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41.
Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is an omnivorous generalist predator which is augmentatively released and conserved for control of whiteflies (Hemiptera: Aleyrodidae) and Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in tomato crops. Eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) are often provided as factitious prey to improve the establishment of N. tenuis after its release. We first tested different amounts of E. kuehniella eggs per plant to optimize N. tenuis establishment and then investigated whether the amount of eggs that optimized N. tenuis establishment might be reduced by adding sugars (hydrocapsules filled with 0.5 m sucrose) under walk‐in cage and commercial greenhouse conditions. These experiments demonstrated that the addition of sugar to the diet of N. tenuis could half the amount of E. kuehniella eggs required to establish N. tenuis. Under greenhouse conditions, the progeny of N. tenuis per plant did not differ significantly between E. kuehniella alone or the half amount of E. kuehniella plus hydrocapsules. These results demonstrated that the sugar could partially substitute for E. kuehniella eggs improve establishment of N. tenuis and suggest that natural sugars such as nectar and honeydew might also beneficial.  相似文献   
42.
Adult Trichoptera were caught from September 1999 to September 2000 at the Thaya River at Hardegg, Lower Austria, using a Jermy-type light trap. From a total of 11,711 specimens caught, the most abundant species were Psychomyia pusilla (Fabricius ), Lepidostoma hirtum (Fabricius ), Lasiocephala basalis (Kolenati ), Agapetus ochripes Curtis and Sericostoma flavicorne Schneider . In nine out of the eleven most abundant species the sex ratios significantly differed from 1:1, with an excess of females. Of the meteorological parameters tested, only the effect of air temperature was significant. An upstream shift of faunal zonation patterns from epipotamon to meta- and hyporhithron could be detected at the station which is influenced by hypolimnetic water release.  相似文献   
43.
Mercury-containing products release mercury (Hg) throughout their lifecycles, frequently in ways that are difficult to measure directly. Therefore, there are considerable uncertainties about the magnitude of mercury releases associated with products, about which products and which release pathways contribute the most to mercury releases, and about the likely impact on mercury releases of various possible interventions in the mercury content of products or in the management of mercury-containing wastes. This article presents an effort to use substance flow analysis to develop improved estimates of the environmental releases caused by mercury-containing products and to provide policy-makers with a better understanding of opportunities for reducing releases of mercury caused by products.  相似文献   
44.
King  Jackie  Cambray  Jim A.  Dean Impson  N. 《Hydrobiologia》1998,384(1-3):245-265
In South Africa, modified flow regimes designed to maintain ecosystem functioning at some pre-determined level are recommended for all rivers involved in major water-resource developments. One component of such flow regimes of special interest in the winter-rainfall region of the country is the small pulses of higher flow that occur in the dry season (November–April), here called freshes. Research was carried out in the Olifants River, in the winter-rainfall region of South Africa, on the link between freshes and spawning of an endemic, vulnerable cyprinid, the Clanwilliam yellowfish Barbus capensis. Experimental releases from Clanwilliam Dam on the Olifants River in a previous year showed that a greater than usual spawning success, assessed by larval recruitment levels, was correlated with hypolimnetic freshes released during the species' breeding season (October–January). In the study reported on here, a hypolimnetic fresh of the same size, duration and timing as those linked with successful spawning failed to induce spawning. Differences in the thermal regime of water releases appeared to be responsible. Two warm (19–21 °C), epilimnetic freshes of 15 hours duration were then released, and correlated with fish moving onto the spawn beds and exhibiting pre-spawning behaviour. However, the fish moved downstream away from the spawn beds when cold (16–18 °C) hypolimnetic baseflows were released for 15 hours between the two epilimnetic freshes and continually after the second one. The presence of free embryos and larval B. capensis indicated, from their developmental stages, that spawning had probably occurred before the experimental releases began, when warm (21–23 °C) epilimnetic water was spilling over the dam, and had halted once spillage stopped and hypolimnetic releases began. Indeed, the presence of dead and deformed young suggested that the cold water may have had a detrimental affect on those spawned during the earlier warmer spell. A summary table details the conditions, including the hydraulic characteristics of the spawn beds, believed to induce spawning and support early life stages of B. capensis. It is concluded that freshes released from Clanwilliam Dam at the appropriate time (October–January) should be able to increase spawning success of B. capensis, but only if the water temperature at the spawn site is at or above 19 °C and stable or rising. However, successful spawning will not necessarily lead to high recruitment if water temperatures are not then maintained at appropriate levels for some time for development of the embryos and larvae. This implies that additional epilimnetic releases will be required following critical trigger flows.  相似文献   
45.
This study proposes methods to improve data mining workflows for modeling chemical manufacturing life cycle inventory. Secondary data sources can provide valuable information about environmental releases during chemical manufacturing. However, the often facility‐level nature of the data challenges their utility for modeling specific processes and can impact the quality of the resulting inventory. First, a thorough data source analysis is performed to establish data quality scoring and create filtering rules to resolve data selection issues when source and species overlaps arise. A method is then introduced to develop context‐based filter rules that leverage process metadata within data sources to improve how facility air releases are attributed to specific processes and increase the technological correlation and completeness of the inventory. Finally, a sanitization method is demonstrated to improve data quality by minimizing the exclusion of confidential business information (CBI). The viability of the methods is explored using case studies of cumene and sodium hydroxide production in the United States. The attribution of air releases using process context enables more sophisticated filtering to remove unnecessary flows from the inventory. The ability to sanitize and incorporate CBI is promising because it increases the sample size, and therefore representativeness, when constructing geographically averaged inventories. Future work will focus on expanding the application of context‐based data filtering to other types and sources of environmental data.  相似文献   
46.
Questions: Do the number, duration and magnitude of growth releases following formation of natural, fine‐scale canopy gaps differ among shade‐tolerant Thuja plicata, Tsuga heterophylla and Abies amabilis? What is the relative importance of tree‐level and gap‐level variables in predicting the magnitude and duration of releases? What does this tell us about mechanisms of tree species coexistence in such old‐growth forests? Location: Coastal British Columbia, Canada. Methods: We estimated the timing of formation of 20 gaps using dendroecological techniques and extracted increment cores from all three species growing around or within gaps. Using a species‐ and ecosystem‐specific release‐detection method, we determined the number of trees experiencing a release following gap formation. We quantified the duration and magnitude of individual releases and estimated the influence of tree‐level and gap‐level variables on these release attributes. Results: Eighty‐seven per cent (304 of 348) of all trees experienced a release following gap formation. T. heterophylla and A. amabilis experienced higher magnitude and longer duration releases than T. plicata. The effect of diameter on the duration of releases varied among species, with T. heterophylla and A. amabilis experiencing decreasing, and T. plicata experiencing increasing, duration of releases with increasing diameter. The effect of growth rate prior to a release on the magnitude of releases varied among trees of different diameters, with the slowest growing and smallest individuals of all species experiencing the most intensive releases. Conclusions: Our results provide detailed information on the number, duration and magnitude of growth releases of the above three species following gap formation. Differences in response to canopy gaps suggest differences in how these species ascend to the canopy strata. T. plicata may be less dependent on gaps to reach the canopy. Differing strategies for ascending to the canopy strata may be important in facilitating coexistence of these three species in old‐growth forests of coastal British Columbia.  相似文献   
47.
β‐Cyclodextrin (β‐CD) hydrogel was prepared in a strong alkali condition using epichlorohydrin (EPI) as a cross‐linker, where the molar ratios of EPI to β‐CD were 8:1, 10:1, and 15:1. In order to endow a pH sensitivity to the hydrogel, naphthaleneacetic acid (NAA) was loaded in the hydrogel by taking advantage of its hydrophobic interaction with the cavities of β‐CD. The releases of blue dextran (a water‐soluble dye) from the hydrogels were promoted, as the pHs of the media increased. When the molar ratio of EPI to β‐CD was lower, the degrees of release were higher, and the pH dependency of the release became more prominent. In fact, the swelling ratio of the hydrogels having a lower molar ratio of EPI to β‐CD was higher. The higher swelling ratio would account for the higher degree of release and the marked pH sensitivity. Biotechnol. Bioeng. 2010;106: 295–302. © 2010 Wiley Periodicals, Inc.  相似文献   
48.
Restauro-G: A Rapid Genome Re-Annotation System for Comparative Genomics   总被引:1,自引:0,他引:1  
of complete genome sequences submitted directly from sequencing projects are diverse in terms of annotation strategies and update frequencies. These inconsistencies make comparative studies difficult. To allow rapid data preparation of a large number of complete genomes, automation and speed are important for genome re-annotation. Here we introduce an open-source rapid genome re-annotation software system, Restauro-G, specialized for bacterial genomes. Restauro-G re-annotates a genome by similarity searches utilizing the BLASTLike Alignment Tool, referring to protein databases such as UniProt KB, NCBI nr, NCBI COGs, Pfam, and PSORTb. Re-annotation by Restauro-G achieved over 98% accuracy for most bacterial chromosomes in comparison with the original manually curated annotation of EMBL releases. Restauro-G was developed in the generic bioinformatics workbench G-language Genome Analysis Environment and is distributed at http://restauro-g.iab.keio.ac.jp/ under the GNU General Public License.  相似文献   
49.
High frequency (200kHz) echosounding was used to determine vertical structuring and seasonal changes in the depth distributions of limnetic fish in three New Zealand lakes. Juvenile (f.l. 30–50 mm) and large-sized (f.l. 50–80 mm) smelt Retropinna retropinna were segregated into discrete layers by depth in all three lakes throughout the year. Larval and post-larval bullies Gobiomorphus cotidianus (f.l. 8–20 mm) formed a further layer between the layers of small and iarge-sized smelt. Although the depths of the large-sized smelt and bully layers changed on a seasonal basis, vertical segregation between the three layers of fish persisted throughout the year, even when the lakes were homothermal. Seasonal movements of fish were disrupted by the autumnal deoxygenation of the hypolimnion in Lake Rotoiti. The schools of large-sized smelt were forced to ascend towards the layer of bullies, but segregation between these smelt and the bullies was maintained as the smelt occupied a much reduced depth range above the hypolimnion, and just below the bullies. The winter descent of bullies, which precedes their transition to a benthic existence failed to occur in Lake Rotoiti, even though the lake was fully mixed at this time.  相似文献   
50.
Exposure of Eriopis connexa (Germar) to pyrethroid residues in agroecosystems has resulted in selection for resistance (R). Pyrethroid resistance allows E. connexa to survive lambda-cyhalothrin applications. Following a field release of E. connexa, development of resistance in an incipient population may depend on three major factors such as the maintenance of: (i) selection pressure, (ii) frequency of mating with susceptible phenotypes (S) and (iii) differential reproductive performance due to the fitness costs associated with resistance. To investigate the potential effects of these three factors on the development of pyrethroid resistance by progeny of field released E. connexa, our experiments included panmictic mating between R and S phenotypes, followed by descendant rearing with and without insecticide selection pressure, reselection and determination of resistance levels. In addition, we measured the reproductive performance of the parental R and S phenotypes and their descendants to assess the cost of resistance after crossing and reselection. Survival of R × S descendants exposed to lambda-cyhalothrin was reduced across successive generations in the absence of selection pressure, but still enhanced after four generations indicating the persistent presence of resistant phenotypes in the population. Under selection pressure with exposure to lambda-cyhalothrin applied at label rates, descendant survival was >50%. Fecundity and survival were higher in the first-generation of crossed R × S females, but higher fecundity was not sustained after reselection. Adults of the R population exhibited a fitness cost, reduced longevity, when compared to S phenotypes and R × S crossed populations. Therefore, resistance maintenance in E. connexa after release will depend on selection pressures imposed by insecticide exposure. In the absence of selection pressure, the phenotype for resistance was reduced, but not completely lost. Further, resistant phenotypes can be reselected following insecticide exposure and this can explain, in part, the high frequency of field-evolved resistance to lambda-cyhalothrin in E. connexa.  相似文献   
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