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991.
基于电子垃圾绿色、高效的分离回收需求,利用barracuda仿真软件建立电子垃圾颗粒气固分离模型,模拟电子垃圾颗粒在气流作用下的分选特性,探讨在不同气流参数及不同物料流量、不同粒径下电子垃圾各组分颗粒的分离效率和回收率。研究表明,电子垃圾颗粒下落流量与粒径对贵金属回收分离有显著影响,当一次进风的气流速度为3.8m/s、二次进风的气流速度为4.6m/s、入料开口宽度为4mm,颗粒粒径为75~100um时,Au的品位率和回收可达87.1%和99.1%,Cu的品位为70.8%,回收率为85.8%。说明在二次进风的作用下,改变电子垃圾流量和控制粒径大小可以有效提升电子垃圾中贵金属的品位和回收率,同时对多密度颗粒的分选提供参考和借鉴。 相似文献
992.
详细地介绍了中密度纤维板干燥前与干燥后组合施胶系统技术原理、技术优势及其在生产线上的实际应用,详细地分析了应用过程存在的主要问题及其产生原因,并对其后续使用提出了建议. 相似文献
993.
Shun Guo Rui-Tang Wu Yu-Lu Shi Yan-Pin Hou Wen Ma Guang-Lei Liu Hai-Xia Liu Xiao-Nong Cheng 《稀有金属(英文版)》2021,(3):600-606
The deformation behavior involved in Nb/NiTi composite for biomedical applications within a large macroscopic strain range was investigated by tensile loading-unloading test and in situ synchrotron X-ray diffraction(SXRD).Experimental results show that during loading,the Nb/NiTi composite experiences the elastic elongation of B2-NiTi austenitic,B19'-NiTi martensitic and β-Nb phases,B2→ B19' stress-induced martensitic(SIM) transformation and tensile plastic deformation of β-Nb phase.During unloading,the deformation behavior involved in Nb/NiTi composite includes the elastic recovery of B2-NiTi austenitic,B19'-NiTi martensitic and β-Nb phases,reverse phase transformation B19'→B2 and compressive deformation of p-Nb phase.The martensitic transformation in this composite is almost reversible and occurs in a localized manner.These results might contribute to a comprehensive understanding of the deformation mechanism involved in Nb/NiTi composite and shed some light on design and development of novel composites with a combination of good biocompatibility and excellent superelasticity for biomedical applications. 相似文献
994.
模态分析是水电机组故障诊断的重要方法,但其传统方法缺少对接触部分非线性接触的模拟手段,直接影响模态分析的准确性,也无法对链接部位的失效过程及趋势进行分析。该文基于用户自定义单元子程序接口(user-defined element subroutine interface,UEL),建立了结合部三维非线性专用分析单元模型。推导所提模型有限元格式的基本方程,获得表征材料非线性特性的本构关系;给出螺栓连接的固定结合部的静态分析,以及立式水轮发电机导轴承支架的模态分析算例;给出导轴承支架的支臂末端螺栓连接变刚度计算的工程应用实例。实验与仿真对比结果表明了建立的UEL三维非线性接触分析专用单元模型的正确性;连接失效分析表明了随着导轴承支架接触刚度的下降,会在整机模态频率计算中引入新的频率段这一结果的重要性。 相似文献
995.
Xuejing Zhu Dan Gao Vittorio Albertazzi Jianyong Zhong Li-Jun Ma Liping Du Yu Shyr Valentina Kon Hai-Chun Yang Agnes B. Fogo 《International journal of molecular sciences》2022,23(11)
We previously found that short-term treatment (week 8 to 12 after injury) with high-dose angiotensin receptor blocker (ARB) induced the regression of existing glomerulosclerosis in 5/6 nephrectomy rats. We therefore assessed the effects of long-term intervention with ARB vs. nonspecific antihypertensives in this study. Adult rats underwent 5/6 nephrectomy and renal biopsy 8 weeks later. The rats were then divided into three groups with equivalent renal function and glomerular sclerosis and treated with high-dose losartan (ARB), nonspecific antihypertensive triple-therapy (TRX), or left untreated (Control) until week 30. We found that blood pressure, serum creatinine levels, and glomerulosclerosis were lower at sacrifice in ARB and TRX vs. Control. Only ARB reduced proteinuria and maintained the density of WT-1-positive podocytes. Glomerular tufts showed more double-positive cells for CD44, a marker of activated parietal epithelial cells, and synaptopodin after ARB vs. TRX or Control. ARB treatment reduced aldosterone levels. ARB-treated rats had significantly improved survival when compared with TRX or Control. We conclude that both long-term ARB and triple-therapy ameliorate progression, but do not sustain the regression of glomerulosclerosis. ARB resulted in the superior preservation of podocyte integrity and decreased proteinuria and aldosterone, linked to increased survival in the uremic environment. 相似文献
996.
金属加工液作为机械加工过程中必不可少的部分和影响环境能源以及劳动者身体健康的重要因素而一直受到人们的关注。新型环保型金属加工液无庸置疑地成为了金属加工液研究方向上的未来趋势。 相似文献
997.
998.
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1000.
Yongjie Liu Dan Li Shengquan Zhang Liping Zhang Jie Gong Yanhong Li Jiamin Chen Fengting Zhang Xiangzheng Liao Zhaobo Chen Yongbo Wang Binshuang Pang Jinxiu Ma Xianchao Chen Jiangang Gao Changping Zhao Shiqing Gao 《International journal of molecular sciences》2022,23(15)
Temperature-sensitive genic male sterile (TGMS) line Beijing Sterility 366 (BS366) has been utilized in hybrid breeding for a long time, but the molecular mechanism underlying male sterility remains unclear. Expression arrays, small RNA, and degradome sequencing were used in this study to explore the potential role of miRNA in the cold-induced male sterility of BS366. Microspore observation showed defective cell plates in dyads and tetrads and shrunken microspores at the vacuolated stage. Differential regulation of Golgi vesicle transport, phragmoplast formation, sporopollenin biosynthesis, pollen exine formation, and lipid metabolism were observed between cold and control conditions. Pollen development was significantly represented in the 352 antagonistic miRNA-target pairs in the integrated analysis of miRNA and mRNA profiles. The specific cleavage of ARF17 and TIR1 by miR160 and miR393 were found in the cold-treated BS366 degradome, respectively. Thus, the cold-mediated miRNAs impaired cell plate formation through repression of Golgi vesicle transport and phragmoplast formation. The repressed expression of ARF17 and TIR1 impaired pollen exine formation. The results of this study will contribute to our understanding of the roles of miRNAs in male sterility in wheat. 相似文献