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1.
This article presents a new design of multiband planar inverted‐F antenna with slotted ground plane and S‐etched slot on the radiation patch. The proposed antenna is optimized using an efficient global hybrid optimization method combining bacterial swarm optimization and Nelder‐Mead (BSO‐NM) algorithm to cover a very important six service bands including GSM900, GPS1575, DCS1800, PCS1900, ISM2450, and 4G5000 MHz with enhanced bandwidths. The BSO‐NM algorithm in Matlab code is linked to the CST Microwave studio software to simulate the antenna. To validate the results, the antenna is analyzed using the finite difference time domain (FDTD) method. A good agreement is achieved between the results of EM simulation and that produced from the FDTD method. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013. 相似文献
2.
《Materials Science & Technology》2013,29(8):980-986
AbstractPolyethylene terephthalate (PET) film drilling using a 248 nm excimer laser through photomask projection is presented. The parameter effects of laser fluence, shot number and repetition rate on the processing results are examined. A high quality microhole array with 50 μm thick PET film is fabricated. When the projection process is carried out, the diameter differences in the microhole in the front and back side of PET are observed. This causes a conical shape in the kerf. The formation of this conical shape in terms of the laser process parameters is discussed. The process parameter effects are investigated and characterised to improve the PET microhole laser machining quality. 相似文献
3.
由于煤矿刮板运输机服役的恶劣环境,对传统NM360耐磨钢的耐蚀及耐磨性能提出了更高的要求。综合考虑合金元素对钢材耐蚀性的提升作用,在传统耐磨钢成分的基础上,采取添加一定量的Cu、Ni合金元素的方法,开发了耐腐蚀NM360钢板。采用场发射扫描电镜,透射电子显微镜以及布氏硬度仪对耐腐蚀NM360钢板的组织及硬度进行分析研究;通过干砂/橡胶轮磨损试验机测试了耐腐蚀NM360钢板的磨损性能;利用腐蚀挂片试验测试了耐腐蚀NM360钢板的腐蚀性能。结果表明,虽然添加Cu、Ni元素后耐腐蚀NM360钢板与传统耐磨钢板硬度相当,但耐腐蚀性能及耐磨性能均有一定程度的提升。 相似文献
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Elena Vargas-Accarino Carlos Herrera-Montvez Santiago Ramn y Cajal Trond Aasen 《International journal of molecular sciences》2021,22(9)
There is an unmet need for simplified in vitro models of malignancy and metastasis that facilitate fast, affordable and scalable gene and compound analysis. “Adherent” cancer cell lines frequently release “free-floating” cells into suspension that are viable and can reattach. This, in a simplistic way, mimics the metastatic process. We compared the gene expression profiles of naturally co-existing populations of floating and adherent cells in SW620 (colon), C33a (cervix) and HeLa (cervix) cancer cells. We found that 1227, 1367 and 1333 genes were at least 2-fold differentially expressed in the respective cell lines, of which 122 were shared among the three cell lines. As proof of principle, we focused on the anti-metastatic gene NM23-H1, which was downregulated both at the RNA and protein level in the floating cell populations of all three cell lines. Knockdown of NM23-H1 significantly increased the number of floating (and viable) cells, whereas overexpression of NM23-H1 significantly reduced the proportion of floating cells. Other potential regulators of these cellular states were identified through pathway analysis, including hypoxia, mTOR (mechanistic target of rapamycin), cell adhesion and cell polarity signal transduction pathways. Hypoxia, a condition linked to malignancy and metastasis, reduced NM23-H1 expression and significantly increased the number of free-floating cells. Inhibition of mTOR or Rho-associated protein kinase (ROCK) significantly increased cell death specifically in the floating and not the adherent cell population. In conclusion, our study suggests that dynamic subpopulations of free-floating and adherent cells is a useful model to screen and identify genes, drugs and pathways that regulate the process of cancer metastasis, such as cell detachment and anoikis. 相似文献
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通过二辊可逆轧机试验研究了45钢、NM360耐磨钢、310S和316不锈钢,初始复层5.1~15.2 mm板和Q345碳素钢初始基层82.7~90.0 mm板(初始复合厚度比5.40%~15.53%)以及总压下量35%~75%对在1150~1000℃热轧的复合钢板复合厚度比的影响。结果表明,当复层板(316和310S钢)变形抗力大于基层板(Q345钢)时,随压下量增加,钢板复合厚度比增加,并且初始复合厚度比越大,热轧后复合厚度比增加越明显;当复层板(45钢和NM360钢)变形抗力小于基层板(Q345钢)时随压下量增加,钢板复合厚度比减小;拟合的复合厚度比相对压下量的变化率Y与强度差Sd的关系式为:Y=(-0.12±0.17)+(0.068±0.004)Sd。 相似文献
8.
采用在Cr-B系中添加微量钒的低成本设计思路来确定NM400耐磨钢的合金成分,详细研究了不同淬火温度和回火温度对NM400耐磨钢显微组织和力学性能的影响,获得了适合工业生产的热处理工艺制度。通过光学显微镜、SEM和TEM观察,分析了经不同温度回火后马氏体组织精细结构的演变规律。结果表明:试验钢具有良好的淬透性,经900~930℃淬火、250℃保温90min回火后得到均匀细小的回火板条马氏体组织;TEM分析表明,回火板条马氏体的宽度在0.1~0.2μm,板条内分布细小均匀的碳化物析出粒子(主要是10~20nm碳氮化钒),提高钢的综合力学性能。 相似文献
9.
基于Web Server(网页服务器)的Web网管的系统架构和实现过程,以Wind Web Server为平台研究了静态路由的配置机制及实现.阐述了嵌入式网管系统的各个部分,并对前端处理模块和后台处理模块进行了分析与具体的实现,最后对静态路由的功能进行了对比性测试.结果表明,基于Web的网管方式在功能上能够与其他网管方... 相似文献
10.
Yidan Zhang Renbing Jia Jing Wang Xiaofang Xu Yuting Yao Shengfan Ge Xianqun Fan 《International journal of molecular sciences》2013,14(7):15092-15104
Uveal melanoma (UM) is the most common primary intraocular malignancy and the leading potentially fatal primary intraocular disease in adults. Melanoma antigen recognized by T-cells (MART-1) has been studied extensively as a clinically important diagnostic marker for melanoma, however, its biological function remains unclear. In the present study, the UM cell line SP6.5, which showed a high level of MART-1 expression, was subjected to small interfering RNA-mediated silencing of MART-1. Silencing of MART-1 expression increased the migration ability of SP6.5 cells and down-regulated the expression of the metastasis suppressor NM23. Our results suggest that MART-1 is a candidate target for the development of therapeutic strategies for UM and in particular for the suppression of metastasis associated with this malignancy. 相似文献