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31.
Environmental Science and Pollution Research - In recent years, research has been conducted in search of alternative adhesives that are less harmful to human health and the environment. Cardanol...  相似文献   
32.
This work aimed to evaluate the effect of sewage sludge application as fertilizer on the plasticity of functional characteristics of species commonly found in the Caatinga. The research was developed in the nursery of the Federal Institute of Education, Science and Technology of Ceará (IFCE), Quixadá campus, located in northeastern Brazil. Three treatments were applied: raw sludge, sanitized sludge, and no manipulation. In each treatment, five species were planted, each with five individuals, totaling 75 individuals, which were tagged, and 4 months after germination, they were destroyed to obtain dry matter content (TMSF) from leaf, stem (TMSC), fine root (TMSRF), and thick root (TMSRG); leaf area; height and diameter of the seedling; and length above and below the ground. The sanitized sludge was responsible for giving higher values for leaf area, height of the seedlings, and diameter and length of stem and root. However, the dry matter content of the fine roots was higher in the treatment without manipulation. At the community level, as TMSRG increased, TMSC also increased, the same occurred between TMSRG and TMSRF, TMSC and TMSRF, and stem length and leaf area. In the treatment without manipulation, there was a positive correlation between leaf area, height and plant diameter, and negative correlation between root length and plant diameter. Thus, it can be concluded that the use of sanitized sludge is a good tool to increase the availability of soil resources, conferring to individuals’ greater dry matter content, greater leaf area, and higher height and diameter above the ground.  相似文献   
33.

The identification of species-rich areas and their prognosticated turnover under climate change are crucial for the conservation of endemic taxa. This study aims to identify areas of reptile endemicity richness in a global biodiversity hot spot (Morocco) under current and future climatic conditions and to investigate the role of protected areas in biodiversity conservation under climate change. Species distribution models (SDM) were performed over the distribution of 21 endemic reptiles, combined to estimate current species richness at 1?×?1 km resolution and projected to years 2050 and 2080 according to distinct story lines and ensemble global circulation models, assuming unlimited and null dispersion ability. Generalized additive models were performed between species richness and geographic characteristics of 43 protected areas. SDM found precipitation as the most important factor related to current species distributions. Important reductions in future suitable areas were predicted for 50 % of species, and four species were identified as highly vulnerable to extinction. Drastic reductions in species-rich areas were predicted for the future, with considerable variability between years and dispersal scenarios. High turnover rates of species composition were predicted for eastern Morocco, whereas low values were forecasted for the Northern Atlantic coast and mountains. Species richness for current and future conditions was significantly related to the altitude and latitude of protected areas. Protected areas located in mountains and/or in the Northern Atlantic coast were identified as refugia, where population monitoring and conservation management is needed.

  相似文献   
34.
The most critical aspect of polymerization reactors is the agitator's stop and becomes more serious when this occurs exactly at the removal of the heat load, which is generated by the reaction (exothermic). This phenomenon is typical in power-failure situations of the energy supply or because of other related problems at the plant. The objective of this work is to compare the performance of two configurations for the inhibition-injection system for vinyl chloride monomer (VCM) polymerization reactors. To determine the injection time a rigorous mathematical model was developed. From the results of this work one of the configurations was implemented in an industrial plant.  相似文献   
35.
The northeastern Atlantic and the Mediterranean Sea share geological histories and display great faunal affinities. The majority of the Mediterranean species have Atlantic origins, with a few species with tropical affinities. These include the parrotfish Sparisoma cretense and the wrasse Thalassoma pavo that are restricted to the subtropical northeastern Atlantic, the Macaronesian archipelagos (Azores, Madeira, and Canaries) and the southern Mediterranean. The Pleistocene glaciations have been described as having different effects on the fauna of the two regions. During glacial peaks, Mediterranean waters remained warmer than those of the adjacent Atlantic. Within the eastern Atlantic, the effects of Pleistocene glaciations were differentiated. Here, we perform a comparative analysis focusing on T. pavo and S. cretense populations from the northeastern Atlantic and the Mediterranean to assess the effects of Pleistocene glaciations in these two species. Sequences from the mitochondrial control region were obtained and analyzed combining phylogeographic and demographic approaches. Gene flow between Atlantic and Mediterranean populations was shown to be very high. The Mediterranean populations of T. pavo and S. cretense showed high levels of genetic diversity, even in the eastern basin, pointing to an ancient colonization event. This suggests that both species must have been able to persist in the Mediterranean during the cold Pleistocene periods. Historical migration estimates revealed a Mediterranean towards Atlantic trend in the case of T. pavo, which may reflect the re-colonization of areas in the Atlantic by fish that survived the cold phases in relatively warmer Mediterranean refugia. Our data also showed that within the Macaronesian Archipelagos, migrations occurred from Madeira towards the Azores, for both T. pavo and S. cretense, thus supporting a post-glacial colonization of the Azores by fish that persisted in the warmer region of Madeira. Similar geographic distributions, thermal affinities, and means of dispersion for T. pavo and S. cretense resulted in a similar response to the effects of Pleistocene glaciations, as evidenced by identical phylogeographic patterns.  相似文献   
36.
Jackfruit starch based biodegradable films containing lysozyme were characterized for their antimicrobial activity, thickness, solubility, water vapor permeability and mechanical properties. The biodegradable films had good appearance and antimicrobial activity against Micrococcus lysodeikticus. The thickness of the biodegradable films were not affected by the variation in pH, but the addition of lysozyme increased the thickness, the thickest films being those with the highest lysozyme concentrations. The variation in pH of the filmogenic solutions affected the solubility of the biodegradable films, water solubility being greatest at pH 7.0 and with the highest lysozyme concentration. The permeability of the biodegradable films was increased by incorporating lysozyme. The lysozyme concentration and pH variation caused changes in the mechanical properties. The addition of 8% lysozyme increased the tensile strength and Young’s modulus for all the pH values studied. With respect to the release of antimicrobial activity, the diffusion of lysozyme was shown to follow Fickian transport mechanism.  相似文献   
37.
This study attempted to assess a bioclimate index and the occurrence of an urban heat island in the city of Campina Grande, northeastern Brazil, using data taken from mobile measurements and Automatic Weather Stations (AWS). The climate data were obtained during two representative months, one for the dry season (November 2005) and one for the rainy season (June 2006) at seven points in an urban area. Ten-minute air temperatures recorded by an AWS installed in urban areas were compared to those from a similar station located in a suburban area to assess the urban heat island (UHI). The data were collected using a 23X data logger (Campbell Scientific, Inc.) programmed for collecting data every second. The thermal discomfort level was analyzed by Thom’s discomfort index (DI), and an analysis of variance was applied for assessing if there was any statistically significant difference at the 1% and 5% significance level of thermal comfort among points. Mann–Kendall statistical test was used for identifying possibly significant trends in a time series for air temperature, relative humidity, and class A pan evaporation for the city of Campina Grande. The present study found UHI intensities of 1.48°C and ??0.7°C for the months taken as representative of the dry and rainy seasons, respectively. Summer in the city has partially comfortable conditions while the winter is fully comfortable. There are significant changes in DI hourly values between seasons. Only during the rainy season did all points of the city have a comfortable condition until 8:19 h, at which time they become partially comfortable for the rest of the day. Results indicated that there was a 1.5°C increase in air temperature and a 7.2% reduction in relative humidity throughout the analyzed time series. The DI also showed a statistically significant increasing trend (Mann–Kendall test, p?<?0.01) for the dry and rainy seasons and annual period of approximately 1°C in the last 41 years in the city of Campina Grande.  相似文献   
38.
Quantification of the accumulated or eroded sediment is an important procedure towards the understanding of shoreline migration and therefore, to the evaluation of littoral dynamics. Tróia Peninsula is a sand spit, made up of dunes and beaches. It is located on the left margin of the Sado River mouth near the foot of the Arrábida Mountain, on the west coast of Portugal, 30?km south of Lisbon. Data from 1928 to 1995 clearly shows an oceanwards coastline migration during this period. The objective of this work is to quantify the volume of sediment accumulated in the NW sector of Tróia Peninsula from 1928 to 1995, a 67?years period, and determine sediments net accumulation rate for that period of time. Using the 1928 bathymetry, from a 1930 nautical chart, and the altimetry, from the 1995 Imoareia topographic survey, the volume of sediments accumulated was calculated, with a Geographic Information System. Digital Terrain Models, representing the topography and bathymetry of both years, were created for the evaluation. Results show a positive variation of 5.718.224?m3 for an area of 938.440?m2, i.e. a net sedimentation rate of approximately 85.000 m3year-1 or 0,09 myear-1.  相似文献   
39.
A fragment of the mitochondrial control region was used to assess phylogeographic patterns and historical demography of the sand-smelt Atherina presbyter in the North-eastern Atlantic, covering its geographical range. A striking result is the highly marked differentiation between the Canary Islands population and western European ones. A genetic structure among European populations of A. presbyter was revealed, with a pattern of isolation-by-distance or a gradient effect at a scale of hundreds kilometres, an uncommon pattern likely related to the biological and life-history traits of the sand-smelt. The northern European populations present a much lower genetic diversity when compared to southern populations, which is consistent with a recent colonization from southern populations. The results showed signs of Pleistocene signatures, with the population age estimates for the European populations being clearly older than the Last Glacial Maximum (18,000 years bp). Nevertheless, paleotemperature reconstructions show that the sand-smelt could not have inhabited the western European shores during the last glacial phase. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
40.
Environmental Science and Pollution Research - Ciprofloxacin (Cipro) water contamination is a global concern, having reached disturbing concentrations and threatening the aquatic ecosystems. We...  相似文献   
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