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81.
Over the past decades, information and communication technologies (ICT) established themselves as the key force towards more effective and efficient usage of resources in our society, namely via better use of available information, automation, stakeholder involvement, and decision support. By analyzing recent advancements in knowledge offered by ICT, it is possible to identify their strong correlation with the principles, aims, and interests of sustainability science, which can be highly inspired by ICT-intensive domains. In this paper, we study the theoretical background on system thinking as an interpretative lens able to support better understanding of dimensions and dynamics involved in the domain of sustainability, and examine the role of ICT in advancing sustainability goals. Then, we analyze the domain of the Smart Grid as a prominent example of complex technological contribution in face of the challenges of sustainability, and present the insights from this domain, which are turned into sustainability guidelines for other domains, linking smartness, and sustainability in the light of systems thinking and Smart Grid experience. In summary, the core recommendation of this work is the employment of information technology to widen the scope of the sustainability “game” by sliding activities in time and space, and in engaging more “players” in the game, which is now made possible thanks to the advancement in ICT.  相似文献   
82.
The process of reducing acid leaching of manganiferous ore is aimed at the extraction of manganese from low grade manganese ores. This work is focused on the iron removal operation. The following items have been considered in order to investigate the effect of the main operating conditions on solid waste disposal and on the process costs: (i) type and quantity of the base agent used for iron precipitation, (ii) effective need of leaching waste separation prior to the iron removal operation, (iii) presence of a second leaching stage with the roasted ore, which might also act as a preliminary iron removal step, and (iv) effect of tailings washing on the solid waste classification. Different base compounds have been tested, including CaO, CaCO3, NaOH, and Na2CO3. The latter gave the best results concerning both the precipitation process kinetics and the reagent consumption. The filtration of the liquor leach prior to iron removal was not necessary, implying significant savings in capital costs. A reduction of chemical consumption and an increase of manganese concentration in the solution were obtained by introducing secondary leaching tests with the previously roasted ore; this additional step was introduced without a significant decrease of global manganese extraction yield. Finally, toxicity characteristic leaching procedure (TCLP) tests carried out on the leaching solid waste showed: (i) a reduction of arsenic mobility in the presence of iron precipitates, and (ii) the need for a washing step in order to produce a waste that is classifiable as not dangerous, taking into consideration the existing Environmental National Laws.  相似文献   
83.
Genetic and environmental factors influence insulin sensitivity (IS) during one's lifetime. Actually, uterine environment may affect IS at birth and later in life. In particular, various exogenous toxic substances, coupled to a genetic predisposition, may remarkably influence the regulation of the hypothalamus–hypophysis–adrenal gland axis, and the production or the activity of insulin, cerebral incretins, pro-inflammatory cytokines, and placental hormones. Owing to this reaction against environmental injuries, fetal growth and endocrine system development may be impaired, leading to low or large birth weight, or prematurity. Reduced growth in early life has been related to insulin resistance, which can be silent for years and evident in predisposed adults. The incidence of type 2 diabetes mellitus and obesity associated with sedentary lifestyle patterns and inadequate dieting behaviors in children and adolescents has rapidly increased during the last decade.Recent evidences suggest that the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-? (PPAR-?) gene and the angiotensin converting enzyme (ACE) I/D gene polymorphism combined with environmental factors, such as phthalates interfering with the post receptorial action of insulin, alter insulin-sensible tissues. Therefore, IS, deriving from a complex interaction between genotype and environment, may change during life and depends on previous metabolic control, which is a sort of metabolic memory. The goal for the future is preventing the complications associated with impaired IS through the control of exogenous factors and the use of drugs selectively effective on its pathogenesis.  相似文献   
84.
Six hundred and sixty-seven water samples were collected from public drinking water supplies in Sicily and analysed for electric conductivity and for their Cl(-), Br(-) and F(-) contents. The samples were, as far as possible, collected evenly over the entire territory with an average sampling density of about one sample for every 7,600 inhabitants. The contents of Cl(-) and Br(-), ranging between 5.53 and 1,302 mg/l and between <0.025 and 4.76 mg/l respectively, correlated well with the electric conductivity, a parameter used as a proxy for water salinity. The highest values were found both along the NW and SE coasts, which we attributed to seawater contamination, and in the central part of Sicily, which we attributed to evaporitic rock dissolution. The fluoride concentrations ranged from 0.023 to 3.28 mg/l, while the highest values (only three exceeding the maximum admissible concentration of 1.5 mg/l) generally correlated either with the presence in the area of crystalline (volcanic or metamorphic) or evaporitic rocks or with contamination from hydrothermal activity. Apart from these limited cases of exceeding F(-) levels, the waters of public drinking water supplies in Sicily can be considered safe for human consumption for the analysed parameters. Some limited concern could arise from the intake of bromide-rich waters (about 3% exceeding 1 mg/l) because of the potential formation of dangerous disinfection by-products.  相似文献   
85.
Waste management is of the utmost importance for many countries and especially for highly developed ones due to its implications on society. In particular, proper treatment before disposal of the solid urban waste organic fraction is one of the main issues that is addressed in waste management. In fact, the organic fraction is particularly reactive and if disposed in sanitary landfills without previous adequate treatment, a large amount of dangerous and polluting gaseous, liquid and solid substances can be produced. Some waste treatment processes can also present an opportunity to produce other by-products like energy, recycled materials and other products with both economic and environmental benefits. In this paper, the aerobic treatment of the organic fraction of solid urban waste, performed in a biocell plant with the possibility of recovering heat for civil or industrial needs, was examined from the thermodynamic point of view. A theoretical model was proposed both for the biological process of the organic fraction, as well as for the heat recovery system. The most significant results are represented and discussed.  相似文献   
86.
A pilot study was carried out in Tuscany, Italy, to provide preliminary information on the concentrations of polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorobiphenyls (DL-PCBs), and selected non-dioxin-like PCBs (NDL-PCBs) in groups of subjects living in the vicinity of two incineration plants. Seventy-four volunteers were enrolled from areas identified as under a potential impact from incinerator emissions and from not exposed areas. No significant differences were observed between subjects living in the two types of areas. Total concentrations of PCDDs, PCDFs, and DL-PCBs resulted to be in the range 23-30 pg WHO-TEQ g(-1), lipid base, for subjects in the 27-54 year age groups, while concentrations increased to 40-44 pgTEQ g(-1) for the two 55-67 year age groups. The levels of PCDDs and PCDFs were in good agreement with those observed for unexposed population groups in Italy, while the contribution to total TEQ from DL-PCBs was appreciably higher than those currently observed in the general population in Italy and other countries. As to NDL-PCBs, serum levels of the six "indicator" congeners were in the range 240-300 ng g(-1), lipid base, for subjects in the 27-54 year age groups. A raise in NDL-PCB body burden (430-470 ng g(-1), lipid base) was observed for the two 55+ year age groups, in agreement with the expected age-dependent increase. The findings from this study do not show an incremental exposure to PCDDs and PCDFs in the samples from subjects living around the two incineration plants, whereas PCB congener profiles in all samples suggest a possible impact on the area of interest of industrial activities from near industrial settlements.  相似文献   
87.
Mussels are widely used as bioindicator organisms for monitoring chemical pollutants including trace metals. These elements are natural constituents in the marine environment and their basal concentrations in the organisms can be influenced by several environmental and biological factors. The aim of this work was to extend our knowledge on the natural variability of trace metals in mussels tissues, focusing on seasonal and inter-annual fluctuations in a coastal reference site of the Adriatic coast (Portonovo); a total of 39 samplings were performed during 5 years, providing an extended data-set for tissue levels of As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V and Zn. Concentrations of trace metals in mussels tissues revealed marked seasonal fluctuations with significant differences between various sampling years. Such fluctuations appeared mostly related to phytoplanctonic blooms and especially to reproductive cycle which exhibited a certain inter-annual shift of the gametogenesis period. Lower concentrations were measured in summer months for the majority of elements while a different seasonal cycle was observed for arsenic, not correlated with gonadic development, neither with other elements. Chemical speciation of arsenic was characterized to distinguish compounds of natural origin from those potentially reflecting an anthropogenic impact. Arsenobetaine and arsenocholine were always the predominant forms (up to 85% of total arsenic), while a significant increase of dimethylarsine and trimethylarsine oxide in spring (24% of total arsenic) might reflect the effect of phytoplanctonic bloom on both geochemistry and trophic transfer of this element. A significant inter-annual variability was observed for both the seasonal cycle and the range of values measured for all the elements, with particularly marked differences for arsenic, ranging from less than 10 to more than 40 microg/g in summer periods of different years. Data obtained on reference mussels were used to assess the impact of 41 off-shore platforms distributed along 5 nautical districts in the Northern and Central Adriatic Sea. Organisms sampled on these structures from 2001 to 2005 exhibited a certain enrichment of cadmium and zinc, probably associated to the use of anodic electrodes. Marked annual and geographical variations were measured for concentrations of arsenic in mussels of different platforms. However, the comparison with results of Portonovo, allowed to exclude the anthropogenic impact of exploitation activities and revealed a natural regional gradient of arsenic levels in mussels tissues associated to the changing influence of the Po river runoff on seawater salinity. In particular the higher concentrations measured in organisms sampled from platforms in the Central compared to Northern Adriatic confirmed a significant relationship between salinity and arsenic bioaccumulation, consistent with a role of arsenobetaine as an acquired osmolyte for mussels. The overall results confirmed the importance of natural variability when assessing the potential impact of anthropogenic activities.  相似文献   
88.
The simultaneous action of power ultrasound and oxalic acid, as a chelating agent, rapidly converts chrysotile asbestos into water soluble material and a non-asbestos debris, not classifiable as hazardous under worldwide safety regulations.  相似文献   
89.
The purpose of this study was to evaluate “in field” the accumulation of virus in shellfish and compare it with the concentration of bacterial indicators. Individuals of Mytilus galloprovincialis were placed in two sampling station located in a contaminated coastal bay and in one control station located one kilometer offshore. The presence of Rotavirus and E. coli was assessed weekly both in seawater and in shellfish samples. The Rotavirus genome was detected in water, preliminarily concentrated by tangential flow ultrafiltration method, and in hepatopancreas of mussels by Real-Time PCR. E. coli was enumerated in water matrices by a filtering method and in mussels by the MPN method. Rotaviruses were not recorded in seawater, while in mussels they were detected since third week after placement. E. coli in mussels were always below the limits set in the Regulation (EC) 854/2004. This study suggests the need for a viral indicator to insure the safety for consumption of shellfish.  相似文献   
90.
Increasing awareness of environmental and energy problems has promoted greater governmental interest in selected waste collection and consequently has attracted the interest of several research groups to the challenge of converting recovered plastics into useful materials. The reactive blending of postconsumer polyethylene terephthalate (PET) with different polyolefins (PO) was studied in attempts to obtain a new material with enhanced properties with respect to the starting materials. The success of the project depends mainly on the possibility of obtaining a compatibilized blend between two starting polymers that, from chemical and thermomechanical viewpoints, are very different. This was approached by employing polyolefins bearing functional groups capable of specific interaction or chemical reaction with PET end groups. Ternary blends of very low density polyethylene (VLDPE)/PET/functionalized polyolefin (FPO) in a weight composition of 70/20/10 and binary blends of FPO/PET in a weight composition of 90/10 were prepared and studied to obtain reinforced polyolefin thermoplastic materials. Reactive blending was achieved in a Brabender Plastograph with a mixing chamber of 30 or 50cm3, at 250°C, and 40rpm for 10min. Differential scanning calorimetry, scanning electron microscopy, and tensile tests were used to investigate the phase behavior, the efficiency of compatibilization, and the mechanical properties of the blends.  相似文献   
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