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131.
As inequality in wealth and income continues to grow, it is important to consider the implications of financial disparities for worker motivation and behavior. While workers with socioeconomic disadvantages have a decreased chance of career success and upward social mobility, the potential mechanisms linking financial status to work motivation outcomes are not fully known. Drawing on theory on resource scarcity, we address this issue and propose that financial inadequacy shapes the extent to which workers consider and plan for the future, with consequences for goal-striving strategies throughout adulthood. Latent change analyses of data from a heterogeneous sample of 4,446 working adults largely supported the hypotheses. Results showed that a high level of financial inadequacy predicted increases in short-term time horizon and decreases in future-oriented planning, which then predicted disadvantageous changes in goal-striving strategies over an 18-year period. Short-term time horizon also predicted subsequent increases in financial inadequacy. By highlighting the motivational challenges associated with inadequate finances that accompany low-wage employment, our study offers evidence for the motivational mechanisms that may reinforce economic inequality and social mobility in the workforce. 相似文献
132.
Lorraine Whitmarsh John Turnpenny Bjőrn Nykvist 《Journal of Environmental Planning and Management》2009,52(8):973-991
Sustainability policy making is hampered by a tendency towards sector-based, short-term and often techno-fix perspectives. This paper describes a novel policy development and assessment framework – Integrated Sustainability Assessment (ISA) – that may help address problems of unsustainability in a more integrated and strategic manner. ISA involves two primary methods: transition analysis and stakeholder engagement. The ISA case study on sustainable passenger mobility suggests ISA is well equipped to produce a holistic analysis of mobility systems, illustrate radical alternatives to the status quo and foster social learning. Further research should explore its potential to induce long-term behavioural or institutional change. 相似文献
133.
134.
Paul Fenton 《Journal of Environmental Planning and Management》2017,60(9):1660-1682
This study explores the implications of improved access to national rail and road infrastructure for urban planning and land use in two small Swedish towns. The promotion of sustainable mobility is considered a strategic objective at the municipal level, yet the study questions the extent to which national investments, and increased access to regional labour markets, support local efforts to increase sustainable mobility. The results indicate that municipalities struggle to adopt coherent approaches to increasing sustainable mobility and continue to develop physical plans that induce use of motor vehicles, a trend reinforced by national investments in road infrastructure in peri-urban areas. 相似文献
135.
为明确异菌脲在土壤中的迁移和归趋特征,采用室内模拟方法研究异菌脲在4种不同类型土壤中的降解和移动性以及不同因素对异菌脲降解的影响。结果表明,异菌脲在不同类型土壤中的降解顺序为东北黑土青海草甸土南京黄棕壤江西红壤,降解半衰期分别为7.2、8.6、12.7和16.9 d,异菌脲在4种土壤中均属于易降解农药。土壤湿度越大,异菌脲降解越快,渍水条件下降解速率加快,说明厌氧微生物对异菌脲降解起重要作用。微生物和有机质对异菌脲在土壤降解过程中有一定的促进作用,在微生物、有机质存在的条件下异菌脲降解速率分别提高1.8倍、3.7倍。薄层层析试验表明,异菌脲在南京黄棕壤、东北黑土、江西红壤和青海草甸土的比移值(R_f)分别为0.19、0.17、0.29和0.17,异菌脲在4种土壤中均属于不易移动,土柱淋溶试验结果表明,异菌脲在4种土壤中均属于难淋溶,不易通过淋溶作用造成地下水污染。 相似文献
136.
Modelling the closure-related geochemical evolution of groundwater at a former uranium mine 总被引:2,自引:0,他引:2
J. G. Bain K. U. Mayer D. W. Blowes E. O. Frind J. W. H. Molson R. Kahnt U. Jenk 《Journal of contaminant hydrology》2001,52(1-4):109-135
A newly developed reactive transport model was used to evaluate the potential effects of mine closure on the geochemical evolution in the aquifer downgradient from a mine site. The simulations were conducted for the K?nigstein uranium mine located in Saxony, Germany. During decades of operation, uranium at the former mine site had been extracted by in situ acid leaching of the ore underground, while the mine was maintained in a dewatered condition. One option for decommissioning is to allow the groundwater level to rise to its natural level, flooding the mine workings. As a result, pore water containing high concentrations of dissolved metals, radionuclides, and sulfate may be released. Additional contamination may arise due to the dissolution of minerals contained in the aquifer downgradient of the mine. On the other hand, dissolved metals may be attenuated by reactions within the aquifer. The geochemical processes and interactions involved are highly non-linear and their impact on the quality of the groundwater and surface water downstream of the mine is not always intuitive. The multicomponent reactive transport model MIN3P, which can describe mineral dissolution-precipitation reactions, aqueous complexation, and oxidation-reduction reactions, is shown to be a powerful tool for investigating these processes. The predictive capabilities of the model are, however, limited by the availability of key geochemical parameters such as the presence and quantities of primary and secondary mineral phases. Under these conditions, the model can provide valuable insight by means of sensitivity analyses. 相似文献
137.
重金属化学活性评估方法准确性质疑--以煤矸石样品为例 总被引:5,自引:0,他引:5
重金属元素化学活性的大小是决定它们环境行为最主要的因素之一,我们曾分别用总量法,实验模拟法,环境地球化学法和化学形态分析法对煤矸石样品所含的重金属元素进行过环境影响分析,试图了解自然风化条件下这些有害元素潜在的生态环境效应,结果发现重金属元素的化学活性除了与它们在样品中含量的高低,赋存状态和化学形态等因素有关外,更主要地是取决于样品基质的组成和结构,由于大量有机质的络合和风化过程中生成的铁的胶体的吸附,从煤矸石释放出的重金属元素的化学活性受到明显限制,它们对环境的污染可能仅限于煤矸石堆周围有限的范围。 相似文献
138.
139.
Aging effect on the mobility and bioavailability of copper (Cu) was investigated using a spiked soil with different incubation periods from 3 to 56 d. Wheat was planted and earthworm was cultured separately in the incubated soils. The mobility of Cu in soil was evaluated by a chemical fractionation scheme and the toxicity and bioavailability were assessed by measuring the biomass and Cu concentration in tissues. Results showed that aging had a significant effect on Cu fraction distribution, of which Cu tended to incorporate from the exchangeable into more stable fractions such as the reducible and oxidisable fractions. However, aging had little effect on Cu bioavailability to wheat and earthworms. Comparing the soil being incubated for 3 d and 56 d, Cu concentration in wheat roots decreased from 14.5 to 12.8 mg/kg, and no significant changes in Cu concentration were observed in both wheat shoots and earthworms. The Cu concentration was around 2.0 and 50 mg/kg for wheat shoots and earthworms, respectively, irrespective of soil incubation time. The CaCl2-extractable Cu had a linear relationship with Cu concentration in wheat roots (R2 = 0.65, P < 0.05), but no linear relationship can be found for wheat shoots and earthworms. Biological control may be more crucial for Cu accumulation in organism than the changes in soil Cu fraction caused by aging. 相似文献
140.
García R Rubio V Vegas I Frías M 《Environmental science and pollution research international》2009,16(3):274-277
Background, aim and scope One of the problems to affect Portland cement matrices is low resistance to aggressive agents, due principally to the presence
of a high content of portlandite in the hydrated cements. Pozzolanic materials have played an important role in the improving
the durability of cement-based materials for decades. This work studies the behaviour of cement mortar matrices blended with
10% calcined paper sludge (source for metakaolinite) and exposed to different environmental conditions (saline and non-saline
environments) after 6 and 12 months of exposure.
Materials and methods Two cements were studied: an ordinary Portland cement (CEM 1, 42.5R), acting as reference cement, and a blended cement formulated
by mixing 90% (by mass) of CEM 1, 42.5R with 10% (by mass) of paper sludge calcined at 700°C for 2 h. The specimens were exposed
1 year to saline and non-saline environments. All the mineralogy samples were studied through X-ray diffraction and scanning
electron microscopy (SEM) equipped with an energy dispersive X-ray analyser. The in-depth study on ionic mobility was performed
on samples subjected to natural exposure (coast and tableland) for 6 and 12 months.
Results Portland cement was composed of quartz, calcite, calcium hydroxide and tobermorite gels. The pozzolanic cement (10% calcined
paper sludge) is of the same composition but a high calcite concentration and barium carbonate. SEM analysis from coastline
show deposits of variable composition. The deposits are identified on the surface of different mineral components. The minerals
from tableland are much fractured, i.e. calcite and feldspars. Inside the fractures, the deposits and the ions are located
and trapped superficially.
Discussion SEM analysis of control cement Portland and 10% calcined paper sludge shows deposits on quartz and calcite with a very high
concentration of Pb, Zn, Cl and barium sulphate. A very porous aspect is due to the presence of the different aggregate types.
This porous configuration permits retention of the ion environment. The pozzolanic cement in environments subject to the saline
mist favours the retention and transport of ions observed. Something similar also happens with the increase in exposure to
outdoor weather. Non-saline samples show temperature changes (ice or thaw cycles). Barium retention is kept on the surface
in fracture lines by the gelification processes. In general, it may be inferred that an increase in exposure time increases
the diffusion of ions towards test piece interiors. The chemical composition profiles show that the ions present different
penetration speeds.
Conclusions The results indicate the better vulnerability of pozzolanic cements from calcined paper sludge in saline and non-saline environments.
The cements with a 10% addition of calcined paper sludge favour retention and transport of ion has been observed.
Recommendations and perspectives Today, projects are centred on a new recycling line for industrial waste of this kind, with special attention on its incorporation
in cement manufacture as a pozzolanic material, setting the most appropriate activation conditions of the mineralogical compound
in this waste (kaolinite and metakaolinite) and taking them as a starting point for this project. The use of pozzolanic cement
with 10% addition of calcined paper sludge is a system which favours ionic retention. 相似文献