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71.
Seafood mislabeling is common in both domestic and international markets. Studies on seafood fraud often report high rates of mislabeling (e.g., >70%), but these studies have been limited to a single sampling year, which means it is difficult to assess the impact of stricter governmental truth‐in‐labeling regulations. We used DNA barcoding to assess seafood labeling in 26 sushi restaurants in Los Angeles over 4 years. Seafood from 3 high‐end grocery stores were also sampled (n = 16) in 2014. We ordered 9 common sushi fish from menus, preserved tissue samples in 95% ethanol, extracted the genomic DNA, amplified and sequenced a portion of the mtDNA COI gene, and identified the resulting sequence to known fish sequences from the National Center for Biotechnology Information nucleotide database. We compared DNA results with the U.S. Food and Drug Administration (FDA) list of acceptable market names and retail names. We considered sushi‐sample labels that were inconsistent with FDA names mislabeled. Sushi restaurants had a consistently high percentage of mislabeling (47%; 151 of 323) from 2012 to 2015, yet mislabeling was not homogenous across species. Halibut, red snapper, yellowfin tuna, and yellowtail had consistently high (<77%) occurrences of mislabeling on menus, whereas mislabeling of salmon and mackerel were typically low (>15%). All sampled sushi restaurants had at least one case of mislabeling. Mislabeling of sushi‐grade fish from high‐end grocery stores was also identified in red snapper, yellowfin tuna, and yellowtail, but at a slightly lower frequency (42%) than sushi restaurants. Despite increased regulatory measures and media attention, we found seafood mislabeling continues to be prevalent.  相似文献   
72.
We studied the formation of four nitrogenous DBPs(N-DBPs) classes(haloacetonitriles,halonitromethanes, haloacetamides, and N-nitrosamines), as well as trihalomethanes and total organic halogen(TOX), after chlorination or chloramination of source waters. We also evaluated the relative and additive toxicity of N-DBPs and water treatment options for minimisation of N-DBPs. The formation of halonitromethanes, haloacetamides, and N-nitrosamines was higher after chloramination and positively correlated with dissolved organic nitrogen or total nitrogen. N-DBPs were major contributors to the toxicity of both chlorinated and chloraminated waters. The strong correlation between bromide concentration and the overall calculated DBP additive toxicity for both chlorinated and chloraminated source waters demonstrated that formation of brominated haloacetonitriles was the main contributor to toxicity. Ozone–biological activated carbon treatment was not effective in removing N-DBP precursors. The occurrence and formation of N-DBPs should be investigated on a case-by-case basis, especially where advanced water treatment processes are being considered to minimise their formation in drinking waters, and where chloramination is used for final disinfection.  相似文献   
73.
This study aimed to assess soil quality by chemical and ecotoxicological investigations and to check the correspondence between soil metal concentrations and ecotoxicity. For these purposes, surface soils collected at four adjacent roadside urban parks and at a former industrial area were characterized for C/N, organic matter content, texture, and pH. Cr, Cu, Ni and Pb, chosen among the most representative soil metal contaminants, were measured as total content and as available and water soluble fractions. In addition, the total concentrations of the investigated metals were used to calculate two chemical indices: the contamination and the potential ecological risk factors. The toxicity of the investigated soils was evaluated by an ecotoxicity test battery carried out on both soil samples (Vibrio fischeri, Heterocypris incongruens and Sinapis alba) and elutriates (Vibrio fischeri, Daphnia magna and Selenastrum capricornutum). The findings, both by the chemical and ecotoxicological approaches, would suggest that the soils with high metal contamination pose ecological risks. On the other hand, moderately metal contaminated soils did not exclude soil ecotoxicity. In fact, toxic effects were also highlighted in soils with low metal content, toxicity being affected by metal availability and soil characteristics. Moreover, the results suggest the importance of using a battery of tests to assess soil ecotoxicity.  相似文献   
74.
The potential for human and ecological toxicity associated with nanomaterials is a growing area of investigation. In mammalian cells, nanoparticles have been shown to induce inflammation and oxidative stress, and changes in cell signalling and gene expression. As the nanotechnology industries increase production, nanoscale products and by products will enter the aquatic environment, posing a possible threat to aquatic organisms. In particular, filter-feeding organisms may represent a unique target group for nanoparticle toxicology. In this work, the effects of commercial nanosized carbon black (NCB) on the immune cells, the hemocytes, of the bivalve mollusc Mytilus, and the possible mechanisms involved were investigated. The results demonstrate that NCB (1, 5, and 10 microg/ml), did not induce significant lysosomal membrane destabilization, as evaluated by the NR retention time assay. A concentration-dependent uptake of NCB by hemocytes was observed and it was associated by a rapid increase in extracellular lysozyme release, extracellular oxyradical production, and nitric oxide (NO) release. Moreover, at the highest concentration tested, NCB induced significant changes in mitochondrial parameters (decrease mitochondrial mass/number and membrane potential), as evaluated by flow cytometry. The effects of NCB were mediated by rapid activation of the stress-activated MAPKs (Mitogen Activated Protein Kinases) p38 and JNKs, that play a key role in immune and inflammatory responses. The results demonstrate that in mussel hemocytes like in mammalian cells NCB exposure can induce inflammatory processes, and indicate that bivalve immunocytes can represent a suitable model for investigating the effects and modes of action of nanoparticles in the cells of aquatic invertebrates.  相似文献   
75.
76.
The aim of this article is to shed new light on which dimensions compose sustainable purchase intention (SPI) with the purpose of understanding what moves consumers to a potentially more sustainable behaviour. Even though several studies have researched which factors influence consumer’s intention to buy in a more sustainable way, no comparable research in consumer behaviour was found studying these dimensions in a triple bottom line perspective (profit, people, and planet) that could also provide future corporate and academic applications. Therefore, this article proposes a new construct – Consumers’ Perception on SPI, defined using the C-OAR-SE procedure and measured using exploratory and confirmatory factor analysis using two different samples. In-depth interviews and online survey to actual consumers of sustainable products were undertaken in partnership with a sustainable project using its database, guaranteeing that real consumers’ perceptions were gathered for this study. The construct is proposed with two dimensions (measured by nine items): Accessibility (including facets such as product lower pricing, availability in stores, and being sold within a convenient proximity to home) and Trust (including consumers needs such as: to get to know and trust products through understanding the labels; to have had good experiences in the past or simply to have new trial opportunities). Theoretical and practical implications of the findings are also discussed.  相似文献   
77.
Short-beaked common dolphins (Delphinus delphis) and Atlantic spotted dolphins (Stenella frontalis) are the two most abundant cetacean species in the oceanic waters of Madeira and the Azores. They are of similar size, occur in similar habitats and are regularly observed in mixed-species groups to forage together. Genetic analyses suggested that, within each species, dolphins ranging around both archipelagos belong to the same panmictic population. We tested the hypotheses that (1) within each species, individuals from the two archipelagos belong to a single ecological stock; (2) between species, common and spotted dolphins have distinct trophic niches; using fatty acid (FA) and stable isotope (SI) analyses. Fatty acids and stable isotopes were analysed from 86 blubber and 150 skin samples of free-ranging dolphins, respectively. Sex-related differences were not significant, except for common dolphin FA profiles. In S. frontalis, FA and SI differences between archipelagos suggested that individuals belonged to different ecological stocks, despite the existence of gene flow between the two archipelagos. In D. delphis, differences were more pronounced, but it was not possible to distinguish between stock structure and a seasonal effect, due to differential sampling periods in the Azores and Madeira. Inter-specific comparisons were restricted to the Azores where all samples were collected during summer. Differences in FA proportions, noticeably for FA of dietary origin, as well as in nitrogen SI profiles, confirmed that both species feed on distinct resources. This study emphasizes the need for an integrated approach including both genetic and biochemical analyses for stock assessment, especially in wide-ranging marine top predators.  相似文献   
78.
Gender differences in oral cocaine hepatotoxicity have been observed and lipopolysaccharide (LPS) was shown to potentiate cocaine hepatotoxicity in male CF-1 mice. Since cocaine and LPS inflict hepatocellular damage through the production of harmful reactive species, the role of cyclooxygenase-2 (COX-2) in gender-dependent cocaine hepatotoxicity was investigated. COX-2 increases nitric oxide (NO) synthesis and pro-inflammatory mediator production in response to hepatocellular insult. Male and female CF-1 mice were orally administered 20 mg kg?1 cocaine hydrochloride once daily for 7 days. Four hours after the last cocaine administration, the mice received 12 × 106 EU LPS intraperitoneally (cocaine + LPS). Mice receiving meloxicam (7.5 mg kg?1, p.o.), a selective COX-2 inhibitor, were pretreated 1 h before each cocaine administration. Meloxicam prevented liver damage in males produced by cocaine and cocaine + LPS as evidenced by microscopic appearance and biochemical indices equivalent to saline treatment. Acetaminophen (APAP) was administered orally as a positive control which shows no gender dependency and elicited a hepatotoxic response in both males and females. Altered biochemical indices suggest that COX-2 is activated, possibly to a greater extent in females versus males in APAP-induced hepatotoxicity. Meloxicam prevented all oxidative stress changes induced in males following APAP. The results suggest that the induction of COX-2 is responsible, in part, for cocaine hepatotoxicity with and without LPS exposure in male mice.  相似文献   
79.
SUMMARY

The paper outlines some main features of chaos theory. Examples of chaotic systems in society and the environment are given. Spontaneous interaction of components, without being planned or directed, is known as ‘self-organising behaviour’. Chaos is an essential aspect of this self organisation, occurring in many forms. A chaotic system is defined as one that shows sensitivity to initial conditions. If the errors relative to the initial conditions become too great, the system will eventually collapse. Development projects are sensitive to such initial conditions. In particular, two examples in development are outlined in some detail and commented upon. One is the occurrence of a project promoting self-organising systems among the poorest of the poor. The other outlines how rehabilitation after resettlement in a power project has transgressed the ‘edge of chaos’ socio-emotionally, in spite of the socioeconomic development being good.  相似文献   
80.
This study proposes a framework for the collection and management of knowledge related to food security in Canada. This paper has several goals. First, the paper summarizes the current state of food security knowledge in Canada. Second, the paper presents data from an experiment where food security issues were discussed by stakeholders at two fora, the first of which was held in western Canada and the second held in eastern Canada. Finally, based on the notes taken during and feedback received after the fora, this paper suggests a framework for organizing and managing the multiple perspectives and complex types of knowledge about food security and sustainable development from a Canadian context. Two fora were held in Canada where food security issues were presented and discussed by multiple stakeholders. Most provinces in Canada were represented in at least one of the two sessions. Sessions were designed to be informative and interactive; agenda were designed to take advantage of the needs and experiences of multiple stakeholders in both western and eastern regions of Canada. To develop the framework, the sessions were also designed to assess the types of issues and knowledge about food security in Canada. Evidence presented from this experiment supports arguments that food security work must be approached in a collaborative manner, no matter the approach or discipline. Data from fora held in western and eastern regions of Canada indicate a number of specific ways in which those along the food continuum have the desire to share knowledge and enter into partnerships to work toward secure and sustainable food systems. Data also indicate how academia and institutions of higher learning might play a key role in sharing food security-based knowledge. The data from this study suggest that academia could play a leadership role in collecting and sharing information about food security-based knowledge from all disciplinary approaches that could help collaborative in addressing the complexity of food security challenges. The framework developed in this paper could provide the guide for organizing knowledge about food security and sustainable development. The framework could be used as a map to guide understanding about the different ways in which food security can be approached and understood; this could help reduce tensions among partners in projects where a wide variety of experiences are attempting to work collaboratively. The two food security fora brought together stakeholders with specialized knowledge about food security in a Canadian context. The analysis of data arising from the fora permitted unique insights to arise about the nature of knowledge by region. The data in this study also allowed us to build a framework for food security knowledge from these regional knowledge bases. This paper suggests that academia actively take a leadership role and openly share knowledge about food security. Open sharing of knowledge will help collaborates in dealing with complex food security issues understand in-depth other approaches; this sharing may help to make explicit the tensions that arise during collaborative work.  相似文献   
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