献
80.
目的 本研究通过分析种植体术前设计和术后的三维位置,来评估数字化口腔种植导板的精确度.方法 根据修复体的生物学功能和美学要求,使用3D种植软件对种植体位置进行设计.将设计的种植导板转化为手术用种植导板,指导47颗种植体植入合适位置.通过重叠术前和术后的CT扫描图像,分析植体肩部和根部的线性误差以及植体长轴的角度误差,比... 相似文献