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61.
Glenda Dias Karla S. C. Yotoko Luiz F. Gomes José Lino-Neto 《Die Naturwissenschaften》2012,99(9):773-777
Several species of Tenebrionidae are stored-grain pests. Since they belong to a specious family, the systematics of these beetles is still in doubt. In insects, spermatogenesis and the spermatozoa exhibit great diversity, and are therefore commonly used in phylogenetic and taxonomic analyses. During the spermatogenetic process in these organisms, the cells originating from a single spermatogonium develop synchronically in groups referred to as cysts. At the end of this process, there is usually only one sperm bundle per cyst, with all the cells in the same orientation. This paper details the spermiogenesis of the tenebrionid beetles Tenebrio molitor, Zophobas confusa, Tribolium castaneum and Palembus dermestoides using whole mount and histological sections of the cysts. In these species, spermatogenesis is similar to that which occurs in most insects. However, during spermiogenesis, the nuclei of the spermatids migrate to two opposite regions at the periphery of the cyst, leading to the uncommon formation of two bundles of spermatozoa per cyst. This feature is possibly an apomorphy for Tenebrionidae. 相似文献
62.
Camilo-Cotrim Carlos Filipe Bailão Elisa Flávia Luiz Cardoso Ondei Luciana Souza Carneiro Fernanda Melo Almeida Luciane Madureira 《Environmental science and pollution research international》2022,29(32):48088-48104
Environmental Science and Pollution Research - The increasing use of pesticides has caused global concerns about the toxic effects and adverse consequences of pesticides on humans and the... 相似文献
63.
Jarvin Mariyadhas Kumar Sundararajan Ashok Rosaline Daniel Rani Foletto Edson Luiz Dotto Guilherme Luiz Inbanathan Savariroyan Stephen Rajkumar 《Environmental science and pollution research international》2022,29(38):57330-57344
Environmental Science and Pollution Research - In this work, Ag-doped ZnO nanoparticles (NPs) were synthesized by a simple green method using a toxic agent-free route for photocatalytic purposes,... 相似文献
64.
Fagundes Pâmela Carniel Thaís Karoline Hall Monique Canal Colpani Gustavo Lopes Silva Luciano Luiz Zanetti Micheli de Mello Josiane Maria Muneron Dalcanton Francieli Fiori Márcio Antônio 《Journal of Polymers and the Environment》2022,30(1):125-135
Journal of Polymers and the Environment - The objective of this study was to obtain and characterize Nerol essential oil encapsulated in PCL. The miniemulsion and solvent evaporation method was... 相似文献
65.
Carlos Rosano-Peña Patricia Guarnieri André Luiz Marques Serrano Herbert Kimura 《国际发展与全球生态学杂志》2014,21(3):210-222
The social and environmental impacts caused by the modernization of Brazilian agribusiness have evoked a growing interest in the search of balance between social-economics development and the adequate use of natural resources, driving the country to sustainable development. Therefore, the main aim of this article is to estimate a set of indicators of relative efficiency in the Brazilian agricultural sector, which satisfy the concept of Pareto optimality, potentiates simultaneously both economic, ecological dimensions and social functions. To reach this purpose, the method of directional distance functions and data envelopment analysis was applied. These indicators confirm, in different ways, the hypothesis that it is possible to perform consistent productive strategies with the maximization of social welfare, despite the apparent antagonism among these three dimensions. In addition, it is shown that efficient Brazilian states tend to combine the three dimensions in different ways. Hence, it can be concluded that several equilibrium taken sustainable can be achieved through different actions on poverty and environmental impact reduction without necessarily generating productive inefficiencies. This result can be considered of prominent importance for sustainable development in Brazil and can also serve as a reference in the definition of goals of the plan ‘Brazil without Misery’ and international commitments to reduce Greenhouse Gas – GHG – in Brazil, especially for the 17 inefficient Brazilian states. 相似文献
66.
Anderson Ribeiro Duarte Luiz Duczmal Sabino José Ferreira André Luiz F. Cançado 《Environmental and Ecological Statistics》2010,17(2):203-229
The geographic delineation of irregularly shaped spatial clusters is an ill defined problem. Whenever the spatial scan statistic
is used, some kind of penalty correction needs to be used to avoid clusters’ excessive irregularity and consequent reduction
of power of detection. Geometric compactness and non-connectivity regularity functions have been recently proposed as corrections.
We present a novel internal cohesion regularity function based on the graph topology to penalize the presence of weak links
in candidate clusters. Weak links are defined as relatively unpopulated regions within a cluster, such that their removal
disconnects it. By applying this weak link cohesion function, the most geographically meaningful clusters are sifted through
the immense set of possible irregularly shaped candidate cluster solutions. A multi-objective genetic algorithm (MGA) has
been proposed recently to compute the Pareto-sets of clusters solutions, employing Kulldorff’s spatial scan statistic and
the geometric correction as objective functions. We propose novel MGAs to maximize the spatial scan, the cohesion function
and the geometric function, or combinations of these functions. Numerical tests show that our proposed MGAs has high power
to detect elongated clusters, and present good sensitivity and positive predictive value. The statistical significance of
the clusters in the Pareto-set are estimated through Monte Carlo simulations. Our method distinguishes clearly those geographically
inadequate clusters which are worse from both geometric and internal cohesion viewpoints. Besides, a certain degree of irregularity
of shape is allowed provided that it does not impact internal cohesion. Our method has better power of detection for clusters
satisfying those requirements. We propose a more robust definition of spatial cluster using these concepts. 相似文献
67.
Humberto V. Fajardo Elson Longo Daniela Z. Mezalira Giselle B. Nuernberg Gizelle I. Almerindo André Collasiol Luiz F. D. Probst Irene T. S. Garcia Neftalí L. V. Carreño 《Environmental Chemistry Letters》2010,8(1):79-85
Al2O3, MgO, SiO2 and ZnO-supported nickel catalysts were prepared and evaluated in the ethanol steam reforming for hydrogen production. It
is shown that the catalytic behavior can be influenced depending on the experimental conditions employed and chemical composition
of the catalyst. 相似文献
68.
Ana P. L. Batista Hudson Wallace Pereira Carvalho Gustavo H. P. Luz Paulo F. Q. Martins Maraísa Gonçalves Luiz C. A. Oliveira 《Environmental Chemistry Letters》2010,8(1):63-67
A photocatalyst based on CuO/SiO2 was prepared, and evaluated for the degradation of methylene blue in aqueous medium. The photocatalyst was obtained by calcination
method of copper salt, in the presence of silica. The characterization by XRD, FTIR, and TPR techniques confirmed the formation
of CuO as active phase. SEM studies showed CuO deposited on the surface of SiO2. By ESI-MS, it was demonstrated that the degradation of methylene blue occurs through successive hydroxylations. Photodegradation
assays showed that CuO/SiO2 was efficient for degradation, and that the material worked better in the presence of UV light. 相似文献
69.
Monica Porto Rubem La Laina Porto Luiz Gabriel T. Azevedo 《Journal of the American Water Resources Association》1999,35(3):675-683
ABSTRACT: Brazil is currently facing the challenge of implementing a new water resources management system to promote the rational and sustainable use of the country's waters. This system is based on the following principles of water management: (2) stakeholders' participation; (2) the watershed as the planning and management unit; and (3) the economic value of water. Stakeholders' participation and the involvement of civil society in the decision making process is guaranteed by permanent seats in the watersheds' management committees. These committees are the highest decision level for the establishment of water policy and for planning its use. The executive branch of the committees is the watershed agency or the water agency. This paper presents the recently approved Brazilian water resources management system and discusses the participatory approach followed to validate and to ensure prompt response to decisions regarding water use by all stakeholders. The formulation of the National Water Law (January/1998) was also supported by extensive consultation with civil society, professional associations, state and municipal governments as well as with federal governmental agencies and private sector organizations. It also presents an overview of the formulation of the National Water Law. Finally, as watershed committees have been created and are already operating in a limited number of watersheds, some of the major obstacles to the success of the new system are discussed along with alternatives for overcoming such obstacles. 相似文献
70.
Carlos André Vaz Junior José Luiz de Medeiros Ofélia de Queiroz Fernandes Araújo 《Journal of Loss Prevention in the Process Industries》2010,23(3):462-475
This work presents a time series strategy for detection, location and quantification of leaks in large pipeline systems. The technology has two active components, which operate sequentially: the Detector and the Localizer. The Detector continuously screens real-time data, searching for any anomalies such as leaks, which are detected (or not) depending on their size and position. The Detector is based on auto-regressive multi-input/multi-output (MIMO) ARX predictors with one input filter. Subsequent to successful leak detection, the Localizer is launched to diagnose the leak via estimation of its parameters – diameter and location – using recorded data on a Search Time Window that includes information in the neighborhood of the instant of detection. The Localizer is also an ARX predictor, but with two input processors, the first is a filter for dynamic plant inputs and the second filter processes “parameter signals” of active leaks. The Localizer is developed beforehand via model identification with plant data under the action of known, artificially simulated, leaks. It is, therefore, able to recognize an active pattern of leak parameters, by maximizing the adherence of its predictions to data in the Search Time Window. The proposed detection and location methods were successfully tested in simulated leak scenarios for an industrial naphtha pipeline. 相似文献