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51.
A. Gumbert 《Behavioral ecology and sociobiology》2000,48(1):36-43
It is usually assumed that the choice behavior of bees for floral colors is influenced by innate preferences only for the
first flower visits prior to any experience. After visits to rewarding flowers bees learn to associate their colors with a
reward. This learning process leads to an acquired preference for the trained colors that has been believed to dominate over
previous experiences and over innate preferences. This work investigates how bumble bees (Bombus terrestris) chose among artificial flowers of different colors after they had been extensively trained to other colors. The bees chose
novel colors according to their similarity to the trained color if the trained color was similar to some of the test colors.
This was true also if trained colors and test colors were well distinguished, so their color choice reflected generalization
between colors. If the test colors were so different from the trained color that no generalization took place, choice behavior
was not affected by the trained color and reflected innate preferences. The differences in choice frequencies could not be
explained by physical properties of the test colors other than the dominant wavelength, a parameter taken to reflect hue perception.
Preferred dominant wavelengths correspond to those observed in naive bumble bees and honeybees. Thus bumble bees show innate
preferences for certain colors not only prior to color learning but also after intensive learning when choosing among very
different novel colors. Color choice among similar colors, however, is controlled by generalization from the learned color.
Received: 9 November 1999 / Received in revised form: 19 March 2000 / Accepted: 31 March 2000 相似文献
52.
Trapping and decomposing of color compounds from recycled water by TiO2 coated activated carbon 总被引:1,自引:0,他引:1
Five types of commercially available activated carbons (ACs) were coated with TiO2 nanoparticles prepared using a sol–gel method. Color and trace organics remaining in the actual treated effluent were adsorbed by TiO2 coated ACs. The absorbed organic compounds were then decomposed using a photocatalytic process, and the ACs were regenerated for reuse. The efficiency of the process was assessed by the characterization of true color and A254 (the organics absorption at the wavelength of 254 nm) at the beginning and the end of the experiment. The effects of UV light source, UV irradiation time, hydrogen peroxide and ultrasound on the efficiency of photocatalytic regeneration were also investigated. Significant differences in the efficiency were observed between uncoated ACs and TiO2 coated samples. Among the 5 types of ACs tested, AC-3, AC-4 and their coated ones achieved better efficiency in color and A254 removal, with around 90% or more color and A254 being removed within 1 h of treatment. The data obtained in this study also demonstrated that the photocatalytic process was effective for decomposing the adsorbed compounds and regenerating the spent TiO2/AC-3. Finally, it was found that this regeneration process could be greatly enhanced with the assistance of H2O2 and ultrasound by reducing the required regeneration time. 相似文献
53.
We investigated how information about family membership is coded by the individually specific anal gland secretion (AGS)
in the beaver, Castor canadensis. Because beavers live in strict family units and relatives share more features in the AGS profile than non-relatives, family
members share more AGS features than non-family members. Therefore, family recognition seems to be a natural consequence of
the more specific kin recognition. Multivariate statistical analyses revealed two possibilities in coding for family membership
using the multi-component AGS: either two (female) to three (male) AGS compounds or many compounds were used, but we were
not able to determine which possibility is more likely. Compounds were not equally important in coding family membership information,
and the interactions among compounds were complex. We attempted to reconstruct a lineage tree for the relationship among different
families using two–three or many compounds. We found there was no significant difference for trees constructed by using few
or many compounds in either males or females. However, the trees derived from male compounds and female compounds lacked good
congruence.
Received: 10 December 1998 / Accepted after revision: 13 July 1998 相似文献
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56.
通过分析建立闵行区环境数据中心的必要性,探讨闵行区环境数据中心的建设目标、原则和构建过程、意义、成果和不足,以期对闵行区环境数据进一步进行规范化管理。 相似文献
57.
A spot test for aqueous nitrate and nitrite for controlling nitrogen removal performance in small-scale wastewater treatment facilities is proposed. In this method, NO(2)(-) ion in water samples was allowed to react with sulfanilic acid and 1-naphthol to form an anionic azo dye. The resulting colored solution was introduced onto a mini column (similar to a gas detecting tube) packed with PVC particles coated with benzyl cetyl dimethyl ammonium chloride (BCDMA) and biphenyl. The NO(2)(-)-N concentration was determined visually by measuring the color band length (CBL) in the column. The CBL correlates linearly with nitrite concentration in the 4-20 mg-N l(-1) range. The concentration of nitrite+nitrate was determined after reduction to nitrite with zinc. The concentration of NO(3)(-)-N species was calculated by difference. This method was used to visually determine the concentrations of NO(2)(-)-N and (NO(2)(-)+NO(3)(-))-N in domestic wastewater samples with maximum suspended solid (SS) and chemical oxygen demand (COD) concentrations of 114 mg l(-1) and 73.9 mg l(-1), respectively. 相似文献