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Mechanized sugarcane (Saccharum spp.) harvest without burning has been increasingly adopted in Brazil, increasing trash availability on the fi eld. This study aims at showing the importance of using an integrated framework tool to assess technical and economic impacts of integral harvesting and baling trash recovery strategies and different recovery rates as well as its implications in the sugarcane production, transport and processing stages. Trash recovery using baling system presents higher costs per unit of mass of recovered trash in comparison to system in which trash is harvested and transported with sugarcane stalks (integral harvesting system). However, the integrated agricultural and industrial assessment showed that recovering trash using baling system presents better economic results (higher internal rate of return and lower ethanol production cost) than the integral harvesting system for trash recovery rates higher than 30 %. Varying trash recovery fraction, stalks productivity and mean transport distance for both integral harvesting and baling systems, sensitivity analyses showed that higher trash recovery fractions associated with higher stalks yields and long transport distances favors baling system, mainly due to the reduction of bulk load density for integral harvesting system under those conditions.

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RESUMO A presente pesquisa trata do estudo de biodigestores de batelada mantidos a diferentes temperaturas, visando analisar os níveis mais favoráveis à produção de biogás e à degradação de sólidos totais e voláteis de esterco bovino. A temperatura mais adequada obtida em laboratório (31ºC) foi aplicada em um biodigestor rural modelo indiano, com 10m3 de capacidade, a fim de se verificar seu desempenho.

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Vinasse, a residual substance left after sugarcane alcohol distillation, represents a major environmental problem for the ethanol industry. No one has found a convenient and economical disposal solution for this black-reddish (Vinasse presents a light brown color and a low total solids content, from 2-4%, when it is obtained from straight sugarcane juice and a black-reddish color and total solids ranging from 5-10% when it is obtained from sugarcane molasses, which is the case of the vinasse used in this study.), viscous, high B.O.D. and acid material which is produced in quantities up to 15 times larger than those of the alcohol itself. This research investigated and developed the basic technology of on-site disposal of vinasse by combustion. Besides the clean ecological benefit, this method promotes energy savings and extra benefits when rich potassium vinasse ash is commercialized. Basic research was conducted using the facilities in the Combustion Laboratory (Mechanical Engineering Dept. at the Louisiana State University Campus in Baton Rouge). This research on vinasse combustion consisted of determining heating values, composition, and flame characteristics through combustion tests. Initially only vinasse was used in different solid concentrations and later emulsions were prepared using vinasse and # 6 fuel oi

We investigate the determination of a Hamiltonian parameter in a quantum system undergoing continuous measurement. We demonstrate a computationally rapid yet statistically optimal method to estimate an unknown and possibly time-dependent parameter, where we maximize the likelihood of the observed stochastic readout. By dealing directly with the raw measurement record rather than the quantum state trajectories, the estimation can be performed while the data is being acquired, permitting continuous tracking of the parameter during slow drifts in real time. Furthermore, we incorporate realistic nonidealities, such as decoherence processes and measurement inefficiency. As an example, we focus on estimating the value of the Rabi frequency of a continuously measured qubit, and compare maximum likelihood estimation to a simpler fast Fourier transform. Using this example, we discuss how the quality of the estimation depends on both the strength and duration of the measurement; we also discuss the trade-off between the accuracy of the estimate and the sensitivity to drift as the estimation duration is varied.

Mechanization in the sugarcane agriculture has increased over the last few years, especially in harvesting and planting operations, in the Brazilian Center-South region. The consequences of such a technological shift, however, are not fully comprehended when multiple perspectives are considered such as economic aspects, environmental regulations, and social context. The main goal of this study is to generate comprehensive information to subsidize decision-making processes not only in Brazil but also in other countries where sugarcane production is still under development. Manual and mechanical technologies for planting and harvesting were evaluated (with and without pre-harvest burning), as well as straw recovery, seeking to identify their advantages and disadvantages, considering economic, environmental, and social aspects. Considering vertically integrated production systems (agricultural and industrial phases), sugarcane production scenarios were compared under the metrics from engineering economics, life cycle assessment (LCA), and social LCA. Manual technologies were related to the highest job creation levels; however, lower internal rates of return and higher ethanol production costs were also observed. In general, mechanized scenarios were associated with lower ethanol production costs and higher internal rates of return due to lower biomass production cost, higher ethanol yield, and higher electricity surplus. Considering the restrictions for sugarcane burning and practical diffi culties of manual harvesting of green cane, environmental analysis showed that mechanical harvesting of green cane with straw recovery presents, in general, the best comparative balance of of the sustainability aspects. Th e aims were to analyze the economic, social, and environmental aspects of manualand mechanical-based sugarcane production systems in Brazil, as well as their eff ects on the ethanol production system when a vertically integrated production model is considered. Th is work identifi es strengths and weaknesses of these technologies and enlightens decision making processes in other countries with substantial potential for sugarcane production expansion for bioenergy, such as South Africa, Mozambique, Colombia, Guatemala, among others. Materials and methodsIn this paper, the Virtual Sugarcane Biorefi nery (VSB) was used to perform the simulations which give support to the technology assessments. Th e VSB has been developed by the Brazilian Bioethanol Science and Technology Laboratory (CTBE/CNPEM), which is an integrated computer simulation platform that evaluates technologies in use or under development, estimating the economic, environmental, and social impacts of the entire sugarcane production chain.22 Th e computational model for simulation and quantification of important parameters for technical, economic, environmental, and social assessment of the agricultural practices in the sugarcane production system are performed in CanaSoft . Th is model, which is one of the tools within VSB, is based on spre...