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511.
The present study integrates personality approach and social cognition approach to investigate the relationships between risk tolerance, risk perception, hazardous attitude and safety operation behavior in order to understand the mechanisms underlying pilots’ safety operation behavior in aviation. The study sample consisted of 118 commercial airline pilots from China Southern Airlines Ltd. The results show risk tolerance displays an indirect effect on safety operation behavior through influencing hazardous attitude; risk perception has a significant moderating effect on the relationship between risk tolerance and safety operation behavior. Based on the above, it can be concluded that the low risk tolerance primarily influences safety operation behavior indirectly through affecting hazardous attitude. With risk perception increasing, the negative effects of risk tolerance on safety operation behavior are gradually reduced. Practical implications for aviation safety campaigns are also discussed.  相似文献   
512.
2013年1月中旬对大纵湖5个采样点的大型底栖动物进行调查,共采集底栖动物29种,其中DZ1的优势种为苏氏尾鳃蚓(Branchiura sowerbyi);其他各点的优势种为长角涵螺(Alocinma longicornis)。采用理化分析、Shannon-Wiener指数、Margalef指数、BPI指数对各点水质进行了综合评价。结果表明:DZ4属于β-中污染水质,其他各点属于α-中污染水质;对主要的环境因子与底栖动物密度进行相关性分析,发现DO与底栖动物群落未显著相关,NH3-N、NO-3-N、CODMn等因子更能代表水体的污染水平和营养状态,且随着营养状态的升高,耐污种类的颤蚓类数量呈现出增高趋势;寡毛类、蛭类、摇蚊幼虫、水生昆虫和软体动物5者之间除了寡毛类和蛭类存在极显著正相关性之外,其他无显著相关性。  相似文献   
513.
雾霾的形成,主要是城市静风、大气逆温层以及大气中细颗粒物污染的综合效应。控制和预防雾霾,应该加强机动车的监控、鼓励清洁能源汽车的研发、生产和销售。大力发展城市公共交通、建设城市公共自行车网络,严格建筑扬尘的管理和对重点大气污染源的治理,实行联防联控和区域联动机制,环保部门要全面开展雾霾监测,会同气象部门,结合气象参数等各方面资料,建立健全雾霾的预警预报体系,同时倡导全民低碳出行的生产、生活理念以及加强环保的宣传教育,提高全民环保意识。  相似文献   
514.
Perfluorooctane sulfonate(PFOS) and ZnO nanoparticles(nano-ZnO) are widely distributed in the environment.However,the potential toxicity of co-exposure to PFOS and nano-ZnO remains to be fully elucidated.The test investigated the effects of co-exposure to PFOS and nano-ZnO on the hypothalamic–pituitary–thyroid(HPT) axis in zebrafish.Zebrafish embryos were exposed to a combination of PFOS(0.2,0.4,0.8 mg/L) and nano-ZnO(50 mg/L)from their early stages of life(0–14 days).The whole-body content of TH and the expression of genes and proteins related to the HPT axis were analyzed.The co-exposure decreased the body length and increased the malformation rates compared with exposure to PFOS alone.Co-exposure also increased the triiodothyronine(T3) levels,whereas the thyroxine(T4)content remained unchanged.Compared with the exposure to PFOS alone,exposure to both PFOS(0.8 mg/L) and nano-ZnO(50 mg/L) significantly up-regulated the expression of corticotropin-releasing factor,sodium/iodidesymporter,iodothyronine deiodinases and thyroid receptors and significantly down-regulated the expression of thyroid-stimulating hormone,thyroglobulin(TG),transthyretin(TTR) and thyroid receptors.The protein expression levels of TG and TTR were also significantly down-regulated in the co-exposure groups.In addition,the expression of the thyroid peroxidase gene was unchanged in all groups.The results demonstrated that PFOS and nano-ZnO co-exposure could cause more serious thyroid-disrupting effects in zebrafish than exposure to PFOS alone.Our results also provide insight into the mechanism of disruption of the thyroid status by PFOS and nano-ZnO.  相似文献   
515.
新型除氟剂竹炭的优选和改性方法实验研究   总被引:1,自引:0,他引:1  
采用不同产地的竹炭进行除氟研究,分别进行了直接除氟和改性后除氟的效果比较。在水浴恒温振荡箱,振荡速度100 r/min,温度30件下,保持固液比0.03,反应1.5 h,处理初始氟浓度10 mg/L的溶液,浙江丽水的机械竹炭的直接除氟效果比其它地方的竹炭都好,其对氟去除率为47.8%。通过该竹炭的直接除氟工艺参数优化结果可知,pH是影响竹炭除氟的关键因素,最佳值为4;随着竹炭量的增大,氟离子的去除率明显上升;氟离子的初始浓度增大,竹炭的单位吸附量也逐渐上升;反应时间为90 min时,反应逐渐趋于平衡。选用Al2(SO4)3对竹炭进行改性后,浙江丽水的机械竹炭的除氟率有很大的上升;采用MgSO4改性后各类竹炭除氟效果均有所下降。采用Fe2(SO4)3改性后,氟离子的去除率达到91.8%,剩余浓度为0.82 mg/L,达到国家饮用水的标准。  相似文献   
516.
噪声自动监测在中国才刚刚起步,其各项规范还没有随之确立,这就需要进行一系列的噪声自动监测实验,以获得各项规范确立的指标。通过在四个类别的标准适用区进行的噪声监测试验,利用获得的试验数据进行统计分析,找出噪声Leq小时值的统计特征,对四个类别的标准适用区各日标准方差进行计算,获得标准方差最大与最小对应的日期,分别对其进行小时噪声等效声级进行抽样,以确定功能区噪声自动监测有效时间。经计算对任一类别的适用区日均值的获得至少需要连续监测,也就是功能区噪声自动监测有效时间是18个小时以上。  相似文献   
517.
Water consumption in agricultural activities is the main water use in inland oases in Northwest China. Research on water conservation in agriculture is of great significance to alleviate the conflict between the use of agricultural and ecological water and is of great importance to local farmers’ livelihoods. This study, based on traditional irrigation practices (flood irrigation and fixed irrigation frequency) of Minqin County in Shiyang River Basion, was designed to reveal the impacts of five irrigation quotas (1 800, 1 440, 1 080, 720, and 360 m3/hm2) on crop yield, biomass, irrigation water use efficiency (IWUE), and economic water productivity (EWP) to determine the optimal irrigation for five crops and guide local irrigation practices. The results showed that: (1) Under the five irrigation quotas, IWUE of corn, with the highest of 12.27 kg/m3, was higher than the other four crops; (2) The average EWP of cotton with a 2-year-average of 8.0 yuan/m3 was higher than the other four crops. Thus, the economic output of cotton is the best under the same irrigation quota; (3) Considering the yield, IWUE, EWP, and biomass, corn was better than the other four typical crops; and (4) 1 080 m3/hm2 was the optimal irrigation quota for sunflower in local planting practices. In addition, 720 m3/hm2 was suitable for corn, pepper, wheat, and cotton as their irrigation quota. This study shows that reducing the amount of irrigation quota in the Shiyang River Basin can effectively improve local IWUE and EWP. © 2022 Authors. All rights reserved.  相似文献   
518.
• A fine fibre (40–60 nm diameter) interlayer (~1 µm thickness) was electrospun. • Fine fibre interlayer promoted formation of defect-free dense polyamide layer. • FO membrane with dual-layer substrate had less organic fouling potential. • High reverse salt flux accelerated organic fouling on FO membrane. Nanofibre-supported forward osmosis (FO) membranes have gained popularity owing to their low structural parameters and high water flux. However, the nanofibrous membranes are less stable in long-term use, and their fouling behaviours with foulants in both feed solution (FS) and draw solution (DS) is less studied. This study developed a nanofibrous thin-film composite (TFC) FO membrane by designing a tiered dual-layer nanofibrous substrate to enhance membrane stability during long-term usage and cleaning. Various characterisation methods were used to study the effect of the electrospun nanofibre interlayer and drying time, which is the interval after removing the M-phenylenediamine (MPD) solution and before reacting with trimesoyl chloride (TMC) solution, on the intrinsic separation FO performance. The separation performance of the dual-layer nanofibrous FO membranes was examined using model foulants (sodium alginate and bovine serum albumin) in both the FS and DS. The dual-layer nanofibrous substrate was superior to the single-layer nanofibrous substrate and showed a flux of 30.2 L/m2/h (LMH) when using 1.5 mol/L NaCl against deionised (DI) water in the active layer facing draw solution (AL-DS) mode. In the fouling test, the water flux was effectively improved without sacrificing the water/solute selectivity under the condition that foulants existed in both the FS and DS. In addition, the dual-layer nanofibrous TFC FO membrane was more robust during the fouling test and cleaning.  相似文献   
519.
Environmental Science and Pollution Research - Innovation in renewable energy generation, transmission, or distribution-related technologies (IREGT) is an effective way to deal with environmental...  相似文献   
520.
Environmental Science and Pollution Research - Collaborative innovation can promote scientific productivity and the development of clean technology and thus has a great potential in constraining...  相似文献   
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