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141.
Journal of Material Cycles and Waste Management - The relationship between local structure and visible-light-activated photocatalytic ability of glass–ceramics prepared from Municipal Solid...  相似文献   
142.
Environmental Science and Pollution Research - With the rapid growth of population, development of different industries, and production of several ranges of products, the generation of municipal...  相似文献   
143.
Environmental Science and Pollution Research - The objective of this study was to evaluate the effect of salinity on the acute and sub-chronic toxicity of silver nanoparticles (AgNPs) in Persian...  相似文献   
144.
Journal of Material Cycles and Waste Management - The bioleaching process comprises two mechanisms: direct action of the bacteria and indirect effect of low pH. In this work, the effect of bacteria...  相似文献   
145.
Environmental Science and Pollution Research - Nano-titania (n-TiO2), due to its unique photocatalytic and hydrophobic properties, can be used to prepare self-cleaning cement-based smart building...  相似文献   
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148.
Davidova  R.  Vasilev  V.  Boycheva  M.  Bakalova  J.  Ali  N. 《Russian Journal of Ecology》2019,50(2):200-207

The dynamics of nest-dwelling mites from the nests of the great tit in the protected area of Kamchia Mountain in Northeastern Bulgaria was investigated. The mite fauna inhabiting the nests of great tit differs significantly in terms of the degree of infestation, species richness, abundance and structure of communities in study years. There are statistically significant differences in the specimens’ number between 2014 and the other years 2012, 2013 and 2015. The mite species such as Dermanyssus gallinae, Androlaelaps casalis and Ornithonyssus sylviarum demonstrated significant changes in the abundance over the study years. A relation between the abundance of a species and the species diversity in the nests was not registered. Comparison of the annual dynamics of mites in the nests of great tit and the nests of semi-collared flycatcher for the same period of time and for the same environment, showed similarities—a significant fluctuation in the abundance of mites over the years and differences—in the species richness. Regarding the structure of the communities, both similarities and differences were recorded.

  相似文献   
149.
This paper reports on the firstPhaeocystis sp. (hereafterPhaeocystis) bloom in the Arabian Gulf. Total lipids from threePhaeocystis colonies sampled in November 1987 and in March and May 1988, comprised ca 11.0% of the dry biomass. Triacylglycerols (TG) and/or free fatty acids (FA) predominated in the lipids of all three samples. Polar lipids consisted of mixtures of phospholipids and glycolipids. Diacylglycerotrimethylhomoserines (DGTH) were present in all extracts, whilst conventional phospholipids only occurred in low concentrations. The predominant glycolipids were monogalactosyldiacylglycerols (MGDG) digalactosyldiacylglycerols (DGDG), sulfoquinovosyldiacylglycerols (SQDG) and steryl glycosides (SG). The predominant fatty acids in the total lipids of all three samples were palmitic (16:0) and oleic (18:1) acids. Total lipids of the November sample contained the smallest proportion of palmitic and the largest of polyunsaturated fatty acids (PUFA) — especially C16. The proportion of PUFA was considerable in individual polar lipids. C16 PUFA were more common in individual polar lipid classes of the November and March samples than that of May. The concentration of constituent C18 PUFA was relatively low. PUFA with chains longer than 18 C atoms only occurred in very low concentrations, and were confined to certain polar and nonpolar lipid classes of the November sample only.  相似文献   
150.
The native vascular plant flora of the Republic of Singapore has suffered the extinction of 594 out of a total 2277 species. These represent local, not global, species extinctions. Coastal habitats, including mangroves, have lost 39% of their species, while inland forests have last 29%. Epiphytic species (62% loss) appear particularly prone to extinction, which is reflected in a similar disposition exhibited by the Orchidaceae. Deforestation and disturbance have been the main cause of plant species extinction in Singapore. The rich mangrove epiphyte flora has been totally exterminated, and a number of tree species are reduced to populations of a few mature individuals. Many more species continue to survive than the species-area relationship would predict given the 99.8% loss of primary forest. This is interpreted as a result of the failure of equilibrium to be achieved yet in the remnant forest fragments, even after more than a century of isolation. Singapore's secondary forests appear to accrete plant diversity very slowly, even if contiguous with primary forest areas. We conclude that remnant fragments of primary tropical forest, even of very small size, can play a major role in the conservation of tropical biodiversity. The patterns of extinction observed in Singapore indicate that coastal and estuarine sites are in greatest demand for development and therefore must be given high priority for conservation despite their somewhat lower biodiversity. Epiphyte and orchid diversity appear to be very good indicators of the degree of disturbance suffered by a habitat in the humid tropics.  相似文献   
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