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矸石山自燃爆炸的成因及其对策 总被引:2,自引:0,他引:2
文章介绍了全国几起历石山自然爆炸的典型事例,论述了发生瀑作具备的三个条件.提出了防治砰石山自燃煤作的对策。 相似文献
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以OP-10-SDS/正丁醇/环己烷/水四元复配微乳液体系为反应介质、以KBH4为还原剂,在50℃还原氯化镍和硝酸铈制备了超细Ni-Ce-B非晶态合金,利用TEM、SEM、TG-DSC、XRD等手段对产物的形貌、结构、热稳定性和晶化性质进行了研究,并通过改变水相的组成来考察水核大小对合成产物平均粒径的影响.结果表明:在微乳液中可得到平均粒径30 nm左右的超细Ni-Ce-B非晶态合金,其颗粒大小均匀,分散性良好;超细Ni-Ce-B非晶态合金的平均粒径随着ψ值(水和复配表面活性剂的摩尔比)及水核半径的增大而增大;超细Ni-Ce-B非晶态合金的晶化温度较Ni-B非晶态合金的晶化温度升高了近360℃. 相似文献
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By using enhanced reduced instruction set computing(RISC) architecture and carrying out powerful instructions in a single clock cycle,the ATmega128 achieves the data transmission speed of about one MIPS per MHz.With this advantage,the designer can eliminate the contradiction between power consumption and processing speed in data acquisition system based on U disk.In this paper,a U disk recorder for mass data storage is designed.It consists of a microcontroller ATmega128 and a U disk management chip CH376.ATmega128 with 4 KB SRAM provides enough buffer memory and CH376 enables U disk files to be written or read in sector size.Based on analysis of the system,the hardware and software designs are given.With the designed data acquisition system,data transmission speed can reach 460 KB per second.The experimental results show that the designed system has higher efficiency and reliability than the traditional ones when writing or reading U disk files. 相似文献
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介绍用差示扫描量热法(DSC)测定结晶物质纯度的原理和实验过程,讨论了Van'tHoff方程和DSC法对间苯二酚二羟乙基醚(HER)样品的适用性,用DSC法测定了不同厂家、不同批次的几种HER产品的纯度。当样品纯度(摩尔分数)高于98.0%时,平行测定结果之差≤0.1%(绝对差),测定结果与高效液相色谱法(HPLC)一致。在测定纯度的同时,测得HER的理论熔点(无限纯样品的熔点)为89.48±0.05℃,熔融热为39.4±0.7J/mol。 相似文献
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将溶胶-凝胶法与微乳液化学剪裁法相结合,以钛酸丁酯和氯化锌制备凝胶,在OP-10-SDS/正丁醇/环己烷/水复配微乳体系中进行化学剪裁制备前驱物,再经煅烧制备了组成单一的球状纳米ZnTiO3粉体,通过XRD、TEM、SEM、TG-DSC等方法对产物进行了表征,并讨论了凝胶的陈化时间、煅烧温度和煅烧时间对纳米ZnTiO3的组成、粒径和形貌的影响,提出了纳米ZnTiO3可能的形成机理。结果表明,在700℃煅烧2h制备的纳米ZnTiO3平均粒径为35nm,粒径分布比较均匀,基本呈单分散;适当延长陈化时间会减少ZnO及TiO2杂质;随着煅烧时间的延长,ZnTiO3晶体粒径开始增大;煅烧温度过高会使六方相ZnTiO3分解为立方相的Zn2TiO4和金红石型TiO2。 相似文献