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991.
Bert Schreurs Eva Derous Edwin A. J. Van Hooft Karin Proost Karel De Witte 《组织行为杂志》2009,30(6):761-783
Applicants' pretest expectations about the forthcoming selection procedure may serve as a key factor in applicants' decision‐making. The current study examined the validity of the theory of planned behavior (TPB) as an explanatory mechanism of the relationship between pretest selection expectations (warmth/respect, chance to demonstrate potential, difficulty of faking, unbiased assessment, feedback) and job pursuit behavior. Data were collected at two points in time, using a sample of applicants for the military. Selection expectations, job pursuit attitude, subjective norm, and controllability were significantly related to job pursuit intention. Job pursuit attitude mediated the relationship between selection expectations and job pursuit intention. Subjective norm and time lag were the only significant predictors of job pursuit behavior. Practical implications, strengths and limitations, as well as directions for further research are discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
992.
Jean-Daniel Paris Mikhail Yu. Arshinov Philippe Ciais Boris D. Belan Philippe Nédélec 《Atmospheric environment (Oxford, England : 1994)》2009,43(6):1302-1309
Ultra-fine particle number concentrations were measured over Siberia during two large-scale airborne measurement campaigns in April and September 2006. During both campaigns, an aircraft flew between Novosibirsk and Yakutsk, collecting every 200 km vertical profiles up to 7 km. This dataset was completed by 5 years of monthly profiles above Novosibirsk. Particle number concentration was measured in the size ranges 3–70 and 70–200 nm, along with other tracers. Free troposphere (FT) particle concentrations (N3–200) varied between 60 and 460 cm?3, inferior to boundary layer concentrations (100–7000 cm?3). In April, high concentrations of ~500 cm?3 were observed in a polluted air mass recently uplifted at 5–6 km altitude over eastern Siberia, with no sign of significant new particle formation. In September, particle concentrations decreased with altitude, but with a steeper gradient in N70–200 compared to N3–70, the latter accounting for 90% of the total particle concentration in the free troposphere at 6–7 km altitude. Because ultra-fine particles presumably have short lifetimes, these observed particles could have been formed in situ in the clean Siberian atmosphere. Two cases of possible nucleation with high concentration and N3–70/N70–200 ratios are reported for the September campaign, in the upper troposphere and in cloud outflow in the mid-troposphere. In the seasonal analysis, a FT N3–70 maximum is found in July–August between 6 and 7 km altitude, with N3–70 accounting for ~90% of N3–200 supporting the hypothesis of in situ formation in the FT. A secondary FT maximum of N3–70 was identified later in autumn. In the boundary layer, seasonally maximum N3–70 concentrations were found over Novosibirsk in May and September, but not in summer, possibly due to scavenging by precipitations and a large condensational sink from biomass burning aerosols. Our dataset has a limited size resolution and no speciation capability; more investigation is thus required to understand the conditions leading to in situ nucleation processes in the Siberian air shed. 相似文献
993.
Influence of temperature and soil type on the toxicity of three pesticides to Eisenia andrei 总被引:1,自引:0,他引:1
P. Mangala C.S. De Silva Asoka Pathiratne Cornelis A.M. van Gestel 《Chemosphere》2009,76(10):1410-1415
Expansion of agriculture in the tropics has increased the use of pesticides that may affect the soil ecosystems. Few studies so far determined the effects of pesticides in the tropics and tropical risk assessment therefore often relies on data from temperate conditions. Hence we compared the toxicity of chlorpyrifos, carbofuran and carbendazim to the earthworm Eisenia andrei at two different temperatures reflecting temperate and tropical conditions. The toxicity of the three pesticides in both conditions decreased in the order carbendazim > carbofuran > chlorpyrifos. For chlorpyrifos and carbofuran, but not for carbendazim, survival was more sensitive at the higher temperature, probably due to increased earthworm activity. Sub-lethal effects (reproduction and growth) however, varied inconsistently with temperature and soil types. We conclude that toxicity of pesticides in tropics may not be predicted from data generated under temperate conditions, even within the same species. 相似文献
994.
995.
Jorge Pey Xavier Querol Andrés Alastuey Sergio Rodríguez Jean Philippe Putaud Rita Van Dingenen 《Atmospheric environment (Oxford, England : 1994)》2009,43(29):4407-4415
Extensive measurements on particle number concentration and size distribution (13–800 nm), together with detailed chemical composition of PM2.5 have constituted the main inputs of the database used for a source apportionment analysis. Data were collected at an urban background site in Barcelona, Western Mediterranean.The source identification analysis helped us to distinguish five emission sources (vehicle exhausts, mineral dust, sea spray, industrial source and fuel-oil combustion) and two atmospheric processes (photochemical induced nucleation and regional/urban background particles derived from coagulation and condensation processes). After that, a multilinear regression analysis was applied in order to quantify the contribution of each factor.This study reveals that vehicle exhausts contribute dominantly to the number concentration in all the particle sizes (52–86%), but especially in the range 30–200 nm. This work also points out the importance of the regional and/or urban formed aerosols (secondary inorganic particles) on the total number concentration (around 25% of the total number), with a higher impact on the accumulation mode. The photo-chemically induced nucleation of aerosols only represents a small proportion of the total number as an annual mean (3%), but is very relevant when considering only the nucleation mode (13–20 nm) fraction (23%). The other sources recognized registered sporadic contributions to the total number, coinciding with specific meteorological scenarios.This study discloses the main sources and features affecting and controlling the fine and ultra-fine aerosols in a typical city in the Western Mediterranean coast. Whereas the road traffic appears to be the most important source of sub-micrometric aerosols, other sources may not be negligible under specific meteorological conditions. 相似文献
996.
Vulnerability and risk evaluation of agricultural nitrogen pollution for Hungary's main aquifer using DRASTIC and GLEAMS models 总被引:5,自引:1,他引:4
Leone A Ripa MN Uricchio V Deák J Vargay Z 《Journal of environmental management》2009,90(10):2969-2978
In recent years, the significant improvement in point source depuration technologies has highlighted problems regarding, in particular, phosphorus and nitrogen pollution of surface and groundwater caused by agricultural non-point (diffuse) sources (NPS). Therefore, there is an urgent need to determine the relationship between agriculture and chemical and ecological water quality.This is a worldwide problem, but it is particularly relevant in countries, such as Hungary, that have recently become members of the European Community. The Italian Foreign Ministry has financed the PECO (Eastern Europe Countries Project) projects, amongst which is the project that led to the present paper, aimed at agricultural sustainability in Hungary, from the point of view of NPS. Specifically, the aim of the present work has been to study nitrates in Hungary's main aquifer. This study compares a model showing aquifer intrinsic vulnerability to pollution (using the DRASTIC parameter method; Aller et al. [Aller, L., Truman, B., Leher, J.H., Petty, R.J., 1986. DRASTIC: A Standardized System for Evaluating Ground Water Pollution Potential Using Hydrogeologic Settings. US NTIS, Springfield, VA.]) with a field-scale model (GLEAMS; Knisel [Knisel, W.G. (Ed.), 1993. GLEAMS—Groudwater Leaching Effects of Agricultural Management Systems, Version 3.10. University of Georgia, Coastal Plain Experimental Station, Tifton, GA.]) developed to evaluate the effects of agricultural management systems within and through the plant root zone. Specifically, GLEAMS calculates nitrate nitrogen lost by runoff, sediment and leachate.Groundwater monitoring probes were constructed for the project to measure: (i) nitrate content in monitored wells; (ii) tritium (3H) hydrogen radioisotope, as a tool to estimate the recharge conditions of the shallow groundwater; (iii) nitrogen isotope ratio δ15N, since nitrogen of organic and inorganic origin can easily be distinguished.The results obtained are satisfactory, above all regarding the DRASTIC evaluation method, which is shown to satisfactorily explain both low and high aquifer vulnerability, and furthermore proves to be a good tool for zoning hydrogeological regions in terms of natural system susceptibility to pollution. The GLEAMS model, however, proves not to be immediately usable for predictions, above all due to the difficulty in finding sufficient data for the input parameters. It remains a good tool, but only after an accurate validation, for decision support systems, in the specific case to integrate intrinsic vulnerability, from DRASTIC (or similar methods), with land use nitrate loads from GLEAMS, or similar methods.The PECO project has proved a positive experience to highlight the fundamental points of a decision support system, aimed to mitigate the nitrate risk for groundwater coming from Hungarian agricultural areas. 相似文献
997.
Bruno De Cordier 《Disasters》2009,33(4):608-628
This paper focuses on the emergence and modus operandi of Muslim faith-based aid organisations from the West, particularly those from the United Kingdom. Through case studies of Islamic Relief Worldwide and Muslim Hands, it examines the actual and potential added value generated by these humanitarian players in Muslim-majority contexts at times when aid actors from or associated with the West are being perceived by some as instrumental to the political agendas of Western powers, or are being confronted with the consequences thereof. The study analyses Muslim faith-based aid organisations' transnational networks, their implementing partnerships with local faith-based non-governmental organisations (NGOs), and their security position within and their access to insecure contexts, drawing on field examples and opinion from Central Asia, Iraq and Pakistan. It thereby argues that there is ground for an expansion of the role of Muslim aid actors, because of the existence of social and political realities in the field that cannot be always effectively tackled by the dominant international development approaches. 相似文献
998.
Cinzia De Vittor Federica Relitti Martina Kralj Stefano Covelli Andrea Emili 《Environmental science and pollution research international》2016,23(13):12566-12581
In the shallow environment, the nutrient and carbon exchanges at the sediment–water interface contribute significantly to determine the trophic status of the whole water column. The intensity of the allochthonous input in a coastal environment subjected to strong anthropogenic pressures determines an increase in the benthic oxygen demand leading to depressed oxygen levels in the bottom waters. Anoxic conditions resulting from organic enrichment can enhance the exchange of nutrients between sediments and the overlying water. In the present study, carbon and nutrient fluxes at the sediment–water interface were measured at two experimental sites, one highly and one moderately contaminated, as reference point. In situ benthic flux measurements of dissolved species (O2, DIC, DOC, N-NO3 ?, N-NO2 ?, N-NH4 +, P-PO4 3?, Si-Si(OH)4, H2S) were conducted using benthic chambers. Furthermore, undisturbed sediment cores were collected for analyses of total and organic C, total N, and biopolymeric carbon (carbohydrates, proteins, and lipids) as well as of dissolved species in porewaters and supernatant in order to calculate the diffusive fluxes. The sediments were characterized by suboxic to anoxic conditions with redox values more negative in the highly contaminated site, which was also characterized by higher biopolymeric carbon content (most of all lipids), lower C/N ratios and generally higher diffusive fluxes, which could result in a higher release of contaminants. A great difference was observed between diffusive and in situ benthic fluxes suggesting the enhancing of fluxes by bioturbation and the occurrence of biogeochemically important processes at the sediment–water interface. The multi-contamination of both inorganic and organic pollutants, in the sediments of the Mar Piccolo of Taranto (declared SIN in 1998), potentially transferable to the water column and to the aquatic trophic chain, is of serious concern for its ecological relevance, also considering the widespread fishing and mussel farming activities in the area. 相似文献
999.
1000.
利用具有代表性的三峡地区区域性降水个例,基于WRF模式,在模式下垫面中加入长江水体以及修改局地地形,研究局地环流和气象要素对局地下垫面变化的响应。结果表明:加入长江水体后,不同区域性降水个例空间降水变化上,没有出现明显的降水变化区,表明长江水体对区域局地性降水影响较小;同时加入长江水体和修改地形高度后,空间上降水具有明显的变化,且与修改地形后的降水空间变化较一致,表明局地地形对区域降水空间变化具有重要影响;加入长江水体后,近地面2 m高度相对湿度变化上,不同区域性降水个例表现不一,总体上对局地相对湿度影响较小;近地面2 m温度、地表向上的水汽通量和地表向上的潜热通量均为增加,在局地地形的“喇叭口”效应作用下,长江水体拐弯处增加效应明显 相似文献