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Integração energética de biorrefinarias de cana-de-açúcar com operação multiperiódica
(Universidade Federal de São Carlos, 2018-01-16) Oliveira, Cássia Maria de; Costa, Caliane Bastos Borba; https://lattes.cnpq.br/1602653870311562; Cruz, Antonio José Gonçalves da; https://lattes.cnpq.br/1812806190521028; https://lattes.cnpq.br/8332048666190385
Brazil has a great importance as biofuels producer, especially of ethanol from sugarcane. The bagasse, a byproduct of sugarcane biorefineries, can be used to generate electricity and produce second generation ethanol. However, variations in prices of electricity and ethanol may motivate variations in the operating conditions of the integrated biorefinery process, which produces first and second generation ethanol and bioelectricity. The heat exchanger network (HEN) of such a process must be able to meet these variations. This work aimed the synthesis of multiperiod HEN in sugarcane biorefineries. In this approach, each period indicates a process condition and the HEN synthesized is able to meet these different operating conditions. Three industrial case studies are considered. Case Study 1 (CS1) is a biorefinery that produces 1G/2G ethanol and electricity, disposing the pentoses fraction. In Case Studies 2 and 3, CS2 and CS3, the process is similar, but the pentoses fraction is used to produce ethanol (CS2) or biogas (CS3). For each biorefinery, three periods were considered, which differ in the bagasse fraction diverted to 2G ethanol production. In each period, a Mixed Integer Nonlinear Programming (MINLP) problem was solved to minimize the total annualized cost (TAC) and timesharing mechanisms were used to integrate the HENs of all periods into a multiperiod HEN. Optimization problems were solved at two levels using three different strategies. In the first strategy, an adapted Particle Swarm Optimization algorithm was used in both levels. However, the solutions by this method presented small TAC improvements compared to the process commonly found in Brazilian plants, where there is already energy integration among some process streams (called in this work of the process with project integration). To deal with this problem, two strategies were employed with hybrid metaheuristics: Simulated Annealing and Rocket Fireworks Optimization; and Tabu Search and Particle Swarm Optimization. For processes with the multiperiod HENs, these latter two strategies presented reductions above 58% and 54% in TAC and steam demand, respectively, compared to processes without energy integration. Also, using the aforementioned methods, improvements in TAC and steam demand for process with the multiperiod HENs reach values above 44% and 41%, respectively, in relation to processes with project integration. Such reductions in steam demand allow diverting more bagasse to produce second generation ethanol. In addition, energy integration in biorefineries provides improved energy management and reduced operating and capital costs. Thus, all these improvements contribute to 1G/2G ethanol and electricity production process.
Influência do sistema histaminérgico cerebelar no comportamento locomotor e ansiedade de camundongos
(Universidade Federal de São Carlos, 2018-01-16) Guilherme, Evelyn Maria; Gianlorenço, Anna Carolyna Lepesteur; https://lattes.cnpq.br/3861050459671690; https://lattes.cnpq.br/6269689282970701
The cerebellum is an important structure of the central nervous system with participation in motor and non-motor functions. The histaminergic system has a major role on the cerebellar neuronal circuit, but its function is not fully understood. The histamine can act through four types of receptors: H1, H2, H3 and H4. There are few studies about the role of the cerebellar histaminergic system on motor and non-motor functions. Thus, the main objective of this study is to investigate the effects of the intravermis cerebellar microinjections of histaminergic compounds, proposing a possible interaction of this system and the cerebellum on the modulation of motor and non-motor functions. The study was composed by five experiments, to evaluate the effects of Histamine (experiment 1), H1 receptor antagonist Chlorpheniramine (experiment 2), H2 receptor antagonist Ranitidine (experiment 3), H3 receptor antagonist Thioperamide (experiment 4) and H4 receptor agonist VUF-8430 (experiment 5) on the locomotor and anxiety-like behaviors in mice exposed to the open field test. A stereotaxic surgery was performed, and a guide canulla was implanted into the cerebellar vermis of mice weighing between 25 – 35g. Three days after surgery, the animals received the microinjection and were exposed to the open field behavioral test. The number of crossed quadrants, number of rearings and time in the central area was measured. The histological analysis confirmed the place of the microinjection. The statistical analysis was composed by one way ANOVA, follow by Duncan’s post hoc when appropriate. The results indicate that the higher doses of chlorpheniramine and VUF has an anxiogenic effect associated to increase of the locomotor and exploratory behaviors of mice, indicating a possible modulation of the cerebellar histaminergic system in these functions, through H1 and H4 receptors.