Synthesis of activated carbons from black sapote seeds,characterization and application in the elimination of heavy metals and textile dyes

Many different techniques may be used to remove industrial pollutants from wastewater. Adsorption using activated carbon has been reported to be an effective method. This work proposes the use of a vegetable residue(black sapote seeds) as a raw material for its synthesis. These carbons were chemically activated using phosphoric acid and carbonized at 673 and 873 K. Adsorption isotherms were constructed for the textile dyes on the carbons, and this data was treated using Langmuir’s equation to quantitatively describe the adsorption process. The synthesized carbons were characterized using FTIR, EA, SEM, Nitrogen adsorption(specific surface areas of 879 and 652 m2·g-1), and their points of zero charge(2.1 and 2.3). It was possible to adsorb both heavy metals and textile dyes present in aqueous solutions and wastewaters using these activated carbons. Heavy metals were adsorbed almost completely by both carbons. Cationic dyes where adsorbed(58–59.8 mg·g-1) in greater amounts compared to anionic dyes(10–58.8 mg·g-1). The amount of anionic dyes adsorbed increased almost 30% by changing the pH of the solutions. One of the carbons was thermally regenerated on three occasions without losing its adsorption capacity and it was proved in a flow system.

Epimorphisms between Finite 4-Valued Modal Algebras

In this paper, we determine conditions for the existence of an epimorphism between two finite 4-valued modal algebras and state a method to obtain it. Furthermore, we obtain formulas which generalize those indicated by R. Sikorski for finite Boolean algebras [1] 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003300380037003200340036003100310038000000 , and by M. Abad and A. V. Figallo for finite 3-valued ukasiewicz algebras [2] 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003300380037003200340036003100320031000000 .

Notes on the Variety of Ternary Algebras

In this work we review the class T of ternary algebras introduced by J. A. Brzozowski and C. J. Serger in [1]. We determine properties of the congruence lattice of a ternary algebra A. The most important result refers to the construction of the free ternary algebra on a poset. In particular, we describe the poset of the join irreducible elements of the free ternary algebra with two free generators.

Adjuvants Derived from <i>Neisseria meningitidis</i>Serogroup B Induce a Cross Reactive Response against <i>Neisseria gonorrhoeae</i>in Mice

Introduction: Neisseria is a large genus of bacteria that colonize mucosal surfaces. Of the 11 species that colonize humans, only two are pathogens, N. meningitidis and N. gonorrhoeae. Both are obligate human pathogens;the last is causal agent of gonorrhea disease. Although curable with timely antibiotic treatment, an annual incidence of more than 62 million cases is estimated by the World Health Organization and there are no successful vaccines available. In contrast, several prophylactic vaccine options for Neisseria meningitidis meningitis do exist. Of note, there is trace of cross parenteral response induced between N. meningitidis and N. gonorrhoeae, and Proteoliposome (PL, also named outer membrane vesicles, OMV) vaccine has shown high impact on this response. Objective: To determine effect of VAMENGOC-BC? and its derivates (AFPL1 and AFCo1) at mucosal and systemic level and possible cross response against Neisseria gonhorroeae in Balb/c and C57Bl/6 mice. Methods: We evaluated cross response against N. gonorrhoeae in mouse serum IgG and saliva IgA after mucosal immunization with VA-MENGOC-BC or its derivatives (AF, Adjuvant Finlay PL1 or AFCo (cochleate) 1). Results: Immunizations with AFPL1 or AFCo1 induce anti N. gonorrhoeae at saliva IgA and serum IgG responses similar to VA-MENGOC-BC? vaccine. Conclusions: Such data confirms a new possible window of prime-boost vaccination strategy against gonorrhea and extends our knowledge regarding the effect of PL vaccines on cross responses.

Estimation of the Foliar Area by Non-Destructive Methods in Two Stages of Growth of Pepper Plants(Capsicum annuum L.)Hybrid Salvador

The present work was aimed to obtain a model for the determination of the leaf area in function of the length and width of the leaves in pepper (Capsicum annuum L.) hybrid Salvador. The research was carried out in nursery conditions at the Experimental Campus La Teodomira, located in the parish of Lodana, Santa Ana, province of Manabí, Ecuador, in 2016, in the stages of initiation of flowering and flowering-fructification. In each phase 100 physiologically mature leaves of different sizes were collected. Leaves were digitalized in a rectangle with known dimensions, which allowed the area to be calculated through the percentage of pixels of different colors. From the determination of the length and maximum width of each leaf and the estimated area through the digitization process, the regression models were obtained, selecting the better fit generated between the leaf area and the product of the length by the maximum width of the leaf (). In the initiation of flowering stage the quadratic model generated the best coefficient of determination (R2 = 0.958), whereas in the flowering-fructification stage the best coefficient of determination was achieved by the cubic model (R2 = 0.955). The practical applicability of other simpler models among the tested ones, which show a high accuracy and sacrifice a low percentage of error, is discussed.

Deforestation and fragmentation trends of seasonal dry tropical forest in Ecuador: impact on conservation

Background:Fragmentation and deforestation are one of the greatest threats to forests,and these processes are of even more concern in the tropics,where the seasonal dry forest is possibly one of the most threatened ecosystems with the least remaining surface area.Methods:The deforestation and fragmentation patterns that had occurred in Ecuadorian seasonal dry forests between 1990 and 2018 were verified,while geographic information systems and land cover shapes provided by the Ecuadorian Ministry of the Environment were employed to classify and evaluate three types of seasonal dry forests:deciduous,semi-deciduous,and transition.The study area was tessellated into 10 km2 hexagons,in which six fragmentation parameters were measured:number of patches,mean patch size,median patch size,total edge,edge density and reticular fragmentation index(RFI).The RFI was also measured both outside and inside protected natural areas(unprotected,national protected areas and protected forest).Moreover,the areas with the best and worst conservation status,connectivity and risk of disappearance values were identified by means of a Getis-Ord Gi*statistical analysis.Results:The deforestation of seasonal dry forests affected 27.04%of the original surface area still remaining in 1990,with an annual deforestation rate of−1.12%between 1990 and 2018.The RFI has increased by 11.61%as a result of the fact that small fragments of forest have tended to disappear,while the large fragments have been fragmented into smaller ones.The semi-deciduous forest had the highest levels of fragmentation in 2018.The three categories of protection had significantly different levels of fragmentation,with lower RFI values in national protected areas and greater values in protected forests.Conclusions:The seasonal dry forest is fragmenting,deforesting and disappearing in some areas.An increased protection and conservation of the Ecuadorian seasonal dry forest is,therefore,necessary owing to the fact that not all protection measures have been effective.