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Optimization of chelating agents production process for agricultural administration of inorganic micronutrients
No full textIron Chelates: Production Processes and Reaction Evolution Analysis
No full textNowadays, fertilization using synthetic chelates is the most common technique to address iron chlorosis, a disease that affects plant growth. Ethylenediamine-N,N'-bis(o-hydroxyphenyl) acetic acid (EDDHA) is among the most efficient iron chelating agents. To produce EDDHA, a reaction was performed using as reactants phenol, ethylenediamine, glyoxylic acid, and sodium hydroxide. To study the reaction kinetics, samples were withdrawn from the reactor during the reaction and the kinetics was quantified, evaluating the yield evolution during the reaction phase. This study was useful to optimize the reaction time. Then, a catalyst was added to the reaction mixture to analyze its effect on the reaction evolution. Comparing the reaction evolution of the non-catalyzed and the catalyzed reaction protocols, two main results have to be highlighted: the time to reach the final yield is lower than the one proposed in the literature and the used catalyst has a minimum effect on the reaction rate
Optimization of Chelates Production Process for Agricultural Administration of Inorganic Micronutrients
Full text linkThe iron chlorosis is one of the most diffused plant disease, which affects their growth and reduces the yield of
harvests. This disease is caused by the iron deficiency and it is highlighted by the progressive yellowing of
plants due to the reduction of chlorophyll production. The most efficient and diffused therapy against the iron
chlorosis is the use of chelating agents and, among them, the o,o-EDDHA/Fe3+, the most stable isomer of
EDDHA, is the most used due to its capacity to guarantee a prolonged treatment.
The aim of this work is to develop a production process environment friendly, based on the recovering and
recycling of organic solvents to minimize the waste produced. The feed organic solvents ratio has been varied
evaluating the synthesis yield and the percentage of o,o-EDDHA/Fe3+ produced to identify the best feeding
conditions. Several products have been then tested on lettuce plants to determine their usability
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Hydrogel-Based Granular Phytostrengtheners for Prolonged Release: Production and Characterization
Full text linkSoil wellness is an indispensable requirement to obtain fruits and vegetables with finest quality and with high
yields. To the purpose, periodical administrations of nutrients, as well as phytostrengtheners could be
required. Crucial goals to maximize the economic and environmental sustainability of the whole cultivation are
the decrease of the dosages number together with the increase of the active substance availability within the
soil. With these aims a controlled release phytostrengtheners encapsulated in a granular Hydroxypropyl
methylcellulose matrix has been developed exploiting the wet granulation process. The granular product has
been analyzed in terms of Particle Size Distribution (PSD), morphology and flowability. The results showed the
effectiveness of the granulation process and the good flowability of the granules, highly desirable features for
the product handling and commercialization
Process innovation in the production of chelates for agricultural uses
Full text link2014 - 2015Analyzing the literature available on the production of iron chelates, it is clear as these extremely diffused products are produced according to processes developed in the second part of last century which involve the enormous use of organic solvents, chlorinated substances and water. Although these processes have been optimized, they are not environmentally sustainable and imply high costs of post processing operations and disposal of dangerous substances.
Based on this scenario, it is clear the necessity to develop a production process environmentally friendly, based on the elimination of chlorinated substances and the reduction of organic solvents use... [edited by Author]XIV n.s
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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