白洋淀湿地水质与水生物相关性研究

水质与水生物间关系是湿地生态学的研究热点,研究成果可为湿地水生态修复提供科学依据.在白洋淀湿地设置14个采样点,选取9个水质因子、4类11个水生物指标,利用冗余分析(RDA)方法对其进行研究.结果表明,白洋淀湿地水质和水生物相关性显著,前两个排序轴水质与水生物的相关系数分别为0.973和0.821,特征值分别是0.862和0.059.DO、NO₃^--N、SD、TN和TP是影响水生物的主要水质因子,第一排序轴与NO₃^--N和DO显著正相关;第二排序轴与SD显著正相关,与TN和TP显著负相关.比较可知,NO₃^--N、DO对浮游动植物影响显著,特征值占主要水质因子总特征值的89%;SD、TN和TP对底栖动物及大型水生植物影响大,特征值占主要水质因子总特征值的94%.     

Estimation of Avian Influenza Viruses in Water Environments of Live Poultry Markets in Changsha,China, 2014 to 2018

Food and Environmental Virology - In routine surveillance for avian influenza viruses (AIVs) in the environments of live poultry markets (LPMs), certain samples were positive for AIVs type A while...     

Reuse of Fenton sludge as an iron source for NiFe2O4 synthesis and its application in the Fenton-based process

The potentially hazardous iron-containing sludge from the Fenton process requires proper treatment and disposal, which often results in high treatment cost. In this study, a novel method for the reuse of Fenton sludge as an iron source for the synthesis of nickel ferrite particles(NiFe_2O_4) is proposed. Through a co-precipitation method followed by sintering at 800°C, magnetic NiFe_2O_4 particles were successfully synthesized, which was confirmed by powder X-ray diffraction(XRD), scanning electronic microscopy(SEM), energy dispersive spectroscopy(EDS), Fourier transform infrared spectroscopy(FT-IR) and Raman spectroscopy. The synthesized NiFe_2O_4 could be used as an efficient catalyst in the heterogeneous Fenton process. In phenol degradation with H_2O_2 or NiFe_2O_4 alone, the phenol removal efficiencies within the reaction time of 330 min were as low as 5.9% ± 0.1% and 13.5% ±0.4%, respectively. However, in the presence of both NiFe_2O_4 and H_2O_2, phenol removal efficiency as high as 95% ± 3.4% could be achieved, indicating the excellent catalytic performance of NiFe_2O_4 in the heterogeneous Fenton process. Notably, a rapid electron exchange between_Ni II and_Fe III ions in the NiFe_2O_4 structure could be beneficial for the Fenton reaction. In addition, the magnetic catalyst was relatively stable, highly active and recoverable, and has potential applications in the Fenton process for organic pollutant removal.     

东莞市工业危险废物污染防治对策研究

危险废物具有腐蚀性、毒性、易燃性、反应性和感染性等特性,对公众健康或环境构成重大或潜在的威胁.基于东莞市危险废物产生、处理、处置情况的调查分析,归纳出该市危险废物监管难点和污染防治存在的主要问题,借鉴国内外危险废物管理经验,结合东莞市实际情况,提出危险废物污染防治的对策与建议.建议加强危险废物信息管理系统建设;强化危险废物源头管理;提升处理、处置综合技术能力;发展循环经济,提高资源利用率;加强技术支撑体系建设,提升危险废物监管能力.     

农业作业者的听力防护

农业领域作业者的听力防护问题极少被关注,以农机噪声、养殖场噪声及其对作业者伤害调查数据看,农业噪声对作业者的危害不容忽视,给予作业特点和需求,需要选择合适的听力保护装备,并建立听力保护计划,保护在噪声环境中工作的农业作业者。     

炼油厂周边PAHs污染土壤中微生物群落结构多样性研究

直接从污染土壤中提取微生物基因组DNA,对基因组DNA进行16S rDNA聚合酶链式反应（PCR）扩增和末端限制性片段多态性（T-RFLP）分析,进而对炼油厂附近PAHs污染区土壤微生物群落结构和多样性进行初步研究。结果表明,PAHs浓度较高的土壤中PAHs主要以高相对分子质量PAHs为主,此外,其土壤微生物群落多样性明显低于PAHs浓度较低的土壤。高浓度PAHs刺激了某些土壤微生物生长。不同污染程度的土壤存在一定数量相同的优势菌群,但相对丰度具有明显差异。其中α-变形菌是五个区域土壤中的主导微生物。研究结果将为炼油厂周边土壤的修复治理提供科学依据。     

Prenatal diagnosis of a fetus harboring an intermediate load of the A3243G mtDNA mutation in a maternal carrier diagnosed with MELAS syndrome

We prenatally diagnosed MELAS syndrome in a fetus whose mother and older brother had the MELAS-specific A3243G mutation. The mutant mtDNA level of the amniotic fluid cells was not significantly different from that of the postnatal peripheral blood and hair follicle samples. The obstetrical course was uncomplicated except for transient exacerbation of the mother's diabetes, which required insulin control. At term, the infant was macrosomic, and the delivery was complicated by shoulder dystocia. MELAS syndrome in itself does not influence either the prenatal course of the mother or the fetal outcome. In contrast to the fulminating clinical course of this mother's first child, MELAS symptoms did not develop in her second child until age four, despite similar high tissue levels of mutant mtDNA. The phenotypic diversity in two offspring with similar higher levels of mutant mtDNA suggests that prenatal genetic diagnosis of cultured amniotic cells may yield results that are poor prognosticators of fetal outcome. Copyright © 2004 John Wiley & Sons, Ltd.     

现场总线技术在烟气脱硫控制系统中的应用

阐述了一种将FCS与DCS相结合的控制系统-FDCS，并将其应用在火电厂烟气脱硫过程控制系统中。解决了液位控制易失灵、pH值难控制等问题，提高了系统的稳定性，保证了脱硫效率，降低了综合投资成本。