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81.
影响中厚板成材率因素的量化分析及对策   总被引:1,自引:0,他引:1  
刘朋  刘纯 《宽厚板》2005,11(5):32-34
本文量化分析了影响中厚板成材率的因素,并介绍了通过措施降低加热炉氧化烧损、提高负偏差控制水平、优化坯料结构实现倍尺轧制、扩大倍尺板生产比例和加强50mm晋级管理等措施,明显提高了中厚板成材率.  相似文献   
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83.
Field investigations of target air pollutants at two of the most famous temples in Hong Kong were conducted. The air pollution problems in these two temples during peak and non-peak periods were characterized. The target air pollutants included particulate matters (PM(10), PM(2.5)), volatile organic compounds (VOCs), carbonyl compounds, carbon monoxide (CO), nitrogen oxides (NO(x)), methane (CH(4)), non-methane hydrocarbons (NMHC), organic carbon (OC), elemental carbon (EC), and inorganic ions (Cl(-), NO(3)(-), SO(4)(2-), Na(+), NH(4)(+), and K(+)). The pollutant levels of the two temples during peak period were shown to be significantly higher than those during non-peak period. The highest average CO level was obtained at Temple 1 during peak period, which exceeded IAQO 8-h Good Class criteria. In general, the average PM(2.5)/PM(10) ratios were approximately 82%. The results revealed that the fine particulates (PM(2.5)) constituted the majority of suspended particulates at both temples. It was noted that formaldehyde was the most abundant carbonyl compounds, followed by acetaldehyde. At Temple 1 during peak period, the average benzene concentration exceeded almost 8 times more than Indoor Air Quality Objectives for Office Buildings and Public Places (IAQO) [HKEPD, 2003. Guidance notes for the management of indoor air quality in offices and public places. Indoor air quality management group, The Government of the Hong Kong Special Administrative Region.] Good Class criteria. The average OC/EC ratios ranged from 2.6 to 17 in PM(10) and from 4.2 to 18 in PM(2.5) at two temples, which suggested that OC measured in these two temple areas may be due to both direct emission from incense burning and secondary formation by chemical reactions. The total mass of inorganic ions, organic carbon, and elemental carbon accounted for about 71% in PM(2.5) and 72% in PM(10).  相似文献   
84.
吐哈盆地火焰山断裂带夹持于西部弧形带和生烃凹陷胜北次凹之间,油气怎样由胜北次凹向西运移值得研究。对火焰山断裂带演化历史和西部弧形带成藏期进行了分析,认为火焰山断裂带在早、中侏罗世表现为沿煤层滑脱的正断层,在侏罗纪末期发生轻微反转,强烈逆冲并定型于第四纪,油气藏形成主要有两期:白垩纪末期一早第三纪和早第三纪末一第四纪早期,油气的充注发生在火焰山断裂带形成之前。火焰山断裂对第四纪以前的油气运移并没有影响,但终止了第四纪以来油气向西运移,决定了油气藏以煤系油为主、规模小的特征。  相似文献   
85.
���������ڿ�ȼ��ȼ��й��ʵ���о�   总被引:3,自引:0,他引:3  
在直径为1 m的球形容器中,采用中心点火方式,对液化石油气进行了大量密闭燃爆和燃爆泄放的实验,得出了液化石油气最大破坏力的浓度范围5%~6%、密闭下燃爆最大压力与初始压力呈线性关系,并基于不同条件下燃爆泄放实验,通过量纲分析将泄放面积、容器内表面积、容器体积、泄放压力及初始压力等关联成燃爆泄放状态准数,建立了燃爆泄放最大超压与泄放准数之间关系式,关系式覆盖的体积范围(0.029~213 m3),内部初始压力范围(0.1~0.4 MPa),泄放压力与初始压力比(1~2.5)、容器长径比(1~2),在该范围内关系式与实验结果吻合较好。  相似文献   
86.
Dynamic stabilization of D—T burn in Tokamak reactors   总被引:1,自引:0,他引:1  
A simple,engineeringly feasible dynamic method is supposed to control the deuterium-tritium burn process in Tokamak reactors operated in an advanced scenario.The thermal transport of the D-T plasma is described by an anomalous thermal conduction which is a radially increasing function and the central conduction value is proportional to the central temperature of the plasma.The dynamic external heating power is selected to be inversely proportional to certain power function of this temperature,As a result,the D-T burn can undergo in controllable way in different temperature regimes with different power output.Anomalous alpha particle transport effect is taken into account.It can affect the resultant plasma equilibrium ,the reactor efficency,the operation mode and so on.  相似文献   
87.
无烟煤作水泥生产用燃料是一个牵涉烧成系统乃至煤粉制备系统的新技术。不同类型的回转窑在用无烟煤作燃料时的技术有所区别。对预分解窑来讲,必须提高无烟煤在分解炉中的燃烧温度、时间和空间,减少CaCO3分解过程同一时间的吸热量,改善无烟煤着火和燃烧的环境。  相似文献   
88.
In a systematic study to compare the effects of the values of burning rate and pressure exponent in RDX‐AP based composite propellant, various compositions with varying percentages of zirconium carbide (ZrC) and zirconium silicate (ZrSiO4) were formulated to select a suitable candidate. Various rocket parameters of each formulation were theoretically predicted by the NASA CEC‐71 program and the burning rate was evaluated in pressure range of 3–11 MPa. In addition, density, sensitivity, and thermal properties of compositions having maximum effects on pressure exponent’s values were also evaluated. It was concluded that ZrSiO4 enhances the pressure exponent “n” value substantially, whereas ZrC doesn’t have significant effects on it as compared to base composition and also provides higher density values of composite propellant formulated.  相似文献   
89.
本文用异丙醇钛经溶胶-凝胶过程制得了二氧化钛粒子溶胶,确定成膜时的烧结温度,制得的膜经SEM测试具有典型的不对称结构,用压汞法测量孔径分布在2.7-11nm范围内。  相似文献   
90.
诸爱珍 《山东陶瓷》2003,26(6):28-31
本文探讨了滑石瓷烧结范围窄的原因,提出了解决该问题的办法,即加入适量的添加剂拓宽烧结范围;选用温度均匀的窑炉烧成;制定合理的烧成制度。  相似文献   
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