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关键词： 化学机械抛光   氧化铈纳米颗粒   悬浮稳定性   N-乙酰-D-脯氨酸   表面改性  

摘要： 随着半导体行业的快速发展,对可使其全局平坦化的化学机械抛光(CMP)技术提出更高的要求。因此,发明一种更安全、更稳定、更高效且更环保的氧化铈抛光液迫在眉睫。本研究通过溶剂水热法,利用N-乙酰-D-脯氨酸(ADPO)对氧化铈纳米磨料进行表面改性,使用XRD、热重分析、N2吸附–脱附、DLS、TEM等多种手段对改性前后的氧化铈纳米颗粒分析对比。研究表明,改性后的氧化铈悬浮液可稳定悬浮30天以上。本研究探讨了改性前后氧化铈纳米磨料的CMP性能,采用膜厚测量仪测量改性前后纳米磨料的材料去除率,发现表面改性可使氧化铈纳米磨料的材料去除率降低14%。借助原子力显微镜对CMP后的晶圆表面质量进行表征计算,改性前氧化铈纳米磨料抛光的Ra和Rq值分别为0.240 nm、0.329 nm,改性后氧化铈纳米磨料抛光的Ra和Rq值分别为0.186 nm、0.236 nm,表面质量获得了显著提高。With the rapid development of the semiconductor industry, it is inevitable that higher requirements for chemical mechanical polishing (CMP) technology will be put forward, which can make it globally flat. Therefore, it is urgent to invent safer, more stable, more efficient, and more environmentally friendly cerium oxide polishing slurries. In this study, the surface modification of cerium oxide nanoparticles was carried out using N-Acetyl-D-Proline (ADPO) using a solvent hydrothermal method. The cerium oxide nanoparticles before and after modification were analyzed and compared using XRD, thermogravimetric analysis, N2 adsorption-desorption, DLS, TEM, and other means. The results show that the modified cerium oxide suspension can be stably suspended for more than 30 days. In this study, the CMP properties of cerium oxide nano-abrasive before and after modification were investigated. The material removal rate of cerium oxide nano-abrasive before and after modification was measured by using a film thickness measuring instrument. It was found that the material removal rate of cerium oxide nano-abrasive was reduced by 14% by surface modification. The surface quality of the wafer after CMP was characterized and calculated by atomic force microscopy. The Ra and Rq values of ceria nano-abrasives polishing before modification were 0.240 nm and 0.329 nm, respectively, and the Ra and Rq values of ceria nano-abrasives polishing after modification were 0.186 nm and 0.236 nm, respectively, which significantly improved the surface quality.

关键词： RTK技术   高精度测绘   误差分析   改进策略   定位问题  

摘要： 实时动态差分定位技术(RTK),在高精度测绘领域,起到了不小的作用。但在许多实际情况下,RTK技术的精度往往会受到各种误差因素的影响。于是,本研究对这些主要的影响RTK技术精度的误差因素,做了详尽的深入分析,其中涉及卫星钟差误差、大气层延迟误差、多路径效应误差以及观测噪声等问题。为处理这些误差因素,研究者们提出了数个优化的策略。这些策略在实际中采用后,使RTK技术的测绘精度有了明显的进步。一番试验数据显示,改进后的RTK技术,其水平精度和垂直精度分别提升了10%和15%。既解决了RTK技术在长距离、复杂环境下的定位问题。对此研究成果,给予了RTK技术在运用到高精度测绘领域时,理论上的指导和实际上的改良建议。

关键词： 智能   滴灌   水肥一体化   优良苗木  

摘要： 随着现代农业的发展,智能滴灌水肥一体化栽培技术成为提高农作物产量和质量的重要手段。然而由于苗圃地的特殊性,该技术在苗木培育上的应用并不多。基于肥城市苗圃智能滴灌水肥一体化栽培技术体系推广与示范项目建设,总结了苗圃地智能滴灌水肥一体化栽培技术体系设计、安装、运行、维护。

关键词： 地下工程   贯通测量   贯通点误差   附加约束条件的间接平差   最小二乘原则  

摘要： 为了提高地下工程贯通点的精度,采用附加约束条件的间接平差方法,即在平差时增加一个约束条件,使得地面控制网点对于贯通点的横、纵两项误差的比例相等,利用最小二乘法对地面控制网进行平差处理,求得地面控制网点平差后的坐标值,并将此方法应用于实例中。结果表明,附加约束平差后控制点的坐标发生了变化,变化后控制点对贯通点的定位精度提高了20%,以此确保地下贯通工程的质量与安全。

关键词： 跨声速压气机叶片   扭转角误差   主成分分析   非嵌入式混沌多项式   不确定性量化  

摘要： 为了研究全局叶型扭转角误差对跨声速压气机叶片性能参数及流场结构的影响,以Rotor37为研究对象提出了一种不确定性量化流程及方法。首先基于主成分分析方法构建几何不确定性三维降阶模型,然后基于非嵌入式混沌多项式中三维正态分布变量的选取方法,用数值方法求解需求样本点上的全三维Reynolds-averaged Navier-Stokes方程以构建非嵌入式混沌多项式,借以评估大样本量下的性能响应,结果显示性能参数的统计结果服从正态分布,其平均水平不受影响,但存在约1%的波动。利用Spearman相关性分析得到影响流场的关键展向截面位置,结果表明效率与70%~100%叶高范围内的扭转角误差负相关性最强,加工时应着重提高此区域的加工精度。通过分析统计学意义下流场的波动情况和具有极端效率叶型的流场特征以探究扭转角误差对性能的影响机理,结果表明在间隙泄漏流与激波位置处的流场波动程度最剧烈,扭转角误差通过影响激波位置与泄漏流强度从而影响二者的相互干扰作用,继而影响下游的堵塞程度,最终对效率产生影响。由此可见,全局扭转角误差对叶片性能及流场的影响已不容忽视,在稳健性设计中应根据流场特征着重考虑。

关键词： Rice–rape rotation   Soil enzyme activity   Soil organic carbon   Soil organic carbon fraction   Stability of soil organic carbon pool  

摘要： 【Objective】Rape multiple-cropping is an important planting mode to promote grain stabilization and rapeseed increase in South China rice growing area. We explored the influence of soil organic carbon (SOC) accumulation and its stability characteristics under different rice–rape rotation measures with whole-straw returning, which is of great significance for in-depth analysis of soil carbon cycle in paddy fields by making full use of winter fallow fields to plant rape. 【Method】This study is based on an 8-year yield localization experiment. In contrast with rice–rice–winter fallow, we explored the characteristics of SOC and its fraction accumulation under three rice–rape rotation treatments: rice–rice–rape, rice–rape tillage, and rice–rape no tillage. 【Result】The results indicated that the content of SOC in 0–20 cm soil layer was increased by 5.28%–25.12% under the three rice–rape rotation treatments, especially under the rice–rice–rape treatment. Also, the increasing rate of SOC in 20–40 cm soil layer was 18.48%–43.97%, among which the rice–rape tillage and the rice–rape no tillage treatment reached a significant level. Except for rice–rape tillage treatment in 0–20 cm soil layer, the content of mineral-associated organic carbon (MAOC) from all the rice–rape rotation measures was increased significantly in different soil layers. At the same time, the ratio of particulate organic carbon (POC) to SOC was significantly decreased while the ratio of MAOC to SOC increased in each treatment from both 0–20 cm and 20–40 cm soil layer. The increasing rate of MAOC/SOC were 2.31%–7.49% and 1.56 %–2.66% in the two soil layers, respectively. Possible causes of these results may be that rice–rape rotation increased the activity of organic carbon invertase enzyme (β-glucosidase、β-1, 4-glucanase and Laccase) as well as microbial biomass carbon in 0–20 cm soil layer to varying degrees, thereby promoting the conversion of POC to MAOC. 【Conclusion】In summary, rape multiple-cropping in w

关键词： 机器视觉   边缘检测   双三次插值   滞后双阈值二值化   Canny-Devernay算法   亚像素  

摘要： 为满足机器视觉精密尺寸测量对图像边缘深亚像素级定位和强抗噪能力的要求,提出了基于双三次插值的Canny-Devernay亚像素图像边缘检测算法。首先,采用中值滤波降低采集图像噪声;其次,通过双三次插值细分图像边缘;然后,运用最大化类间方差(Ostu)算法优化Canny-Devernay算法参数并改进轮廓生成步骤,精确提取亚像素边缘;最后基于高分辨率工业相机和高性能计算机构建实验系统,分别以OpenCV图像、USB接口插件采集图像为对象进行实验。实验结果表明,在相机标定精度为0.0098毫米/像素的情况下,该算法边缘检测平均误差为0.00685 mm,小于0.7像素,计算耗时偏差为7.68‰,其边缘定位精度、抗噪能力和算法稳定性均优于Canny算法、基于Zernike矩的算法以及Canny-Devernay算法,将用于研制某新型精密机器视觉尺寸测量设备。

关键词： 水利水电工程   堤防护岸工程   施工技术  

摘要： 随着我国基础设施建设迅速发展,水利水电行业已经成为推动经济发展的关键力量。其中,作为维护河流安全、避免水患灾害关键措施的护岸堤防工程,其在整个水利建设体系中占据了重要地位。该工程涵盖了广袤的区域,为江河岸线提供了保护。本文在分析具体案例的基础上,着重讨论了水利水电建设中护岸堤防施工的核心技术要点,旨在为相关人员工作提供参考。

关键词： 厌氧氨   氧化工艺   污水处理  

摘要： 厌氧氨氧化工艺是当前城市运营中常见的高效污水处理技术,其应用能够有效去除污水中的氨氮等污染物,有助于改善水质,降低废水对环境产生的负面影响。为了进一步发挥厌氧氨氧化工艺在污水处理中的应用效果,文章首先对厌氧氨氧化工艺的反应原理、影响因素进行分析,然后以印染污水为研究对象,分析该技术在污水处理中的应用工艺要点和应用效果。

关键词： 煤矿开采   采煤工艺   综采工艺   一次采全高  

摘要： 随着工业化进程的加快,对煤炭资源的需求是越来越多,为了更好满足市场对煤炭资源的需要,应加大煤炭资源开采强度。在煤炭开采过程中,一次采全高的综合机械化开采技术作为一种先进的采煤方法,能够显著优化开采作业条件,并大幅提升煤炭的开采效率,所以需要加强对一次采全高综采采煤工艺的研究。本文主要对一次采全高综采采煤工艺应用要点和发展趋势进行了分析,希望可以为煤矿行业的可持续发展提供指导和支持。