Over several centuries, the native vegetation of the flat part of the Bogotá Savanna has been almost completely replaced by crops, pastures and urbanization. The last remnant of this vegetation is a small forest (10 hm2), located at Hacienda Las Mercedes on the northern edge of the city of Bogotá. The reduced size and isolation of the forest, aggravated by the uncontrolled growth of invasive vegetation (lianas and wild blackberry) has resulted in the loss of many species. However, in recent years the forest has been subject to rehabilitation actions and currently the area is immersed in a reserve where more extensive restoration programs are planned. In order to evaluate changes in the bird community to estimate the effects of restoration actions, the avifauna present in 2001–2002 and in 2014 was recorded by visual and auditory records at fixed points in the forest. Twenty-seven forest species were found in the first census and 30 in the second, and the relative abundances of at least a third of them also increased over the 13 years, indicating a positive result in the recovery of the forest. The results highlight the recovery capacity of the degraded ecosystems and the importance of continuing with restoration actions in the reserve area.
In this paper, we introduce some certain fuzzy soft algebraic notions of generalized concepts in LA-Γ-semigroups and study some properties of their families.
Quartz sand was used as bed material in a small fluidized bed reactor with 1 kg/h feed. Corn straw powder with particle size of 20–40 mesh, 40–60 mesh, 60–80 mesh and 80–120 mesh was used as raw material for rapid pyrolysis at reaction temperatures of 400 °C, 450 °C, 500 °C and 550 °C. The bio-oil obtained after liquefaction of pyrolysis gas was analyzed. The variation trend of bio-oil composition in pyrolysis of corn straw powder with different reaction temperatures and raw material sizes was compared. The results show that: (1) the content of 3-hydroxyl-2-phenyl-2-acrylic acid in bio-oil increases with the decrease of raw material particle size, but it is less at 450 °C; (2) with the increase of reaction temperature, the content of hydroxyacetaldehyde in bio-oil increases at first and then decreases: the content of hydroxyacetaldehyde in bio-oil is the highest at 500 °C when the particle size is 20–40 mesh, and the highest at 450 °C with the other three particle sizes. Compared with other particle sizes, raw material with the particle size of 60–80 mesh is not conducive to the formation of aldehyde compounds; (3) the reaction temperature of 500 °C and the particle size of 60–80 mesh of raw materials are more conducive to the formation of phenolic compounds in bio-oil; (4) the ester compounds with particle size of 20–40 mesh in bio-oil is 20% higher than that of other particle sizes; (5) the reaction temperature and the particle size of raw materials had no significant effect on the formation of ketones, alcohols and alkane compounds in bio-oils.
Based on 898 English documents and 363 Chinese documents citing the Rising of Network Society, it studied that the knowledge contribution of citation content analysis and citation context analysis methods, and the knowledge contribution of Chinese and foreign quotations to human geography. The study found that “mobile space” is the most quoted theoretical view in domestic and foreign literature, and the proportion of domestic research is significantly higher than foreign research; the focus of domestic and foreign research focuses on the external spatial form and its transformation, while foreign research pays more attention on the internal spatial dynamics of network society and three types of knowledge contributions, reflecting the influence of “network social theory” on human geography. Among them, critical references reveal the shortcomings of “network social theory” point out the abstraction of “spatial duality” the importance of local space, and the limitations of research data, methods, and time background, which provides new enlightenment for the future application and innovation of “network social theory” in the field of human geography.
Metal organic framework is a class of hybrid network of supramolecular solid materials comprised of a large number of inorganic and organic linkers all bounded to metal ions in a well-organized fashion. This type of compounds possess a greater surface area with an advantage of changing pore sizes, diversified and beautiful structure which withdrew an intense interest in this field. In the present review articles, the structural aspects, classification, methods of synthesis, various factors affecting the synthesis and stability, properties and applications have been discussed. Recent advances in the field and new directions to explore the future scope and applications of MOFs have been incorporated in this article to provide current status of the field.
Studies related to the use of steel mill slag have become essential, because of the possibility of its use as a component of substrates in the production of seedlings and because this use minimizes the risk of environmental contamination, resulting from inadequate disposal. Thus, the objective of this work was to evaluate the effect of increasing levels of steel slag in substrates composed of soil with tanned bovine manure and sand, on the growth variables and the quality of “Dedo-de-moça” pepper (Capsicum baccatum L.) seedlings. A randomized block design was used with five slag concentrations (0%, 2.5%, 5%, 10% and 20%) and four repetitions. Evaluations occurred at 55 days after sowing, consisting of counting the number of leaves, measuring plant height and collar diameter, quantifying the dry mass of leaves and roots and determining the Dickson Quality Index. Regression models were fitted (P < 0.05) to treatments with increasing levels of steel slag. The addition around 10% of slag to the substrate provided the highest values of growth variables, in seedlings of Dedo-de-moça pepper.
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