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471.
为评价炼化装置中各控制回路的性能,基于控制回路关键品质指标要求,采用控制回路的设定值、输出值、测量值、控制模式等过程参数设计了准确性指标、稳定性指标及快速性指标等性能评估指标。辅助技术人员在线进行控制回路性能评估,识别性能较差的控制回路,诊断异常原因并进行优化,提高装置的自动化水平。 相似文献
472.
Air sparging (AS) is one of the groundwater remediation techniques for remediating volatile organic compounds (VOCs) in saturated soil. However, in spite of the success of air sparging as a remediation technique for the cleanup of contaminated soils, to date, the fundamental mechanisms or the physics of air flow through porous media is not well understood. In this study, centrifugal modeling tests were performed to investigate air flow rates and the evolution of the zone of influence during the air sparging under various g-levels. The test results show that with the increase in sparging pressure the mass flow rate of the air sparging volume increases. The air mass flow rate increases linearly with the effective sparging pressure ratio, which is the difference between sparging pressure and hydrostatic pressure normalized with respect to the effective overburden pressure at the sparging point. Also the slope of mass flow rate with effective sparging pressure ratio increases with higher g-levels. This variation of the slope of mass flow rate of air sparging volume versus effective sparging pressure ratio, M, is linear with g-level confirming that the air flow through soil for a given effective sparging pressure ratio only depends on the g-level. The test results also show that with increasing sparging pressure, the zone of influence (ZOI), which consists of the width at the tip of the cone or lateral intrusion and the cone angle, will lead to an increase in both lateral intrusion and the cone angle. With a further increase in air injection pressure, the cone angle reaches a constant value while the lateral intrusion becomes the main contributor to the enlargement of the ZOI. However, beyond a certain value of effective sparging pressure ratio, there is no further enlargement of the ZOI. 相似文献
473.
Li Yin-Ming Wei Wen-Ming Hao Jie Gao Peng-Fei Liu Peng-Fei Li Ge-Nan Yang Fei-Hua Wang Zhao-Jia 《Journal of Material Cycles and Waste Management》2022,24(2):618-632
Journal of Material Cycles and Waste Management - Chinese-made chlorine bypass system has been implemented to achieve stable and trouble-free kiln operation using calcium carbide residue (CCR) with... 相似文献
474.
土壤是甲烷(CH4)重要的源和汇.氮沉降和降水格局变化正在急剧改变土壤碳循环,进而可能对土壤CH4通量造成深刻影响.高寒生态系统是巨大的碳库,对氮沉降和降水变化十分敏感.然而,目前多数研究集中在短期实验上,缺乏对长期氮沉降和降水变化背景下CH4通量的响应及其调控因素的认识.以青藏高原高寒草原为研究对象,在2013年搭建模拟氮沉降和降水格局改变实验平台.基于静态箱–气相色谱法测定2020年生长季(5-10月)土壤CH4通量.结果显示,高寒草原土壤呈CH4的汇.氮添加没有显著改变生长季和植物生长高峰CH4通量.然而,降水变化显著改变了生长季和植物生长高峰CH4通量,其中降水增加(+50%降水)降低了CH4的吸收(分别为–16%和–45%),降水减少(–50%降水)增强了CH4的吸收(分别为+73%和+33%).进一步研究发现,与植物属性和功能基因丰度相比,土壤环境因子主导了CH4通量变化(解释率>90%).其中CH4通量与土壤含水量和温度显著正相关,与土壤pH显著负相关.综上所述,在未来全球变化情景下,降水格局改变更能调节青藏高原高寒草原CH4通量的变化.(图6表1参37) 相似文献
475.
Huang Lei Gao Qifeng Fang Hongwei He Guojian Reible Danny Wang Dianchang Wu Xinghua 《Environmental Fluid Mechanics》2022,22(2-3):447-466
Environmental Fluid Mechanics - Nutrient fluxes at the sediment–water interface are essential for water quality and aquatic ecosystems. In this study, a unified expression for the sediment... 相似文献
476.
Tingwei Gao Kang Xiao Jiao Zhang Wenchao Xue Chunhai Wei Xiaoping Zhang Shuai Liang Xiaomao Wang Xia Huang 《Frontiers of Environmental Science & Engineering》2022,16(4):49
477.
Peng Gao Meng Fanchen Ahmed Zahoor Ahmad Mahmood Kurbonov Khayrilla 《Environmental science and pollution research international》2022,29(45):68051-68062
Environmental Science and Pollution Research - Upgrading economic structures and producing less pollution-intensive goods are indispensable for achieving Sustainable Development Goals (SDGs) in... 相似文献
478.
Dong Feng Gao Yujin Li Yangfan Zhu Jiao Hu Mengyue Zhang Xiaoyun 《Environmental science and pollution research international》2022,29(6):8269-8280
Environmental Science and Pollution Research - The European Union (EU) Emissions Trading System is the most important means for the EU to achieve carbon neutrality, but it has been severely... 相似文献
479.
Liu Jiutan Ma Yuanyuan Gao Zongjun Zhang Yuqi Sun Zengbing Sun Tianzhu Fan Haibin Wu Bin Li Mingbo Qian Lili 《Environmental science and pollution research international》2022,29(23):34302-34313
Environmental Science and Pollution Research - The present study, with the aid of GIS, utilizes high-density groundwater (GW) sampling data (1398 samples) to analyze the spatial variation... 相似文献
480.
Zhao Chen Li Chenyu Wang Xiaoming Cao Zhuosong Gao Chao Su Sicong Xue Bin Wang Shang Qiu Zhigang Wang Jingfeng Shen Zhiqiang 《Environmental science and pollution research international》2022,29(29):44148-44161
Environmental Science and Pollution Research - Antibiotic resistance genes (ARGs) have become an important public health problem. In this study, we used metagenomic sequencing to analyze the... 相似文献