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转炉钢渣的风化膨胀随着时间的增长而增加,并且将延续相当一段时间,为测定渣的风化程度需采用95℃至100℃的饱和蒸汽处理的快速试验方法。渣块经蒸汽处理后,粉化碎裂程度可反应渣的长期风化程度。一般经4小时左右的处理时间即可。 相似文献
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This paper describes the analysis and design of a 0.13μm CMOS tunable receiver front-end that supports 8 TDD LTE bands,covering the 1.8-2.7 GHz frequency band and supporting the 5/10/15/20 MHz bandwidth and QPSK/16QAM/64QAM modulation schemes.The novel zero-IF receiver core consists of a tunable narrowband variable gain low-noise amplifier(LNA),a current commutating passive down-conversion mixer with a 2nd order low pass trans-impedance amplifier,an LO divider,a rough gain step variable gain pre-amplifier,a tunable 4th order Chebyshev channel select active-RC low pass filter with cutoff frequency calibration circuit and a fine gain step variable gain amplifier.The LNA can be tuned by reconfiguring the output parallel LC tank to the responding frequency band,eliminating the fixed center frequency multiple LNA array for a multi-mode receiver. The large various gain range and bandwidth of the analog baseband can also be tuned by digital configuration to satisfy the specification requirement of various bandwidth and modulation schemes.The test chip is implemented in an SMIC 0.13μm 1P8M CMOS process.The full receiver achieves 4.6 dB NF,-14.5 dBm out of band IIP3, 30-94 dB gain range and consumes 54 mA with a 1.2 V power supply. 相似文献
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DZ-200型多功能钻机研制及其在浅层地埋管孔施工中的应用 总被引:1,自引:0,他引:1
针对地埋管孔工程的施工需求,并兼顾工程勘查、锚固施工等施工工艺要求,研发了一种轻型、高效、适用于回转、冲击回转等多种钻进工艺的DZ-200型多功能钻机。主要介绍了该钻机的结构特点、技术参数以其在地源热泵浅层地埋管孔施工中的应用效果。 相似文献
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