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51.
新桥硫矿首次在国内推行露天开采下盘无台阶采矿新工艺,该工艺具有剥岩少、基建快、出矿早、采矿工程延深快等特点。由于该工艺具有独特的靠帮方式和端部过渡方式,需严格控制底盘因爆破而导致的岩体滑动。该工艺的实施已取得了显著的经济效益。 相似文献
52.
53.
Heat‐curable silicone rubber (HCSR) was prepared by using vinyl‐containing silicone resin (VSR) as the crosslinking agent instead of polyvinylsilicone oil (C gum). Mechanical properties and crosslink density of the vulcanizates were measured. The results indicate that VSR is a good crosslinking agent for HCSR. The tensile strength, tearing strength, elongation at break, and hardness of the vulcanizate can reach 10.2 MPa, 29.1 kN/m, 720%, and 58 SHA, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3123–3127, 2002; DOI 10.1002/app.10054 相似文献
54.
曹阳 《电脑编程技巧与维护》2014,(4):11-12
随着我国集装箱吞吐量的快速增长,集装箱港口对作业效率的要求也越来越高。在现有作业技术水平和硬件设备、设施的基础上实现作业效率的提高,已经成为集装箱港口发展所面临的重要问题。从集装箱港口作业的一个环节——集卡作业入手,分析提高集卡利用率,进而带动整个港口作业效率的提高。 相似文献
55.
搅拌设备设计的几点体会 总被引:1,自引:0,他引:1
从搅拌轴的支承条件、轴承间最佳距离的确定以及搅拌轴的稳定器等几个方面讨论 ,分析了其对搅拌设备设计的影响 ,并提出了相应的措施和方法。 相似文献
56.
Yuxin Yin Zhengguo Jin Feng Hou Xu Wang 《Journal of the American Ceramic Society》2007,90(8):2384-2389
Titanium dioxide (TiO2 ) nanotube arrays were prepared by electrochemical anodization of titanium sheets in the glycerol 176 mL/H2 O 44 mL/NH4 F 0.5 wt% electrolytes modified with H2 SO4 and NaAc addition. The surface morphologies, average inner diameter, and the length of the nanotube arrays changed with the solution pH in the range from 5.6 to 4.0 by adding H2 SO4 . A uniform surface morphology of the nanotubes with average inner diameter of ∼80 nm and a length of ∼1000 nm was obtained when the solution pH was 5.0. The growth rates of the nanotubes were remarkably enhanced by NaAc addition in the range of 0.04–0.14 M . With NaAc addition of 0.10 M , the length of the nanotube arrays reached 4.16 μm after an 8-h anodization, increasing 3.23 μm compared with no NaAc addition. The relationship between solution pH and growth of TiO2 nanotubes was analyzed by current–time curves, solution electrical conductivities, and scanning electron microscopy (SEM), and the role of NaAc was also discussed based on SEM and solution electrical conductivities. 相似文献
57.
A novel and simple growth mark method was developed to make marks during the growth process of carbon nanotube arrays. These marks can be read out under scanning electron microscope or optical microscope. Based on this method, the growth rates at different temperatures and under different acetylene partial pressures were measured, from which the activation energy and the order of reaction were determined. Based on our experimental results, the growth of carbon nanotube arrays in our experimental condition could not be diffusion-limited. The measured activation energy could possibly be attributed to the heterogeneous decomposition of acetylene over the catalyst particle. Furthermore the marked array with special segmental structure may be found some applications in the future. 相似文献
58.
The structure of benzoxazines is similar to that of phenolic resin through thermal self‐curing of the heterocyclic ring opening reaction that neither requires catalyst nor releases any condensation byproduct. These polybenzoxazine resins have several outstanding properties such as high thermal stability and high glass transition temperature. To better understand the curing kinetics of this copolybenzoxazine thermosetting resin, dynamic and isothermal differential scanning calorimetry measurements were performed. Three models, the Kissinger method, the Flynn–Wall–Osawa method, and the Kamal method, were used to describe the curing process. Dynamic kinetic activation energies based on Kissinger and Flynn–Wall–Osawa methods are 72.11 and 84.06 KJ/mol, respectively. The Kamal method based on an autocatalytic model results in a total order of reaction between 2.66 and 3.03, depending on curing temperature. Its activation energy and Arrhenius preexponential are 50.3 KJ/mol and 7959, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 730–737, 2005 相似文献
59.
Dissolved oxygen in the steel at the terminal of the converter smelting process is the main cause for the formation of oxide inclusions, and the high terminal oxygen content worsens the steel cleanness. However, post stirring in a combined blowing converter can promote the carbon-oxygen reaction in the liquid steel and reduce the dissolved oxygen content at the terminal of the converter smelting process. Thus, the mathematical model of deoxidization in the post stirring process was obtained, and the rationa... 相似文献
60.
建设工程涉外设计合同风险防范 总被引:2,自引:0,他引:2
中国参加WTO后,在扩大对外开放、拉动内需保增长政策指导下,一大批重点建设工程陆续上马,有许多外国设计企业及其在华机构加入中国建设工程的设计,其中,国有独资项目占据很大的比重。笔者结合参与全国十运会场馆一南京奥体中心以及江苏省人民医院扩建、南京图书管等多个大型项目工程全程法律保障实践,就工程设计合同风险防范,一舒管见。 相似文献