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1.
Xueru Chen Yin Zhang Dashui Yuan Wu Huang Jing Ding Hui Wan Wei-Lin Dai Guofeng Guan 《材料科学技术学报》2021,71(12):211-220
Porous g-C3N4 nanosheets (PCN) were prepared by the nickel-assisted one-step thermal polymerization method.Hydrogen (H2) which was produced by the reaction between nickel (Ni) foam and ammonia (NH3) defined the structure and properties of PCN.During the formation of PCN,the participation of H2 not only enhanced the spacing between layers but also boosted the specific surface area that more active sites were exposed.Additionally,H2 promoted pores formation in the nanosheets,which was beneficial to the transfer of photons through lamellar structure and improved the absorption efficiency of visible light.Remarkably,the obtained PCN possessed better Cr(Ⅵ) photocatalytic reduction efficiency than pure g-C3N4.The reaction rate constant (k) of PCN (0.013 min-1) was approximately twice that of bare g-C3N4 (0.007 min-1).Furthermore,the effects of original pH and concentration of Cr(Ⅵ)-containing solution on removal efficiency of Cr(Ⅵ) were explored.A possible photocatalytic mechanism was proposed based on the experiments of radical scavengers and photoelectrochemical characterizations. 相似文献
2.
As one of the vital steps in the 3rd phase of China’s lunar exploration program(CLEP),the circumlunar return and reentry spacecraft,developed by China Academy of Space Technology(CAST),is used to demonstrate the key technologies of hyper-speed return and reentry spacecraft.The system configuration and flight process are presented in this paper,as well as the analysis of mission characteristics,the key technologies and the technical advancement during the RD progress.The significance of circumlunar return and reentry spacecraft is given at the end. 相似文献
3.
目前为了适应我国现代社会经济的发展要求,水利工程的数量也在不断增多,由于水利工程其建设规模的扩大使水土流失问题逐渐显露出来。针对此种情况则需要在水利工程中通过水土保持工作的开展来降低水土流失问题的发生几率,通过提高水土保持率来预防自然灾害的形成,以此来提升水利工程水土保持工作开展的社会效益、生态效益。 相似文献
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In the early design stage, automotive modeling should both meet the requirements of aesthetics and engineering. Therefore, a vehicle CAD (computer aided design) model that can be easily adjusted by feedbacks is necessary. Based on CE-Bézier surface, this paper presents a set of algorithms for parametric segmentation and fairing surface generation in a car model. This model is defined by a simplified automotive template and relevant control points, shape parameters and segmentation parameters, which can be modified to alter the car form efficiently. With this model and the corresponding adjustment method, more than fifty various vehicle models are established in this research according to different parameters. And two methods for calculating similarity index between car models are constructed, which are suitable for brand design trend analysis and modelling design decisionmaking. 相似文献
6.
Silks have various advantages compared with synthetic polymer fibers,such as sustainability,mechanical properties,luster,as well as air and humidity permeability.However,the functionalization of silks has not yet been fully developed.Functionalization techniques that retain or even improve the sustainability of silk production are required.To this end,a low-cost,effective,and scalable strategy to produce TCSs by integrating yarn-spinning and continuous dip coating technique is developed herein.TCSs with extremely long length(>10 km),high mechanical performance(strength of 443.1 MPa,toughness of 56.0 MJ m?3,comparable with natural cocoon silk),and good interfacial bonding were developed.TCSs can be automatically woven into arbitrary fabrics,which feature super-hydrophobicity as well as rapid and programmable thermochromic responses with good cyclic performance:the response speed reached to one second and remained stable after hundreds of tests.Finally,applications of TCS fabrics in temperature management and dynamic textile displays are demonstrated,confirming their application potential in smart textiles,wearable devices,flexible displays,and human–machine interfaces.Moreover,combination of the fabrication and the demonstrated applications is expected to bridge the gap between lab research and industry and accelerate the commercialization of TCSs. 相似文献
7.
博斯腾湖泵站分东、西泵站二期建设,本文介绍了博斯腾湖东泵站工程电气一次设计中的接入系统设计、电气主接线、设备选择。 相似文献
8.
近年来,随着我国石油化工行业的迅速发展,液化石油气作为一种污染小、价格低、资源丰富的能源越来越受到重视,其应用日益广泛。液化石油气储罐是具有较大危险性的储存容器,一旦出现问题,将给人民的生命、财产带来极大的损失。吉林、西安等地的液化气储罐事故给人们以深刻的教训。为了保证液化石油气储罐的安全运行,避免事故发生,必须从各个方面严格把关。而设计是首要的环节。 相似文献
9.
我国高层建筑日益增多,在建或拟建的第二长途通信枢纽楼,其高度也已达200m左右。结合高层通信枢纽楼的特点,对高层建筑结构设计中的主要技术问题进行介绍。 相似文献
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