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61.
Behavioral genomics of honeybee foraging and nest defense 总被引:9,自引:1,他引:8
Hunt GJ Amdam GV Schlipalius D Emore C Sardesai N Williams CE Rueppell O Guzmán-Novoa E Arechavaleta-Velasco M Chandra S Fondrk MK Beye M Page RE 《Die Naturwissenschaften》2007,94(4):247-267
The honeybee has been the most important insect species for study of social behavior. The recently released draft genomic
sequence for the bee will accelerate honeybee behavioral genetics. Although we lack sufficient tools to manipulate this genome
easily, quantitative trait loci (QTLs) that influence natural variation in behavior have been identified and tested for their
effects on correlated behavioral traits. We review what is known about the genetics and physiology of two behavioral traits
in honeybees, foraging specialization (pollen versus nectar), and defensive behavior, and present evidence that map-based
cloning of genes is more feasible in the bee than in other metazoans. We also present bioinformatic analyses of candidate
genes within QTL confidence intervals (CIs). The high recombination rate of the bee made it possible to narrow the search
to regions containing only 17–61 predicted peptides for each QTL, although CIs covered large genetic distances. Knowledge
of correlated behavioral traits, comparative bioinformatics, and expression assays facilitated evaluation of candidate genes.
An overrepresentation of genes involved in ovarian development and insulin-like signaling components within pollen foraging
QTL regions suggests that an ancestral reproductive gene network was co-opted during the evolution of foraging specialization.
The major QTL influencing defensive/aggressive behavior contains orthologs of genes involved in central nervous system activity
and neurogenesis. Candidates at the other two defensive-behavior QTLs include modulators of sensory signaling (Am5HT
7
serotonin receptor, AmArr4 arrestin, and GABA-B-R1 receptor). These studies are the first step in linking natural variation in honeybee social behavior
to the identification of underlying genes. 相似文献
62.
Ernesto Di Maio Raed Mali Salvatore Iannace 《Journal of Polymers and the Environment》2010,18(4):626-633
Conventional direct melt mixing technology was investigated on zein and kafirin, two vegetable proteins extracted, respectively,
from maize and sorghum. A lab scale internal mixer has been used to thoroughly study the thermo-plasticization process of
the proteins with several plasticizers. Different compositions were investigated under different processing conditions. In
particular, the lengthy procedures of forming the protein/solvent/plasticizer solution followed by drying or the protein/plasticizer
emulsion followed by the precipitation of the extrudable resin, reported in the literature for these systems, were avoided
and the protein and plasticizer were directly fed into the mixer to obtain a plastic-like material. The effect of plasticizer
type and content and mixing process variables on the mechanical properties was analyzed. Compression molded slabs were transparent,
strong and flexible, with properties similar to the cast films reported in the literature, prepared with the same type of
plasticizers. However, lower plasticizer content was sufficient to produce equally flexible films, proving an enhanced plasticization
efficiency of the mixing process, as compared to casting. 相似文献
63.
Hector G. Riveros Alfredo Alba Pilar Ovalle Beatriz Silva Ernesto Sandoval 《Journal of the Air & Waste Management Association (1995)》2013,63(5):459-462
ABSTRACT From the analysis of data of the Inspection/Maintenance (I/M) program, and of the long-term trend of ambient CO concentrations in Mexico City, it is inferred that three-way catalysts (TWCs) have a 45% efficiency, well below the expected 90% value. The most probable causes are sulfur poisoning, lead contamination, and ceramic breakage due to bumps and potholes on the streets. Also, we have found a ratio between the average daily peak value of atmospheric CO and gasoline consumption: (11 ± 1) ppbCO/MLm (million liters of gasoline per month) in 1988 decaying to (10 ±1) in 1991 for Mexico City before the introduction of TWCs. In addition, we found a correlation between the monthly averages of CO daily peak and meteorological variables, explaining most of the seasonal changes using only the intensity of the inversion layer and surface wind speed. 相似文献
64.
Tracking the evolution of research in waste recycling science (WRS) can be valuable for environmental agencies, as well as for recycling businesses. Maps of science are visual, easily readable representations of the cognitive structure of a branch of science, a particular area of research or the global spectrum of scientific production. They are generally built upon evidence collected from reliable sources of information, such as patent and scientific publication databases. This study uses the methodology developed by Rafols et al. (2010) to make a "double overlay map" of WRS upon a basemap reflecting the cognitive structure of all journal-published science, for the years 2005 and 2010. The analysis has taken into account the cognitive areas where WRS articles are published and the areas from where it takes its intellectual nourishing, paying special attention to the growing trends of the key areas. Interpretation of results lead to the conclusion that extraction of energy from waste will probably be an important research topic in the future, along with developments in general chemistry and chemical engineering oriented to the recovery of valuable materials from waste. Agricultural and material sciences, together with the combined economics, politics and geography field, are areas with which WRS shows a relevant and ever increasing cognitive relationship. 相似文献
65.
Ernesto Bosatta 《Ecological modelling》1981,13(4):237-245
This is the second part of a study aimed at achieving some qualitative understanding of the stability properties of the root-microorganism soil system. The first part concentrated on the effect on this stability of different patterns of either nitrogen- or energy-limiting conditions. To this end, a mathematical model has been developed. The model, the theory and some results of the first part are extended here to more complex situations.A factor is first defined to measure the likelihood of the danger of extinction of the roots. It is found that this danger is increased with increasing specific mortality rates, decreasing nitrogen input and/or increasing periods of time during which decomposers are nitrogen-limited. It is also found that the danger of extinction is not directly proportional to absolute nitrogen losses from the system. Some possible explanations in terms of compensatory mechanisms of the roots are discussed. 相似文献
66.
Pollination is an ecological process that provides important services to humans. Pollination service in agroecosystems depends on several factors, including the land management systems used by farmers. Here we focused on the effects of insect pollinator diversity on coffee fruit production along a gradient of management systems in central Veracruz, Mexico. The gradient ranged from low environmental impact management systems (the native forest is not completely removed) to high environmental impact management systems (the native forest is completely removed). We hypothesized that pollinator diversity should be higher in low-impact systems. Then, if fruit production is positively related to pollinator diversity, plantations with low-impact management systems should display higher fruit production than plantations with high-impact management systems. We used observational and experimental data to test this hypothesis. Our results indicated that low-impact management systems have higher species richness and relative diversity (measured with the Shannon-Wiener diversity index) of pollinators than high-impact management systems. In all cases, fruit production was positively related with species richness and diversity of pollinators. Moreover, fruit production was higher in low-impact than in high-impact management systems. These results suggest that the diversity of insect pollinators can be influenced by the management system applied by farmers, and that such effects may have strong consequences on coffee fruit production. 相似文献