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611.
针对目前国内健康管理存在健康信息采集来源狭窄、健康指标数据利用效率低、信息化水平和功能与用户及社会发展不匹配等问题,设计开发了基于"互联网+"的海外油田员工健康管理信息化平台。通过运用互联网技术,使健康管理更加快捷化、流程化和规范化,实现了员工出国前健康体检、出国前健康评估和出国后健康监测的全业务流程在线管控,同时系统自动采集体检报告,形成完整的员工健康档案,提升了员工健康管理水平,为海外油田员工体检套餐优化、重点疾病防控和出国健康评估等提供了全面的数据决策依据。  相似文献   
612.
This study aims to investigate the effects of UV-C irradiation on photosynthetic processes of Microcystis aeruginosa to unravel the mechanism(s) involved in how and in what ways UV-C mediates growth suppression and cellular recovery. Changes in the concentration of photosynthetic pigments, photochemical efficiency, PS II core protein (D1) content, and the coding genes expressions were measured. The results indicate that UV-C doses at 20–200 mJ cm−2 lead to rapid reduction in gene expression of both psbA (for D1) and cpc (for phycocyanin), but the suppression was short term and recoverable within 3 d of post-UV incubation. Conversely, UV-C doses at ?50 mJ cm−2 could induce marked decline in photochemical efficiency (represented by the optimal PS II quantum yield, FV/FM, and the effective PS II quantum yield, Y) as well as decreases in D1 content and water soluble pigments (phycoerythrins, phycocyanins, allophycocyanins) in M. aeruginosa during the post UV-C incubation period. The results suggest that interruption of both the light energy harvesting apparatus (especially the water soluble pigments) and the photochemical process mainly accounted for the growth suppression effect in UV-C irradiated M. aeruginosa.  相似文献   
613.
The removal of estrogenic chemicals during wastewater reclamation has been a great concern. Current advanced treatment processes are inefficient for the removal of estrogenic chemicals from secondary effluents of municipal wastewater treatment plants (WWTPs) due to the coexistence of other pollutants with less environmental significance which are also removed simultaneously. The search for highly selective and low-cost removal methods is warranted. Therefore, surface-molecular-imprinted polymer-modified TiO2 nanotube (S-MIP-TiO2 NT) photocatalysts were fabricated, characterized, and tested for the removal of estrogenic pollutants from wastewater in this study for the first time. Scanning electron microscopy and Fourier-transform infrared spectroscopy studies showed that the TiO2 NTs (with an average diameter of 60 nm) were successfully imprinted with functional groups (i.e., carboxyl). The adsorption selectivity and photocatalytic activity of the S-MIP-TiO2 NTs towards template compound (17β-estradiol, E2) were improved, compared with neat TiO2 NTs. Interestingly, S-MIP-TiO2 NTs exhibited higher adsorption intensity and photocatalytic selectivity at low concentrations (from 10 ng/L to 100 μg/L, as normal estrogenic chemical concentrations in secondary effluents) of E2 than that at high concentrations (from 10 to 1,000 mg/L). It was also found that some representative estrogenic chemicals and estrogenic activity could be selectively and rapidly removed from secondary effluents of municipal wastewater treatment plants using S-MIP-TiO2 NTs as photocatalysts. In addition, S-MIP-TiO2 NT photocatalysts exhibited excellent regeneration characteristics. Photocatalytic treatment using S-MIP-TiO2 NTs could be a promising approach for the effective removal of estrogenic chemicals from secondary effluents of municipal WWTPs.  相似文献   
614.
对新疆某油区的土壤污染状况进行研究,以期为石油开采区土壤生态环境保护与治理提供基础资料。通过对新疆某油区内的土壤环境状况调查发现,油田开发过程中产生的钻井废水、原油脱出水、井下作业废水、钻井废弃泥浆、钻井岩屑、污水处理厂污泥、罐底油泥是土壤污染的重要来源;该油区土壤受油田开发活动的影响,石油类、铬、总盐的含量升高,土壤有机质含量降低,pH趋于弱酸性。油气田开发项目应加强对污染物的管理,及时完善环保措施,并建立有效的环境管理制度,将油气田开发活动对环境的影响降到最低。  相似文献   
615.
通过水合、萃取、水洗等操作工艺对N系列催化剂生产过程中产生的含P含Ti高沸物进行处理。用去离子水回收含P含Ti高沸物中的TiCl4,形成TiCl4水溶液;采用萃取剂S(一种醇类物质)对TiCl4水溶液进行萃取净化;三次萃取后TiCl4水溶液中的ρ(P)和ρ(Mg)均小于50mg/L,达到厂家优级品要求。采用新工艺对含P含Ti高沸物进行无害化处理,与原工艺比较,每生产1t催化剂,可节省质量分数为40%的液碱约15t,减少废渣13t左右,减少废水20t以上。  相似文献   
616.
采用活性炭吸附、溶剂解吸和气-质联用(GC-MS)分析的方法,对柴油机尾气中芳香烃污染物进行了定性、定量分析。实验结果表明,该方法能够减少柴油机尾气中其他颗粒相和气相有机成分的干扰,采样快速,灵敏度、准确度高;活性炭吸附管采样效率高,当采样流量为4 L/min、采集时间20 min时,不会出现芳香烃脱附现象;测量方法重复性较好,相对标准偏差低于6.5%,检出限为3~9μg/m3,回收率为87.5%~95.2%;该方法可用于测量柴油机燃用生物柴油和0号柴油尾气中芳香烃污染物。  相似文献   
617.
The structurally related hydroxylated polybrominated diphenyl ether (PBDE) like hydroxylated 4,4′-dibromodiphenyl ether widely occur in precipitation, surface water, and biotic media. The origins of hydroxylated PBDEs (OH-PBDEs) are of particular interest due to their greater toxic potencies than the corresponding PBDEs. We studied the transformation behavior and products of 4,4′-dibromodiphenyl ether (BDE 15) mediated by lignin peroxidase (LiP), an extracellular enzyme that is produced by certain white rot fungus and is widely present in the natural environment. We found that BDE 15 can be effectively transformed through the reaction mediated by LiP, and two different mono-OH-dibromodiphenyl ethers were identified by using gas chromatography–mass spectrometry (GC-MS) and GC-MS/MS. In particular, we compared the reaction behavior for systems variously containing natural organic matter (NOM) and/or veratryl alcohol (VA), a metabolite that certain fungus produces along with LiP in nature. It was found that the VA’s enhancement effect on LiP performance was impaired by the presence of NOM. The findings in this study provide useful information for better understanding the origins of OH-PBDEs found in the environment.  相似文献   
618.
针对深圳某一路段使用美国Lansmont公司开发的SAVER环境应力记录仪记录汽车运输过程中的环境应力,利用相关处理软件整理分析数据,最后在实验室中的通过电磁振动台的随机振动模式来进行模拟重现从而实现“Field to lab”.该方法用短时间的实验室内试验来代替长时间的实际运输过程,不仅绿色环保,而且省时省力,是一种值得推广的试验方法.  相似文献   
619.
Polycyclic aromatic hydrocarbons (PAHs) have been detected in some commercial teas around the world and pose a threat to tea consumers. However, green tea polyphenols (GTP) possess remarkable antioxidant and anticancer effects. In this study, the potential of GTP to block the toxicity of the model PAH phenanthrene was examined in human embryo lung fibroblast cell line HFL-I. Both GTP and phenanthrene treatment individually caused dose-dependent inhibition of cell growth. A full factorial design experiment demonstrated that the interaction of phenanthrene and GTP significantly reduced growth inhibition. Using the median effect method showed that phenanthrene and GTP were antagonistic when the inhibitory levels were less than about 50%. Apoptosis and cell cycle detection suggested that only phenanthrene affected cell cycle significantly and caused cell death; GTP lowered the mortality of HFL-I cells exposed to phenanthrene; However, GTP did not affect modulation of the cell cycle by phenanthrene.  相似文献   
620.

Materials and methods  

The levels and possible sources of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface sediments of Liaodong Bay, Bohai Sea, China.  相似文献   
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