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1.
以应用ProCAST和MAGMAsoft 2款软件为例,针对铸造工艺仿真设计前处理和过程处理每个环节的主要内容与使用方法进行了较为详细地归纳、分析和总结。提出了处理过程的技术路线,并系统地介绍了每项应用内容的操作平台与使用步骤,从而为高效地应用铸造工艺仿真设计提供理论和技术支持。 相似文献
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Evolution of ferronickel particles during the reduction of low-grade saprolitic laterite nickel ore by coal in the temperature range of 900–1250℃with the addition of CaO–CaF2–H3BO3 下载免费PDF全文
The method of producing ferronickel at low temperature(1250–1400℃)has been applied since the 1950s at Nippon Yakin Kogyo,Oheyama Works,Japan.Limestone was used as an additive to adjust the slag composition for lowering the slag melting point.The ferronickel product was recovered by means of a magnetic separator from semi-molten slag and metal after water quenching.To increase the efficiency of magnetic separation,a large particle size of ferronickel is desired.Therefore,in this study,the influences of CaO,CaF2,and H3BO3 additives on the evolution of ferronickel particle at≤1250℃were investigated.The experiments were conducted at 900–1250℃with the addition of CaO,CaF2,and H3BO3.The reduction processes were carried out in a horizontal tube furnace for 2 h under argon atmosphere.At 1250℃,with the CaO addition of 10 wt%of the ore weight,ferronickel particles with size of 20μm were obtained.The ferronickel particle size increased to 165μm by adding 10 wt%CaO and 10 wt%CaF2.The addition of boric acid further increased the ferronickel particle size to 376μm,as shown by the experiments with the addition of 10 wt%CaO,10 wt%CaF2,and 10 wt%H3BO3. 相似文献
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针对高离散精度模型与刀具包围体进行切削计算的情况,由于三维图像重建的计算量大,基于传统CPU实现的数控加工仿真系统不能满足实时性的三维绘制。本文利用GPU的并行性特点,提出并行方式数控仿真切削面显示算法:通过线程并行处理基于MC算法的实体构造模型中体素与刀具包围体的切削计算,根据切削后体素角点信息和边的状态查找建立的构型索引表和交点数目索引表,加速数控仿真切削面的提取,从而提高三维图像的绘制速度,满足实时性显示要求。 相似文献
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景毅 《科技情报开发与经济》2004,14(5):132-133
对处于交变磁场作用下的磁性磨料颗粒的受力和运动规律进行了分析和描述,为交变磁场作用下的磁粒研磨光整加工技术提供了新的思路和工艺选择。 相似文献
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介绍了AWM720P1新型气体流量传感器的工作原理、性能、特点.针对呼吸机的工作特点,分析了IPPV的流速模型、流速的测量方法、传感器的校正数据处理方法. 相似文献
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详细地讲解Excellink宏的建立、使用方法及宏函数用法 ,连接MicrosoftExcel和MATLAB的步骤及在Excel中应用MATLAB的方法 ,极大地增强了Excel处理数据的能力和图形输出的能力 ,并用两个实例验证了这个Excellink宏在数据分析过程中所显示的优越性。 相似文献
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Science Letters: A synthetic Toll-like receptor 2 ligand decreases allergic immune responses in a mouse rhinitis model sensitized to mite allergen 下载免费PDF全文
It has been proposed that activation of Toll-like receptors (TLRs) plays crucial roles in the polarization of adaptive immune responses. A synthetic Toll-like receptor 2 (TLR2) ligand, Pam3CSK4, has been reported to modulate the balance of Th1/Th2 responses. We evaluated the modulation effect of Pam3CSK4 on allergic immune response in a mouse rhinitis model sensitized to house dust mite allergen (HDM). Mice were sensitized and challenged with Dermatophagoidesfarinae allergen (Der f), and then the allergic mice were treated by Pam3CSK4. Nasal allergic symptoms and eosinophils were scored. Der f-specific cytokine responses were examined in the splenocytes and bronchoalveolar lavage fluid (BALF). Serum level of total IgE was also detected. After establishing a mouse allergic rhinitis model with HDM, we have showed that Pam3CSK4 treatment not only ameliorated the nasal allergic symptoms remarkably but also decreased the eosinophils and total inflammation cells in BALF significantly. Analysis of cytokine profile found that IFN-7 released from either BALF or stimulated splenocytes increased markedly in Pam3CSK4-treated mice, while IL-13 decreased significantly. Moreover, serum level of total IgE was significantly lower in Pam3CSK4-treated mice than in the untreated. Thus, in an allergic rhinitis mouse model developed with HDM, Pam3CSK4 was shown to exhibit an antiallergic effect, indicating its potential application in allergic diseases. 相似文献
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