CHARACTERIZATION OF EQUILIBRIUM CONDITIONS OF ADSORBED SILICAGEL/WATER BED ACCORDING TO DUBININASTAKHOV AND FREUNDLICH

Systems of adsorption have been studied as an alternative for the cooling systems for saving electrical energy. The main advantage is the heat as the driving sources, for example, hot water or waste heat, widely used in the industries, and solar energy. The pair adsorbent/ adsorbate determines the behavior of these systems. Therefore, the knowledge of the equilibrium conditions between the adsorbent and the adsorbate is very important. The pair silica gel/water has the advantage of exploiting low-temperature heat sources. In this paper, the equilibrium conditions of the pair silica gel/water were investigated and the data were used to identify the coefficients of Dubinin-Astakhov equation and Freundlich equation. The experiments consisted of measuring temperature and pressure for different adsorbed mass of water in the adsorbent (silica gel). The amount of adsorbed mass (kg) per adsorbent mass (kg) used were: 0.007, 0.013, 0.024, 0.047, 0.092, 0.162 and 0.209. Both equations showed good agreement with experimental data, the coefficients of regression (R2) were 0.991 on the Dubinin-Astakhov equation and 0.993 for the Freundlich equation

Economic and risk factors of a transhipment system using electric cargo bikes for urban courier services

The distribution of goods in urban areas is a major challenge for managers in the public and private sectors, due to population growth, high density in large urban centers and, in many cases, lack of planning in urban cargo transport systems. In this context, the objective of this paper is to propose a novel collaborative urban cargo distribution system for logistics service providers, based on a transshipment terminal and usage of electric cargo bikes, highlighting the main aspects to consider on estimating its beneficial economic and environmental impacts in terms of emissions and the risk factors of the investment. The evaluation of this solution may be based on applying simple vehicle routing heuristics for assessing the distance travelled, costs and emissions. Also, a more sophisticated cost model is proposed to estimate the economic viability and risks associated to the use of electric cargo bikes. Finally, risk aspects can be evaluated through a structured methodology including both qualitative and quantitative approaches.This work has been supported by FCT -Fundacao para a Ciencia e Tecnologia (Portugal) within the Project Scope: UID/CEC/00319/2019

First-order decay models to describe soil C-CO2 Loss after rotary tillage

Para entendimento do impacto do preparo do solo sobre as emissões de CO2 desenvolvemos e aplicamos dois modelos conceituais que são capazes de prever a emissão de CO2 do solo após seu preparo em função da emissão da parcela sem distúrbio, acrescida de uma correção devido ao preparo. Os modelos assumem que o carbono presente na matéria orgânica lábil segue uma cinética de decaimento de primeira ordem, dada pela seguinte equação: dCsoil (t) / dt = -k Csoil (t), e que a emissão de C-CO2 é proporcional a taxa de decaimento do C no solo, onde Csolo(t) é a quantidade de carbono lábil disponível no tempo (t) e k é a constante de decaimento (tempo-1). Duas suposições foram testadas para determinação das emissões após o preparo do solo (Fp): a constante de decaimento do carbono lábil do solo (k) antes e após o preparo é igual (Modelo 1) ou desigual (Modelo 2). Conseqüentemente, a relação entre os fluxos de C das parcelas sem distúrbio (F SD) e onde o preparo do solo foi conduzido (F P) são dadas por: F P = F SD + a1 e-a2t (modelo 1) e F P = a3 F SD e-a4t (modelo 2), onde t é o tempo após o preparo. Fluxos de CO2 previstos e observados relevam um bom ajuste dos resultados com coeficiente de determinação (R²) tão alto quanto 0,91. O modelo 2 produz um ajuste ligeiramente superior quando comparado com o outro modelo. A velocidade das pás da enxada rotativa foi relacionada a um aumento na quantidade de carbono lábil e nas modificações do tempo de residência médio do carbono lábil do solo após preparo. A vantagem desta metodologia é que a variabilidade temporal das emissões induzidas pelo preparo do solo pode ser descrita a partir de uma função analítica simples, que inclui a emissão da parcela sem distúrbio e um termo exponencial modulado por parâmetros dependentes do preparo e de condições ambientais onde o experimento foi conduzido.To further understand the impact of tillage on CO2 emission, the applicability of two conceptual models was tested, which describe the CO2 emission after tillage as a function of the non-tilled emission plus a correction due to the tillage disturbance. Models assume that C in readily decomposable organic matter follows a first-order reaction kinetics equation as: dCsoil (t) / dt = -k Csoil (t), and that soil C-CO2 emission is proportional to the C decay rate in soil, where Csoil(t) is the available labile soil C (g m-2) at any time (t) and k is the decay constant (time-1). Two possible assumptions were tested to determine the tilled (F T) fluxes: the decay constants (k) of labile soil C before and after tillage are different (Model 1) or not (Model 2). Accordingly, C flux relationships between non-tilled (F NT) and tilled (F T) conditions are given by: F T = F NT + a1 e-a2t (model 1) and F T = a3 F NT e-a4t (model 2), where t is time after tillage. Predicted and observed CO2 fluxes presented good agreement based on the coefficient of determination (R² = 0.91). Model comparison revealed a slightly improved statistical fit of model 2, where all C pools are assigned with the same k constant. Rotary speed was related to increases in the amount of labile C available and to changes of the mean resident labile C pool available after tillage. This approach allows describing the temporal variability of tillage-induced emissions by a simple analytical function, including non-tilled emission plus an exponential term modulated by tillage and environmentally dependent parameters

State and new investment financing arrangements: alternatives for Brazil

sem informaçãoA lógica do pensamento keynesiano mostra como a incerteza envolvida na imobilização de capital restringe a dinâmica da economia e a necessidade de promoção de instituições que reduzam as condições de risco. A economia brasileira tem se defrontado, há déca261189213sem informaçãosem informaçãosem informaçã

Evaluation of band gap energy of TiO2 precipitated from titanium sulphate

The determination of the band gap energy () of semiconductors powder materials can be performed from diffuse reflectance spectroscopy (DRS) measurements. For this purpose, the classical theory proposed by Kubelka and Munk (K-M) and the so-called plot Tauc, both discussed here, have been largely employed. We investigate the values of anatase TiO2 particles synthesized by precipitation of titanyl sulphate in the presence of 5% ammonia solution and titanium and iron salts. Based on K-M function and Tauc plot and considering that the TiO2 anatase phase is an indirect band gap semiconductor, our results indicate that the samples subjected to a mechanochemical treatment (mill rotation speed equal to 300 rpm) present substantially lower values compared to those reported by other authors in a recent work(undefined

Tratamento conservador da retite actínica hemorrágica: uma revisão

Chronic radiation proctitis represents a challenging condition seen with increased frequency due to the common use of radiation for treatment of pelvic cancer. Hemorrhagic radiation proctitis represents the most feared complication of chronic radiation proctitis. There is no consensus for the management of this condition despite the great number of clinical approaches and techniques that have been employed. Rectal resection represents an available option although associated with high morbidity and risk of permanent colostomy. The effectiveness of nonoperative approaches remains far from desirable, and hemorrhagic recurrence represents a major drawback that leads to a need for consecutive therapeutic sessions and combination of techniques. We conducted a critical review of published reports regarding conservative management of hemorrhagic chronic radiation proctitis. Although prospective randomized trials about hemorrhagic radiation proctitis are still lacking, there is enough evidence to conclude that topical formalin therapy and an endoscopic approach delivering an argon plasma coagulation represent available options associated with elevated effectiveness for interruption of rectal bleeding in patients with chronic radiation proctitis.A retite actínica crônica é uma condição cada vez mais freqüentemente observada como resultado do crescente emprego da radioterapia no tratamento do câncer de órgãos pélvicos. A manifestação hemorrágica da retite actínica é a complicação mais comum dessa doença e seu tratamento é desafiador. Diversas técnicas foram empregadas para o tratamento dessa condição e não há evidência satisfatória acerca da melhor forma de controlar os episódios de sangramento de forma eficaz e duradoura. A necessidade de se realizar múltiplas sessões de tratamento conservador bem como a associação de técnicas freqüentemente observada no manejo desses pacientes dificulta a interpretação dos resultados. O objetivo dessa revisão foi avaliar a segurança e a eficácia das alternativas clínicas mais freqüentemente empregadas no controle da retite actínica hemorrágica. Ainda que a falta de estudos prospectivos e randomizados comparando duas ou mais alternativas terapêuticas impeça uma conclusão mais definitiva, concluímos que existe suficiente evidência acerca de elevada eficácia e segurança associadas ao emprego da formalina tópica e da coagulação por plasma de argônio no controle do sangramento em pacientes com retite actínica crônica

Applied optics in the development of smart asphalt mixtures

The functionalization of asphalt mixtures is carried out in order to provide new capabilities to the road pavements, with major social, environmental and financial benefits. Optical characterization techniques as well as optical processes like photocatalysis play a major role in the development of new asphalt mixtures with smart functions. These advanced capabilities which are being developed in asphalt mixtures are: photocatalytic, superhydrophobic, self-cleaning, de-icing/anti-ice, self-healing, thermochromic, and latent heat thermal energy storage. The main objective of this research work is to stress the importance of optics and photonics technologies giving an overview of advanced functionalized smart asphalt mixtures.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UIDB/04650/2020. This work was partially financed by FCT - Fundação para a Ciência e a Tecnologia - under the projects of the Strategic Funding UIDB/04650/2020, MicroCoolPav project EXPL/EQU-EQU/1110/2021, and NanoAir project PTDC/FISMAC/6606/2020

Dermatomyositis and Breast Calcinosis

The authors report a rare case of dermatomyositis diagnosed at the Mastology Sector of the Division of Gynecology of the Federal University of São Paulo - Escola Paulista de Medicina, which caused breast deformity due to formation of bilateral dystrophic calcifications.Os autores relatam caso raro de dermatomiosite diagnosticado no Setor de Mastologia da Disciplina de Ginecologia da Universidade Federal de São Paulo (UNIFESP) - Escola Paulista de Medicina, causando deformidade mamária devido à formação de calcificações distróficas bilateralmente.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Setor de MastologiaUNIFESP, EPM, Setor de MastologiaSciEL