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591.
总结了涪陵页岩气田开发初期钻井岩屑采用固化填埋方式处置存在占地面积大且易产生二次污染隐患等问题,因地制宜地探索钻井岩屑的资源化利用。分析了水基岩屑随钻预处理和油基岩屑热脱附技术,结合钻井岩屑的理化性质,开展了水基岩屑脱水后干渣制路基材料、制砖及水泥窑协同处置,油基岩屑灰渣制混凝土、制砖及水泥窑协同处置的探索和实践,基于环境安全、技术稳定可靠、消纳量大的原则,最终形成了涪陵页岩气田钻井岩屑资源化方案:水基岩屑"随钻预处理、水泥窑协同处置",油基岩屑"热脱附、水泥窑协同处置",实现了钻井岩屑的资源化综合利用。 相似文献
592.
文章明确了挥发性油藏天然气回注井控的安全环保关键因素;量化了低渗挥发性油藏天然气回注注入能力,确定注入端各节点安全生产压力分布,攻关相关配套工艺设备,实现安全有效注入;开展室内实验和PVT相态拟合,分析注天然气后天然气和原油性质变化规律,创新非混相驱组分数值模拟参数优化方法,开展带人工压裂裂缝的组分数值模拟,精准确定压力场分布,降低计量及监测不准带来的安全隐患;明确注气井气窜影响因素,优化注采参数,抑制油井气窜,降低生产风险,实现井控安全情况下的天然气驱环保高效开发。 相似文献
593.
In this research, epigenetic effects of bisphenol A (BPA) on human breast cancer MCF-7 cells were analyzed. Genome-wide DNA methylation and gene expression were analyzed in MCF-7 cells exposed to BPA (10?5 and 10?6 mol/L for 5 weeks). No significant changes in the global level of 5-methyl-2′-deoxycytidine and 5-hydroxymethyl-2′-deoxycytidine were observed. DNA methylation profiling analysis indicated that BPA exposure resulted in the hypermethylation of FOXK2, LKB1, LMX1A and CUGBP2 and the hypomethylation of PTPRN2, TRIM27, BCAS3 and ZNF423. Decreased expression of apoptosis genes (P38 and BCL2L1) and increased expression of chemokine (Cxcl2 and ccl20) were detected. Changes of these genes were speculated to affect the ERα-related cell growth as well as cell apoptosis. 相似文献
594.
Bifenthrin is a chiral synthetic pyrethroid insecticide that has been commonly used for agricultural and domestic pest control over the past decades. Due to its widespread application, residues of bifenthrin has been frequently detected in environmental media, residential areas and biota, thus posing potential risks to the health of wildlife and humans. In particular, bifenthrin exhibits high acute lethal toxicity to aquatic species, and it is the primary contributor to the toxicity of insecticides in waters. Additionally, bifenthrin can also cause sublethal toxic effects on various non-target organisms, including developmental toxicity, neurobehavioral toxicity, oxidative damage, immune toxicity and endocrine disrupting effects. Here we review recent studies about the fate of bifenthrin in the environment and biological systems, the toxicity of the chiral parent compound bifenthrin and the toxic effects of main metabolites. The adverse effects of bifenthrin, identified from both in vitro and in vivo studies, and the potential underlying mechanisms are presented. We discuss the enantiomeric difference in the toxicological effects of bifenthrin, since enantiomers of chiral compounds show different interactions with biological systems. Pyrethroid insecticides metabolites are not acutely toxic, but they have sublethal toxicity, such as endocrine disrupting effects and immunotoxicity. We provide emerging evidence for toxic effects of several main metabolites. 相似文献
595.
Yonggang Xue Xiaoping Wang Ping Gong Tandong Yao 《Environmental geochemistry and health》2018,40(5):1941-1953
PAHs could be transported to Tibetan Plateau in accompany with atmospheric circulation. The forest regions were found be an important sink for PAHs, while their distributions and migrations in forest are still uncertain. In this study, soil profile samples were collected in southeastern Tibet and the concentrations, distributions, and migration of PAHs in forest region were investigated. The PAHs levels in the forest soils were at the low end of remote sites, ranged from 27.4 to 120.3 ng g?1 on a dry weight based. Due to low ambient temperature and high organic carbon content, enrichment of PAHs was found in higher altitude on north side. According to the soil profiles, the vertical distributions of PAHs in organic layers were mainly influenced by pedogenesis, while the vertical distributions in mineral layers were dominated by downward leaching effect. Enrich factor (EF) of PAHs was estimated, and the values in organic layers were positively correlated with the octanol–air partition coefficients (K OA), but EFs in mineral layers decreased with the K OA values. PAHs in the surface soils on the north side of forest were relatively stable, while the migration of PAHs on the south sides and other clearing sites was more active. The leaching rates of PAHs in clearing site ranged between 1.42 and 29.3%. The results from this study are valuable on the characterization of PAHs in Tibetan Plateau. 相似文献
596.
Zhiguo Cao Qiaoying Chen Xiaoying Wang Yajie Zhang Shihua Wang Mengmeng Wang Leicheng Zhao Guangxuan Yan Xin Zhang Ziyang Zhang Tianfang Yang Mohai Shen Jianhui Sun 《Environmental geochemistry and health》2018,40(6):2441-2452
Concentrations of eight trace metals (TMs) in road dust (RD) (particles?<?25 μm) from urban areas of Xinxiang, China, were determined by inductively coupled plasma mass spectrometry. The geometric mean concentrations of Zn, Mn, Pb, As, Cu, Cr, Ni and Cd were 489, 350, 114, 101, 60.0, 39.7, 31.6, and 5.1 mg kg?1, respectively. When compared with TM levels in background soil, the samples generally display elevated TM concentrations, except for Cr and Mn, and for Cd the enrichment value was 69.6. Spatial variations indicated TMs in RD from park path would have similar sources with main roads, collector streets and bypasses. Average daily exposure doses of the studied TMs were about three orders of magnitude higher for hand-to-mouth ingestion than dermal contact, and the exposure doses for children were 9.33 times higher than that for adults. The decreasing trend of calculated hazard indexes (HI) for the eight elements was As?>?Pb?>?Cr?>?Mn?>?Cd?>?Zn?>?Ni?>?Cu for both children and adults. 相似文献
597.
Maocong Hu Yin Liu Zhenhua Yao Liping Ma Xianqin Wang 《Frontiers of Environmental Science & Engineering》2018,12(1):3
Treating water contaminants via heterogeneously catalyzed reduction reaction is a subject of growing interest due to its good activity and superior selectivity compared to conventional technology, yielding products that are non-toxic or substantially less toxic. This article reviews the application of catalytic reduction as a progressive approach to treat different types of contaminants in water, which covers hydrodehalogenation for wastewater treatment and hydrogenation of nitrate/nitrite for groundwater remediation. For hydrodehalogenation, an overview of the existing treatment technologies is provided with an assessment of the advantages of catalytic reduction over the conventional methodologies. Catalyst design for feasible catalytic reactions is considered with a critical analysis of the pertinent literature. For hydrogenation, hydrogenation of nitrate/nitrite contaminants in water is mainly focused. Several important nitrate reduction catalysts are discussed relating to their preparation method and catalytic performance. In addition, novel approach of catalytic reduction using in situ synthesized H2 evolved from water splitting reaction is illustrated. Finally, the challenges and perspective for the extensive application of catalytic reduction technology in water treatment are discussed. This review provides key information to our community to apply catalytic reduction approach for water treatment.
相似文献
598.
Xiangqun Chi Yingying Zhang Daosheng Wang Feihua Wang Wei Liang 《Frontiers of Environmental Science & Engineering》2018,12(1):11
The feasibility of using Phragmites australis-JS45 system in removing nitrobenzene from sediments was conducted. However, it was observed that nitrobenzene degraded rapidly and was removed completely within 20 days in native sediments, raising the possibility that indigenous microorganisms may play important roles in nitrobenzene degradation. Consequently, this study aimed to verify this possibility and investigate the potential nitrobenzene degraders among indigenous microorganisms in sediments. The abundance of inoculated strain JS45 and indigenous bacteria in sediments was quantified using real-time polymerase chain reaction. Furthermore, community structure of the indigenous bacteria was analyzed through high throughput sequencing based on Illumina MiSeq platform. The results showed that indigenous bacteria in native sediments were abundant, approximately 1014 CFU/g dry weight, which is about six orders of magnitude higher than that in fertile soils. In addition, the levels of indigenous Proteobacteria (Acinetobacter, Comamonadaceae_ uncultured, Pseudomonas, and Thauera) and Firmicutes (Clostridium, Sporacetigenium, Fusibacter, Youngiibacter, and Trichococcus) increased significantly during nitrobenzene removal. Their quantities sharply decreased after nitrobenzene was removed completely, except for Pseudomonas and Thauera. Based on the results, it can be concluded that indigenous microorganisms including Proteobacteria and Firmicutes can have great potential for removing nitrobenzene from sediments. Although P. australis - JS45 system was set up in an attempt to eliminate nitrobenzene from sediments, and the system did not meet the expectation. The findings still provide valuable information on enhancing nitrobenzene removal by optimizing the sediment conditions for better growth of indigenous Proteobacteria and Firmicutes.
相似文献
599.
Lu Ao Wenjun Liu Yang Qiao Cuiping Li Xiaomao Wang 《Frontiers of Environmental Science & Engineering》2018,12(6):9
600.
Xu Zhang Huanhuan Yang Xinlei Wang Wen Song Zhaojie Cui 《Frontiers of Environmental Science & Engineering》2018,12(4):6
In this research, supercritical carbon dioxide extraction (SFE) showed better extraction effect when compared with Solid- liquid extraction (SLE), Soxhlet extraction (SE) and Ultrasonic extraction (UE), not only in the rate but also the time. The comparison among these three extraction modifiers, including acetone, ethanol and methanol demonstrated that ethanol was preferred to SFE due to its high extraction effect and low toxicology. In addition, parameter of SFE, influence of temperature and pressure were investigated, and the best extraction effect was achieved at the optima conditions, temperature of 40°C and the pressure of 35 MPa. Thus, SFE is a highly effective method for flavonols extraction, requiring minimum energy and producing non-toxic byproduct. SFE-GC system is applied for the evaluation on flavonols that plays a key role in plant resistance to heavy metal, with its content and synthetase gene expression significantly increasing in plant when threatened by heavy metal. Besides, results indicated that flavonols can improve plant resistance to oxidative stress by quenching the redundant ROS in matrix.
相似文献