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111.
In the present study, selected advanced oxidation processes (AOPs)—namely, photo-Fenton (with Fe2+, Fe3+, and potassium ferrioxalate—FeOx—as iron sources), solar photo-Fenton, Fenton, and UV/H2O2—were investigated for degradation of the antineoplastic drug mitoxantrone (MTX), frequently used to treat metastatic breast cancer, skin cancer, and acute leukemia. The results showed that photo-Fenton processes employing Fe(III) and FeOx and the UV/H2O2 process were most efficient for mineralizing MTX, with 77, 82, and 90 % of total organic carbon removal, respectively. MTX probably forms a complex with Fe(III), as demonstrated by voltammetric and spectrophotometric measurements. Spectrophotometric titrations suggested that the complex has a 2:1 Fe3+:MTX stoichiometric ratio and a complexation constant (K) of 1.47 × 104 M–1, indicating high MTX affinity for Fe3+. Complexation partially inhibits the involvement of iron ions and hence the degradation of MTX during photo-Fenton. The UV/H2O2 process is usually slower than the photo-Fenton process, but, in this study, the UV/H2O2 process proved to be more efficient due to complexing of MTX with Fe(III). The drug exhibited no cytotoxicity against NIH/3T3 mouse embryonic fibroblast cells when oxidized by UV/H2O2 or by UV/H2O2/FeOx at the concentrations tested.  相似文献   
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Attitudes have been a commonly used psychological measure of program effectiveness in conservation social science research. The major limitation of this approach is that attitudes do not always translate into behavior and therefore may not provide an accurate assessment of program success. Given that achieving conservation goals generally relies on understanding and changing human behavior, we argue for the need to assess behavior rather than attitudes as an indicator of conservation outcomes. Psychological theory shows that attitudes and behavior are distinct, but related, concepts. Measuring conservation behaviors involves identifying the target behavior or behaviors and the optimal time to measure and then selecting the most appropriate method of measurement (i.e., direct observation, objective indicators, self-reported behavior, and behavioral intentions) that considers the strengths and weaknesses of each approach. We call for conservation programs to focus on influencing behavior rather than attitudes alone and encourage conservation practitioners and researchers to collect high-quality behavioral data to more effectively inform policy and programs.  相似文献   
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Article impact statement: Structured decision making can be used to identify an optimal source population for conservation introductions.  相似文献   
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Remote sensing can advance the work of the Circumpolar Biodiversity Monitoring Program through monitoring of satellite-derived terrestrial and marine physical and ecological variables. Standardized data facilitate an unbiased comparison across variables and environments. Using MODIS standard products of land surface temperature, percent snow covered area, NDVI, EVI, phenology, burned area, marine chlorophyll, CDOM, sea surface temperature, and marine primary productivity, significant trends were observed in almost all variables between 2000 and 2017. Analysis of seasonal data revealed significant breakpoints in temporal trends. Within the terrestrial environment, data showed significant increasing trends in land surface temperature and NDVI. In the marine environment, significant increasing trends were detected in primary productivity. Significantly earlier onset of green up date was observed in bioclimate subzones C&E and longer end of growing season in B&E. Terrestrial and marine parameters showed similar rates of change with unidirectional change in terrestrial and significant directional and magnitude shifts in marine.  相似文献   
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Workplace resilience is a necessity for organizations and employees given it assists them in overcoming adversity and ultimately succeeding. However, organizational scholars have largely overlooked this construct. In this Incubator, we briefly summarize extant research on workplace resilience to highlight opportunities for theory building and advancement of empirical research. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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在圣保罗的各加油站,用户可以自行选择加汽油或加乙醇。从20世纪70年代中期开始,巴西就着手用乙醇替代进口的汽油,其做法是将乙醇与汽油混合作为氧化剂或燃料补充剂用于汽油车辆,也可单独使用在以任何乙醇和汽油混合料作燃料的车辆上。巴西的乙醇是从当地产的甘蔗中蒸馏出来的。目前,乙醇已占巴西销售油品的40%。乙醇可以从以植物为基础的各类饲料作物中提取,最普通的是谷类和糖类作物。  相似文献   
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引言 近50年来美国住宅开发大量增加.所增住宅很多集中在市区,美国几乎80%的人口现今居住在城里[1].当人们从农村地区和市中心向城市边缘和郊区迁移时,城市变得越来越大,人口增加、地区扩大[1].在城市扩建时,开发商把农业用地和林区的土地转变成城市和城郊[2,3].于是,在城市的边缘、在城乡结合部常常夹杂着被建筑工地、新开发的住宅和商业网点所分割的小块农田和林地以及现在被城市扩建所吞噬的过去十分偏僻的住宅[1,2].  相似文献   
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