宇部UM46.4SN立磨矿渣粉生产线的调试经验

介绍了利用立磨粉磨矿渣粉的工艺流程、主机设备和工艺参数,分析了调试过程中上料系统、粉磨系统和成品储存系统出现的问题,并提出了相应的解决方法,总结了立磨生产矿渣粉的经验。     

铸铁机石墨粉尘治理

日照钢铁3号、4号铸铁机除尘系统改造,系统设计风量为500 000 m3/h。本除尘系统采用了移动除尘罩车等关键设备强化收尘效果,以实现既能在不妨碍生产的条件下改善工作环境,又能方便铸铁机铁水溜槽的清理和更换,从而提高铸铁机的工作效率的目的。移动收尘罩车等关键设备的使用,大大改善了铸铁机平台的工作环境,提高了工作效率,降低了劳动强度,消除了安全隐患,同时也产生了一定的经济效益。     

环境给排水系统管理存在问题及策略

加强环境给排水的管理控制要重视进行有规模的预算,要注重科学研究,加强给排水系统管理的规制,全面实现给排水系统管理的实用价值和经济价值。本文分析了环境给排水系统管理存在的问题,并提出了相关的解决对策,为给排水系统的控制管理提供了理论和实践探讨价值。     

“十一五”期间内蒙古海勃湾断面水质状况及变化趋势分析

采用单因子指数、综合污染指数和秩相关系数法对海勃湾断面＂十一五＂期间的水质状况和变化趋势进行了分析。结果表明：海勃湾断面水质基本维持在Ⅲ类水平,部分时段达到Ⅳ类或Ⅴ类;水体水质受到轻污染,水质一般;从历年的变化趋势看,水质呈现不显著好转趋势。     

固体径迹探测器与RAD-7测氡仪测定民用建筑工程室内氡浓度的比较

民用建筑工程室内氡的监测方法很多,其中固体径迹探测器法属于国标方法,RAD-7测氡仪法为近年来引进的仪器监测方法。本文对两种方法进行了比较,包括监测方法及原理、比对试验,并分析了2种方法的相关性、一致性和精度,以及两者在民用建筑工程室内氡验收监测的实际应用中的优缺点等,结果表明:以上两种方法从技术角度上讲,各有优点,均能满足一般室内空气中氡浓度的监测要求,虽然可利用固体径迹探测器法累积测量的结果来估算居住者受照剂量,进而评价氡的辐射危害,但因检验周期(至少30 d)过长,所以不适宜于工程检测;比较而言,RAD-7测氡仪的配置参数和测量方式更适宜于民用建筑工程的室内氡监测,已成为目前监测的主要方法,但在实际监测中,还需注意合理设置足够长的采样时间、湿度控制在10%以下、气路中残留气体的冲洗净化以及当初测值接近或超过《规范》规定的限量值时,有必要进一步延长监测时间进行跟踪监测等事项,以保证监测结果准确可靠。     

循环流水产养殖系统净化研究

文章研究了不同水力停留时间和壳聚糖的投加对循环流水产养殖系统的影响,结果表明,当水力停留时间为8 h,系统内除磷,除氨氮、COD效果明显,通过生物滤池和植物滤池的去除,NO2-浓度下降,植物滤池平均出水浓度总磷1.60 mg/L、氨氮0.016 mg/L、COD为21.788 mg/L;养鱼池投加壳聚糖,出水的色度和浊度都明显降低。     

Analysis of Soil and Water Balance on the Land Arrangement Function

Abstract

The natural supply of land resources is limited, but the economic supply may change along with social and economic development, and its size is decided bye nature and social and economic body conditions. When the supplying ability of land resources threatens the development of society and the conflict between people and land becomes tense, it forced people to improve land utilization and to increase the effective supply of land resources. The paper made an overall consideration on the characteristics of the irrigated farming and the frail ecological environment in Fuhai County, Altay Area, Xinjiang Uigur Autonomous Region and explored land arrangement planning as well as water resource planning and environmental protection. The paper evaluated natural resources, land utilization and water resource of the case study areas and focused on the spatio-temporal balance between the utilization of water and land resources. In the end the paper a feasible plan was made out for the land arrangement project.     

Determinants on Rural-Urban Labor Migration in China: Empirical Analysis on the Effect of Rural Cooperate Medical Insurance based on Cross-Sectional and Longitudinal Data

Abstract

This paper studies factors influencing rural-urban labor migration in China, particularly the implementation of rural cooperative medical insurance (RCMI) in the year 2003. With the support of data analysis from the year 2000, 2004 and 2006, clear linear correlations are found between gender, income, health condition and rural-urban labor flow, whereas the impact of education and employment status are more complicated. More importantly, results from regression show that the establishment of RCMI in countryside of China not only inhibits rural residents from seeking employment outside the village, but also pulls back rural people who have already worked in cities. When regional dimension is concerned, the pure composite effect of RCMI on rural labor flow is less significant in coastal areas with better economic performance and medical service.     

Can imported cold food cause COVID-19 recurrent outbreaks? A review

The coronavirus disease 2019 (COVID-19) pandemic is still spreading all over the world. Although China quickly brought the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) under control in 2020, sporadic outbreaks have recurred from time to time. Outbreaks since June 2020 have suggested that the imported cold food supply chain is a major cause for the recurrence and spread of COVID-19. Here we review recurrent outbreaks in China from June 2020 to March 2021, and we analyse the main causes for recurrence and transmission by the supply of imported cold food from port to fork. Contaminated cold food or food packaging material can transmit the virus through ‘person-to-thing-to-person’, by contrast with the classical ‘person-to-person’ pathway. We decribe safety precautions for the food system, operating environment and people along the cold chain logistics. Surface disinfection and nucleic acid inspection are needed in each stage of the logistics of imported cold food supply.

     

The underground industry of wastewater adulteration: how to trick legal testing with COD removers

Environmental Chemistry Letters - Adulteration is an illegal practice often committed in food and cosmetic industries, yet rarely in environmental regulation compliance. The Chinese Ministry of...