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41.
Accidents produce external pressures on companies leading to new regulations and renegotiation of enforcement of regulations. Our perspective is institutional with a focus on the extended dialogue among regulators and the industry. The empirical focus is offshore oil and gas production, deep sea and coastal fisheries, and maritime transportation with a segment of older bulk carriers. The findings are that structural characteristics of both the industries and the regulatory regime determine the interactions between the regulated and the regulator. The paper illustrates that in industrial sectors where hazards and risks are visible and of public interest, it is easier to implement regulations through outside pressure from regulators and other stakeholders such as internationally organised unions. 相似文献
42.
Erica M. Tennenhouse Robert B. Weladji Øystein Holand Knut H. Røed Mauri Nieminen 《Behavioral ecology and sociobiology》2011,65(2):287-295
In polygynous species, males devote considerable effort to reproduction during the rut. Both the number of females in the
mating group and the ratio of sexually mature males to sexually mature females [adult sex ratio (ASR)] are expected to affect
the amount of effort a male devotes to reproductive activities. We predicted the reproductive effort of dominant male reindeer,
measured as relative mass loss, proportions of active reproductive behaviors, and frequencies of agonistic behaviors would
(1) increase with an increasing number of females in the mating group and eventually level off, and (2) exhibit a dome shape
with respect to ASR in the mating group. We tested these predictions using 12 years of data collected from semi-domesticated
reindeer in northern Finland. We found a positive relationship between relative mass loss and the mean number of females in
the mating group for mature, but not young males. The relationship between the proportion of active reproductive behaviors
performed by mature males and the mean number of females in the group was quadratic while agonistic behaviors of mature males
increased with the increasing female group size. We also found that active reproductive behaviors decreased with a rising
mating group ASR for mature males; whereas, young males performed more agonistic behaviors as group ASR increased. Our results
point to age-specific patterns of mass loss and activity during the mating season. They also indicate that both the number
of females and ASR in the mating group are important factors in determining the level of reproductive effort of dominant male
reindeer. 相似文献
43.
The aim of this study was to examine the effects of litter size and parity on sibling competition, piglet survival, and weight
gain. It was predicted that competition for teats would increase with increasing litter size, resulting in a higher mortality
due to maternal infanticide (i.e., crushing) and starvation, thus keeping the number of surviving piglets constant. We predicted
negative effects on weight gain with increasing litter size. Based on maternal investment theory, we also predicted that piglet
mortality would be higher for litters born late in a sow's life and thus that the number of surviving piglets would be higher
in early litters. As predicted, piglet mortality increased with increasing litter size both due to an increased proportion
of crushed piglets, where most of them failed in the teat competition, and due to starvation caused by increased sibling competition,
resulting in a constant number of survivors. Piglet weight at day 1 and growth until weaning also declined with increasing
litter size. Sows in parity four had higher piglet mortality due to starvation, but the number of surviving piglets was not
affected by parity. In conclusion, piglet mortality caused by maternal crushing of piglets, many of which had no teat success,
and starvation caused by sibling competition, increased with increasing litter size for most sow parities. The constant number
of surviving piglets at the time of weaning suggests that 10 to 11 piglets could be close to the upper limit that the domestic
sow is capable of taking care of. 相似文献
44.
The optimal defense theory (ODT) deals with defensive compounds improving fitness of a particular organism. It predicts that these compounds are allocated in proportion to the risk for a specific plant tissue being attacked and this tissue's value for plant fitness. As the benefit of defense cannot easily be measured in plants, the empirical evidence for ODT is limited. However, lichens are unique in the sense that their carbon-based secondary compounds can nondestructively be removed or reduced in concentration by acetone rinsing. By using such an extraction protocol, which is lethal to plants, we have tested the ODT by studying lichens instead of plants as photosynthetically active organisms. Prior to acetone rinsing, we found five times higher concentration of meta-scrobiculin in the reproductive parts (soralia) of Lobaria scrobiculata compared to somatic parts of this foliose epiphytic lichen species. At this stage, the lichen-feeding snail Cochlodina laminata avoided the soralia. However, after removal of secondary compounds, the snail instead preferred the soralia. In this way, we have successfully shown that grazing pattern inversely reflects the partitioning of the secondary compounds that have a documented deterring effect. Thus our study provides strong and novel evidence for the ODT. 相似文献
45.
46.
Elshaghabee Fouad M. F. Rokana Namita Panwar Harsh Heller Knut J. Schrezenmeir Jürgen 《Environmental Chemistry Letters》2019,17(4):1553-1563
Environmental Chemistry Letters - Non-alcoholic fatty liver disease (NAFLD) is characterized by an increase in fat content of liver cells, which is independent from alcohol intake. Here, we review... 相似文献
47.
The local branches of the Russian Forestry Service, the leskhozy, were known for their efficiency and management skills in the Soviet era and were one of the very few community-based Soviet-type institutions to survive the transition. This article examines the role of the leskhozy in the new market economy. Our analysis is based on data from interviews with informants attached to the forestry sector in the Murmansk area. In some cases their knowledge of the leskhozy stretches back to the emergence of the system in 1947. Our principal finding is that the struggle to survive as a federal body in the current legal and economic climate is forcing the leskhozy to relegate sustainable forestry management, presumably their primary raison dêtre, to the lower portions of their list of priorities. Several consequences result. There is a heightened incidence of illegal logging, and corruption informs the allocation of forest areas to private interests. Stumpage prices have plummeted as timber from subsidized commercial cutting (ostensibly sanitary cutting or thinning) has flooded the markets. The root cause of these tribulations lies with the market-based harvesting permit system. Its introduction in the 1990s did little to eliminate the self-seeking practices of the old Soviet forestry management hierarchies. In the free market, local forestry managers can turn their dual responsibilities to their own advantage inasmuch as they control the allocation of harvesting permits while at the same time controlling logging practices. 相似文献
48.
Soler JJ Peralta-Sánchez JM Flensted-Jensen E Martín-Platero AM Møller AP 《Die Naturwissenschaften》2011,98(9):807-813
Fitness benefits associated with the development of a costly immune system would include not only self-protection against
pathogenic microorganisms but also protection of host offspring if it reduces the probability and the rate of vertical transmission
of microorganisms. This possibility predicts a negative relationship between probabilities of vertical transmission of symbionts
and level of immune response that we here explore inter-specifically. We estimated eggshell bacterial loads by culturing heterotrophic
bacteria, Enterococcus, Staphylococcus and Enterobacteriaceae on the eggshells of 29 species of birds as a proxy of vertical transmission of bacteria from mother to offspring. For this
pool of species, we also estimated innate immune response (natural antibody and complement (lysis)) of adults, which constitute
the main defence against bacterial infection. Multivariate general linear models revealed the predicted negative association
between natural antibodies and density of bacteria on the eggshell of 19 species of birds for which we sampled the eggs in
more than one nest. Univariate analyses revealed significant associations for heterotrophic bacteria and for Enterobacteriaceae, a group of bacteria that includes important pathogens of avian embryos. Therefore, these results suggest a possible trans-generational
benefit of developing a strong immune system by reducing vertical transmission of pathogens. 相似文献
49.
Emissions trading schemes where allocations are based on updated baseline emissions give firms less incentive to reduce emissions for a given quota (or allowance) price. Nevertheless, according to Böhringer and Lange [On the design of optimal grandfathering schemes for emission allowances, Europ. Econ. Rev. 49 (2005) 2041–2055], such allocation schemes are cost-effective if the system is closed and allocation rules are identical across firms. In this paper, we show that the cost-effective solution may be infeasible if marginal abatement costs grow too fast. Moreover, if a price cap or banking/borrowing is introduced, the abatement profile is no longer the same as in the case with an auction (or lump-sum allocation). In addition, we show that with allocation based on updated emissions, the quota price will always exceed marginal abatement costs, possibly misguiding policy makers and investors about abatement costs. Numerical simulations indicate that the quota price most likely will be several times higher than marginal abatement costs, unless a significant share of allowances is auctioned. 相似文献
50.
Schuster JK Gioia R Harner T Lee SC Breivik K Jones KC 《Journal of environmental monitoring : JEM》2012,14(1):71-78
Two field studies were conducted for one year using sorbent-impregnated polyurethane foam (SIP) disks for PCB and PBDE air sampling. SIP disks were introduced by Shoeib et al. (2008) as an alternative passive air sampling medium to the polyurethane foam (PUF) disk and have the advantage of a higher holding capacity for organic chemicals. The first study on SIP disks confirmed their application for measuring volatile perfluorinated compounds (PFCs) and their ability to maintain time-integrated (linear) air sampling. In this study, the suitability of the SIP disks for long-term sampling of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and hexachlorobenzene (HCB) was assessed. SIP disks were deployed at a rural site in the UK and harvested after periods ranging from 35-350 days. Atmospheric POP concentrations were monitored with a high-volume air sampler during the deployment period. Linear uptake was observed for all monitored PCBs and PBDEs over the full exposure time. Air-sampler equilibrium was observed for HCB after 6 months. In a second field study, SIP disks were deployed for one year at 10 sites on a latitudinal transect in the UK and Norway, at which air sampling has been undertaken previously with different passive air sampling media since 1994. The estimated concentrations and spatial distributions derived from the SIP disks were largely in agreement with previously reported data. 相似文献