排序方式: 共有36条查询结果,搜索用时 23 毫秒
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低温灌注保存箱可保证移植肾在摘离人体后的质量,而目前存在的保存箱内温度不均、设备运行时间短等不足会影响移植肾的保存质量。针对这些不足,通过加装一套小型半导体制冷系统,该保存箱可在两小时内将箱内仿离体肾脏降至4℃,并稳定运行时长达35小时。实验结果表明,新型保存箱提升了使用性能,离体肾脏保存温度得到保障,病人术后生存质量和存活率也得以提高。 相似文献
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改革开放的大浪,激励着培养人才的高等教育领域研究如何凭借高校教育、科研的优势与扎实的理论基础、丰富的文献资料、熟练的实验技巧及先进的仪器设备等优越条件,为促进高、新、尖技术的飞速发展和把高科技成果转化为生产力作出贡献。同时培养各级各层次的建设人才,这个问题已现实地摆在我们的面前。按我们前几年厂、所、校联系办学的探索、实践,在下面 相似文献
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高速摄影技术在土业生产,科学技术领域,特别是在国防建设方面已经得到很广泛的应用,成为一种不可缺少的测试方法和研究手段。在农业以及与农业有关的各个领域中,高速摄影技术也得到了一些成功的应用。但它还不如在上述几个方面应用得广泛。 相似文献
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金属有机框架材料(MOFs)是一种制备过渡金属-氮-碳(M-N-C)氧还原电催化材料的有效前驱体,但在热解过程中结构坍塌等问题限制了其实际应用。本研究通过表面活性剂F-127包覆以及Zn掺杂对ZIF-67进行改性,并对改性后的Zn-ZIF-67@F-127在氩气气氛下进行热解,制得结构完整的Co-N-C载体。通过在Co-N-C载体表面进行Pt的负载,制备了Pt/Co-N-C复合氧还原反应(ORR)催化剂,并对其在碱性电解液中的ORR催化性能进行了探究。实验结果表明,F-127的加入提高了Zn-ZIF-67@F-127在热解过程中的形貌保持率,Pt/Co-N-C在O2饱和的0.1 mol·L-1 KOH中,催化剂的起始电位、半波电位、极限扩散电流密度分别为1.027 V、0.836 V和5.51 mA·cm-2,与商用20%Pt/C性能相近。Pt与Co-N-C的协同作用使得催化剂不仅对ORR的四电子路径显示出高选择性,更在计时电流测试中表现出接近于商用20%Pt/C的稳定性与较商用20%Pt/C更优的抗甲醇性能。 相似文献
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Excitation spectrum and structure factor of a two-component Bose-Einstein condensate in different hyperfine states 下载免费PDF全文
The elementary excitation spectrum of a two-component Bose-Einstein condensate in different hyperfine states is obtained by Green's function method. It is found to have two branches. In the long wave-length limit, the two branches of the excitation spectrum are reduced to one phonon excitation and one single-particle excitation. The single-particle one has an energy gap. When the energy gap exists, we study the Landau critical velocity and the depletion of the condensate. With the obtained Green's functions, we calculate the structure factor of a two-component condensate. It is found that the static structure factor comprises only the branch of the phonon excitation and the single-particle excitation makes no contribution to the structure factor. 相似文献
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Small-angle neutron scattering study on the stability of oxide nanoparticles in long-term thermally aged 9Cr-oxide dispersion strengthened steel 下载免费PDF全文
Peng-Lin Gao 《中国物理 B》2022,31(5):56102-056102
A 9Cr-oxide dispersion strengthened (ODS) steel was thermally aged at 873 K for up to 5000 h. The size distribution and chemical composition of the dispersed oxide nanoparticles were analyzed by small-angle neutron scattering under a magnetic field. Combined with transmission electron microscopy, Vickers micro-hardness tests and electron backscattered diffraction measurements, all the results showed that the thermal treatment had little or no effect on the size distributions and volume fractions of the oxide nanoparticles in the ferromagnetic matrix, which suggested excellent thermal stability of the 9Cr-ODS steel. 相似文献
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