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关键词： 催化剂性能优化   化工产品纯度   活性   选择性   稳定性  

摘要： 本文深入探讨了化工产品纯度提升过程中催化剂性能优化的重要性、理论基础及实践应用。通过分析催化剂活性、选择性和稳定性的内涵,揭示了催化剂性能与化工产品纯度之间的直接联系。研究采用实验设计与理论模拟相结合的方法,开发了新型高效催化剂,并对其制备工艺、性能测试与评估进行了系统研究。针对催化剂性能优化过程中的难点,提出了相应的策略和实验研究,以及计算模拟的应用,为催化剂性能优化提供了科学指导。最终得出结论,本研究对提升化工产品纯度、推动化工行业可持续发展具有重要意义。

关键词： 水利堤防工程   结构稳定性   优化设计   应力分布  

摘要： 随着运行时间的增加,水体侵蚀给水利堤防造成的影响变得更加显著,若不尽快稳定堤防,将增加堤防出现险情的概率,甚至会溃堤引起洪灾,造成人员伤亡和经济损失。本文从理论基础入手,系统分析了土力学、渗流力学及结构力学对堤防结构稳定性优化设计的支撑作用,并提出了多层次的优化原则与方案。结合应力分布、渗流控制、动态荷载影响、施工方法及生态工程等五个维度,分别设计了针对性措施。分析结果表明,优化设计显著提升了堤防的稳定性和环境适应性。

关键词： 新时期   新能源并网   储能技术   环境效益  

摘要： 随着全球对环境保护和可持续发展的日益重视,新能源技术不断取得突破,对传统能源市场产生了较大的冲击。本文从新能源技术创新的现状与趋势出发,深入剖析其对传统能源市场价格、供需、产业结构等方面的影响,探讨传统能源企业面临的挑战及其应对策略,并进一步阐述新能源技术创新推动经济转型的路径,为能源行业的可持续发展提供理论依据和实践指导。

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： 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： 预见控制   连续时间系统   输入饱和   状态反馈   输出反馈   线性矩阵不等式  

摘要： 本文研究一类带有外部干扰和输入饱和的连续时间系统的预见控制问题.为了能成功地构造出连续时间输入饱和系统的误差系统,与以往对系统方程求导不同,本文利用状态平移方法代替状态求导,使得输入饱和连续时间系统的误差系统的构造成为可能.这样原系统的预见饱和控制就转化为误差系统的标准饱和控制问题.另外,针对原系统的误差系统,分别引入状态反馈和静态输出反馈,并改写输入向量以便利用可预见信号的未来信息.利用Lyapunov函数及LMI技巧,导出了闭环系统渐近稳定的充分条件.最后仿真例子表明了本文结果的有效性.

关键词： 滑坡   稳定性分析   极限平衡法  

摘要： 本文以玉溪市元江县咪哩乡大新村委会大新小组H1滑坡为主要研究对象,通过勘查,结合室内分析斜坡岩土体结构特征,针对H1滑坡地质灾害发生的原因进行重点分析,采用极限平衡法,对滑坡进行定性与定量分析。结果 表明:H1滑坡成因主要受地形较陡、岩土体结构破碎、地质构造和人类工程活动的影响;滑坡为小型浅层推移式土质滑坡,威胁坡体居民生命财产、房屋建筑安全。

关键词： 新能源并网   电力系统   稳定性  

摘要： 新能源并网是当前电力系统发展的重要趋势,但其也给电力系统的稳定性带来了巨大挑战。随着新能源技术的发展,越来越多的可再生能源如风电、太阳能等被接入电力系统,这些新能源的接入对电力系统主网的调度与优化提出了新的挑战。本文分析了新能源接入对电力系统的影响,探讨了新能源接入后电力系统主网调度与优化的策略和方法,包括调度模型的改进、优化算法的应用以及储能技术的利用等。

关键词： 土石坝   渗流   边坡稳定性   数值模拟   优化设计  

摘要： 土石坝工程的渗流与边坡稳定性是水利工程设计和运行中的重要问题。本文以第九师165团莫葫芦水库与卡拉克特调节池工程为研究案例,采用数值模拟技术分析了土石坝渗流场的分布特性及其对边坡稳定性的影响。通过构建数值模型,应用渗流理论和边坡稳定性分析方法,研究了不同工况下的渗流规律和边坡安全系数变化,并提出了优化设计方案。研究表明,通过优化防渗措施和排水系统,能显著提高土石坝的稳定性与安全性。本研究为土石坝工程的设计和维护提供了理论依据和实践指导。

关键词： Profibus-DP   RS485中继器   通信质量  

摘要： 分析润源嘉北污水处理厂Profibus-DP总线通信质量影响因素,通过规范DP总线接头和增加RS485中继器提高网络通信质量,保证现场设备和数据的稳定性。