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利用新兴的嵌入式Intetnet技术,吸取国内外数控系统的优点,研制了一种基于嵌入式网络互连的新一代数控测井地面系统。该系统软件上采用客户/服务器模式,利用装载在PC104上的客户机进行实时数据采集,安装在普通PC机上的服务器进行复杂的后期数据处理操作;硬件结构紧凑,外部连线少且操作简单,主要以挂接普通的生产测井仪器为主。并且很容易扩展和挂接新的测井仪。这种设计思路利用了嵌入式设备的实时性、低功耗等特点,还充分利用了现代PC的多媒体性能和高速的处理能力,以网络为中介,突破了空间限制,是对嵌入式Internet技术和现代数控测井技术的有效结合的成功尝试。 相似文献
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Various lead-free ceramics have been investigated in search for new high-temperature dielectrics. In particular, Bi4Ti3O12 is a type of ferroelectric ceramics, which is supposed to replace leadcontaining ceramics for its outstanding dielectric properties in the near future. Ferroelectric ceramics of Bi4Ti3O12 made by conventional mixed oxide route have been studied by impedance spectroscopy in a wide range of temperature. X-ray diffraction patterns show that Bi4Ti3O12 ceramics are a single-phase of ferroelectric Bi-layered perovskite structure whether it is calcined at 800 °C or after sintering production. This study focused on the effect of the grain size on the electric properties of BIT ceramics. The BIT ceramics with different grain sizes were prepared at different sintering temperatures. Grain becomes coarser with the sintering temperature increasing by 50 °C, relative permittivity and dielectric loss also change a lot. When sintered at 1 100 °C, r values peak can reach 205.40 at a frequency of 100 kHz, the minimum dielectric losses of four different frequencies make no difference, all close to 0.027. The values of E a range from 0.52 to 0.68 eV. The dielectric properties of the sample sintered at 1 100 °C are relatively better than those of the other samples by analyzing the relationship of the grain, the internal stresses, the homogeneity and the dielectric properties. SEM can better explain the results of the dielectric spectrum at different sintering temperatures. The results show that Bi4Ti3O12 ceramics are a kind of dielectrics. Thus, Bi4Ti3O12 can be used in high-temperature capacitors and microwave ceramics. 相似文献
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一、工艺简介及要求硝酸铵生产的主要工序是用氨和稀硝酸在中和器内进行中和反应,得到稀硝酸铵溶液,经再中和器进一步与氨中和及二段蒸发浓缩处理后,送至结晶器进行真空结晶,得到硝酸铵成品。生产过程中要求对中和器、再中和器的pH值以及二段蒸发器硝酸铵溶液的出口温度进行严格地控制。 相似文献
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