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A research report submitted to the School of Social Sciences, Faculty of Humanities of the University of the Witwatersrand in partial fulfilment of the requirements for the degree of Master of Arts in History 04 May 2015 / This report analyzes the reasons behind the adoption of out growing schemes (sistemas canavieiros) by two Mozambican sugar companies, namely the Companhia do Buzi and the Açucareira de Moçambique as well as the impacts of the companies’ decision on the mills as well as on local communities. Analyzing the adoption of out growing schemes is relevant due to the fact that the Companhia do Buzi and the Açucareira de Moçambique were the only two out of ten Mozambican sugar companies to collaborate with out growers. All the out growers were Portuguese citizens or ‘civilized’ Africans. The report also analyses the reasons and the impacts of the collapse of those schemes in the early post-colonial period. The report argues that the mills adopted out growing schemes to face the long term shortage and increasing costs of African agricultural labour. This strategy solved their problems but left the out growers indebted and frustrated and local communities dispossessed. On the collapse of the out growing schemes, the report argues that it resulted from the increasing lack of economic feasibility of sugar cane growing, which was a result of economic crisis and the authorities’ hostility towards the out growers.

O trabalho apresenta a fuligem proveniente de queima de bagaço de cana-de-açúcar como um adsorvente e como matéria-prima alternativa na produção de adsorvente descorante. Atualmente, todas as industrias açucareiras, várias refinarias de açúcar e algumas industrias utilizam o bagaço de cana-de-açúcar como combustível de caldeira. Originando, nessa queima, uma quantidade razoável de um resíduo sólido, que e a fuligem. Foi obtido em escala de laboratório, uma fuligem suportada em uma matriz inorgânica de diatomito, bentônica e acido fosfórico. O sólido obtido foi ativado termicamente. Adsorventes foram caracterizados por: rendimento, ph, massa especifica, composição química elementar, porosidade e teor de umidade, cinzas, solúveis, insolúveis, voláteis. Foi também realizada uma avaliação de desempenho do adsorvente, por batelada (dispersão) e por processo continuo (coluna). Os resultados mostram que e viável a obtenção de um adsorvente de fuligem. Sendo o mesmo, similar ao carvão de ossos, em trabalhos de descoloramento de caldas de açúcar. A fuligem também apresenta um excelente poder de adsorção para fenol. / The work presents the fly ash from sugar cane bagasse burning as na adsorbent and alternative material to the production of colour-materials adsorbent. Nowadays, all the sugar industries, many sugar refineries and some other industries use the sugar cane bagasse as a boiler fuel. From this burning an available amount of solid waste, called fly ash as produced. We obtained in laboratory scale, fly-ash supported in a diatomite, bentonite and phosphoric acid inorganic matrix. The solid obtained, was thermal activated. Adsorbents were characterized by: yield; pH; specific weight density; chemical elementar composition; porosity; humidity; ash; solubles; insoluble and volatiles content. It was also carried out on adsorbent performance evaluation by batch (dispersion) and continuous (column) processes. The results showed that it is possible to obtain a fly-ash adsorbent which works as similar as bone-chair, in discolouring sugar liquors. Fly-ash is also an excellent adsorbent for phenol.

Orientador: José Anchieta Gomes Neto / Banca: Massao Ionashiro / Banca: Fernando Gustavo Tonin / Banca: Marcia Andréia Mesquita Silva da Veiga / Banca: Ana Rita de Araújo Nogueira / Resumo: A influência da composição de diferentes fertilizantes foliares, designados por tertemunha (T1), fosfito(T2), micronutrientes(T3), fosfito+micronutrientes (T4), bioestimulantes(T5), fosfito+bioestimulante (T6), micronutrientes+bioestimulantne(T7), fosfito+micronutrientes+bioestimulante(T8), foi avaliada na nutrição e produtividade da cana-de açúcar da sfra de 2007/2008. Foram desenvolvidas novas metodologias analítica para determinações multielementares de Cu, Fe, MN e Zn em extrato de solo e Cu, Fe, Mn, Sn, Ca, K e Mg em folhas de cana-de-açúcar por espectrometria de absorção atômica em chama como rfo9nte contínua e de alta resolulção (HR-CS FAAs). A produtividade da caqna-de açucar foi avaliada por meio da análise do grau Brix, açucares totais recuperáveis (ATR), teor de sacarose, massa de colmos, e massa de colmos x ATR. As determinações de micronutrientes em solo foram feitas empregando as linhas atômicas principais de Cu (324,754nm), MN(279,482nm), Zn (213,857nm) e a secundária (252,744nm)e adjacente (248,325nm) do Fe. Exatidão e precisão foram avaliados pela análise de dois materiais de referência do Instituto Agronômico de Campipnas (IAC) e os... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The influence of the composition of differents foliar fertilizers referred by testify (T1), phosphite (T2), micronutrients (T3), phosphite + micronutrients (T4), biostimulant (T5), phosphite +biostimulant (T6), micronutrients+biostimulant (T7), phosphite +biostimulant +micronutrients (T8) was evaluated on nutrition and yield of 2007/2008 sugarcane crop. New analytical methodologies were developed for multielement determinations of Cu, Fe, Mn and Sn in soil extract and Cu, Fe, Mn, Sn, Ca, K and Mg in sugarcane leaves by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAs). The sdugarcane yield was evelluated by anaysis of Brix degree, total recoverabel sugars (TRS), sucros content and total stalk weight (TSW). The determination of micronutrients in soil were carried out using the main lines for Cu (324,754nm), MN(279,482nm), Zn (213,857nm) and the secondary (252,744nm) and adjacent (248,325nm) for Fe. Accuracy and precision were evalueted by analysis of two reference materials of the Agronomic Institute of Campinas (IAC) and the results were in agreement at a 95% confidence level. The... (Complete abstract click electronic access below) / Doutor

The research concerns the design and implementation of mechatronic systems to assist in the operation and control of a sugar cane harvester. Two functions were chosen for attention, the primary separation system, and the ‘topper’ that discards the leafy crown. Although these operations are given low priority by the operator of the harvester, their optimisation is of particular significance to the industry. Optimum separation requires a fine balance between discarding ‘trash’ that would contaminate the quality of the cane billets and losing good sugar-bearing material through over cleaning. Poor control of the topper can create extra load for the separation system and cause it to operate at a low efficiency with high loss. Alternatively it can cause a length of sugar-bearing cane stalk to be lost before it even enters the harvester system at all. A variety of mechatronic techniques were explored, that addressed the problem of providing useful data directly from the harvester functions and the electronic instrumentation to allow the data to be collected in a useful form in real-time. Computer control issues were also investigated, to make best use of the data stream. Novel acoustic transducers were introduced to the sensory separation system to provide a signal that indicated material striking the fan blades. A rotary transformer was required to allow transmission of the signal, and a signal interface system was implemented to record the returned data. Many real-time time-series analyses were conducted, and from these a suitable algorithm to extract an impact signal was developed. This system was assessed under harvesting conditions with results that confirmed its ability to quantify the amount of cane lost from the harvest. An investigation was conducted to detect the optimum topping height on a sugar cane stalk. The techniques considered both the internal and external attributes of the stalk, and a method was selected to measure the sugar concentration with a chemical sensor. An important design parameter was that the sensor must operate on the harvester in real time. The novel refractometer worked well in laboratory conditions, yielding repeatable and accurate results. The field environment complicated the application of this system, however this was partly overcome with introduction of a custom sample-crushing mechanism. This device provided the necessary juice sample from a selection of the topped cane stalks. The complete sampling and measuring mechanism operated well on cane stalks, and returned encouraging results. Both sets of data returned useful information regarding the operation of the particular harvester operations. The control of either the separation system or the topper requires careful balancing, and novel control techniques that consider the ergonomics for the operator are discussed. These include visual indication devices through to automatic control algorithms. With the integration of mechatronic techniques into the functioning of the sugar cane harvester, the overall efficiency of many of its functions may be improved, and the operator’s task may be greatly simplified. The ultimate objective is to maximise the yield with an improved level of harvested and separated cane.

Ratoon stunting disease (RSD) of sugarcane was first recognized in 1944 in Queensland, Australia (Steindl, 1961). The disease occurs worldwide and causes significant yield losses, especially during drought. RSD produces no external symptoms except a non-specific stunting (Steindl, 1961). RSD, which was first recorded 1n South Africa in 1953 (Anon., 1960), causes a greater overall loss in yield than any other sugarcane disease in South Africa. Yields of sugarcane are reduced by 20% to 40% and the harvest of affected fields declines progressively with successive ratoons (Anon., 1980b). A virus was originally thought to cause RSD, but in 1973, a coryneform bacterium was implicated as the causal agent (Gillaspie et al., 1973; Teakle et al., 1973). In 1980, our laboratory reported the successful isolation and culture of a coryneform bacterium associated with RSD of sugarcane and was indicated to be the causal agent (Nayiager et al., 1980). The lack of a rapid diagnostic technique applicable to mass screening of sugarcane has hindered progress in the control of the disease. There are two types of commonly used diagnostic tests. One test depends on the evaluation of internal stalk symptoms which may require from two to twenty six weeks to develop (Gillaspie et al., 1966; Matsuoka, 1971; Schexnayder, 1960; Singh, 1969). However, these symptoms are not always present in RSD affected plants and similar symptoms can sometimes result from other causes (Steindl, 1961). The other test involves establishing the presence of the coryneform bacterium associated with diseased plants. The bacterium is visible under high magnification by phase-contrast microscopy (Gillaspie et al., 1973) or by electron microscopy (Teakle et al., 1973). Although identification by the latter methods requires little time, the technology involved severely limits the number of samples that can be examined. Recently, serological techniques have been used (Brlansky et al., 1982; Damann et al., 1977; Davis et al., 1980; Gillaspie, 1978b; Gillaspie et al., 1979; Harris and Gillaspie, 1978) but their success has been limited. Besides problems with diagnosis of the disease, the precise morphology and taxonomy of the causal organism is unclarified. The objectives of this research programme were, firstly, to characterize the cultured intact bacterium and its constituent membranes both ultrastructurally and immunologically, and secondly, to evaluate various immunological methods for detection of the bacterium. This study should contribute to enhancing the taxonomic status of the bacterium and to the use of a rapid diagnostic technique applicable to mass screening of sugarcane. Such a technique should eventually contribute to effective control of RSD. / Thesis (M.Sc.)-University of Durban-Westville, 1984.

In the Australian sugar industry, sugar cane is smashed into a straw like material by hammers before being squeezed between large rollers to extract the sugar juice. The straw like material is initially called prepared cane and then bagasse as it passes through successive roller milling units. The sugar cane materials are highly compressible, have high moisture content, are fibrous, and they resemble some peat soils in both appearance and mechanical behaviour. A promising avenue to improve the performance of milling units for increased throughput and juice extraction, and to reduce costs is by modelling of the crushing process. To achieve this, it is believed necessary that milling models should be able to reproduce measured bagasse behaviour. This investigation sought to measure the mechanical (compression, shear, and volume) behaviour of prepared cane and bagasse, to identify limitations in currently used material models, and to progress towards a material model that can predict bagasse behaviour adequately. Tests were carried out using a modified direct shear test equipment and procedure at most of the large range of pressures occurring in the crushing process. The investigation included an assessment of the performance of the direct shear test for measuring bagasse behaviour. The assessment was carried out using finite element modelling. It was shown that prepared cane and bagasse exhibited critical state behaviour similar to that of soils and the magnitudes of material parameters were determined. The measurements were used to identify desirable features for a bagasse material model. It was shown that currently used material models had major limitations for reproducing bagasse behaviour. A model from the soil mechanics literature was modified and shown to achieve improved reproduction while using magnitudes of material parameters that better reflected the measured values. Finally, a typical three roller mill pressure feeder configuration was modelled. The predictions and limitations were assessed by comparison to measured data from a sugar factory.

Made available in DSpace on 2014-06-11T19:30:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-04-11Bitstream added on 2014-06-13T20:20:57Z : No. of bitstreams: 1 000757743.pdf: 4041576 bytes, checksum: 0f25cac829cd57c145c0ed6b1075b9ca (MD5) / Em Louisiana, historicamente, o resíduo de cana-de-açúcar obtido com a colheita mecânica tem sido removido pela queimada, mas preocupações ambientais e sociais sobre a queima têm conduzido à necessidade de alternativas econômicas para o manejo dessas palhada. O manejo de plantas daninhas nessas áreas apresenta mudanças significativas, visto que uma espessa camada de palha variando de 10 a 30 t ha-1 pode ser deixada no solo. Os herbicidas aplicados em pré-emergência, que deveriam chegar até a superfície do solo são interceptados pela palhada ficando o produto retido mais exposto às possíveis perdas. Dessa forma, o objetivo desse estudo foi avaliar a interação entre diferentes quantidades de palha de cana-de-açúcar e herbicidas, no controle de azevém (Lolium multiflorum) em Louisiana/USA, bem como verificar a transposição dos herbicidas atrazine, pendimethalin, metribuzin, clomazone, diuron e hexazinone em palha. O estudo foi conduzido em dois experimentos. O primeiro foi realizado na estação experimental de cana-de-açúcar da Louisiana State University, localizada em Saint Gabriel/Louisiana, nos Estados Unidos no período de novembro de 2012 a abril de 2013, em que se estudou o efeito dos herbicidas atrazine, pendimethalin, metribuzin, clomazone+diuron e hexazinone+diuron em condições de 0, 9, 18 e 27 t ha-1 de 2 palha de cana-de-açúcar deixada no solo. O segundo experimento foi desenvolvido nas condições do Núcleo de Pesquisas Avançadas em Matologia pertencente à UNESP Campus de Botucatu/SP, como um complemento ao experimento anterior, e o foco do estudo foi à transposição dos mesmos herbicidas em 10 t ha-1 de palha de cana-de-açúcar. Verificou se que a infestação de azevém foi gradativamente reduzida com o aumento na quantidade de palha de cana-de-açúcar deixadas na superfície do solo e os melhores tratamentos herbicidas foram metribuzin, clomazone+diuron... / In Louisiana, historically, the sugarcane residue obtained with mechanical harvesting has been removed by burning, but environmental and social concerns about burning have led to the need for economic alternatives for the management of these straw. The weed management in these areas presents significant changes, considering that a thick layer of straw from 10 to 30 t ha-1 can be left on the ground. And the herbicides applied in pre-emergence on these mulches, which should reach the soil surface are intercepted by straw getting the product more exposed to possible losses like photo degradation, volatilization and/or hydrolysis, thus not reaching the ground. So, the aim of this study was to evaluate the interaction between different amounts of sugarcane straw and herbicide to control of Italian ryegrass (Lolium multiflorum) in Louisiana/USA, as well as verify the transposition of the herbicides atrazine, pendimethalin, metribuzin, clomazone, diuron and hexazinone in straw. The study was conducted in two experiments. The first was conducted at the sugarcane experimental station of the Louisiana State University located in Saint Gabriel from November 2012 to April 2013 and the effect of atrazine, pendimethalin, metribuzin, clomazone+diuron, hexazinone+diuron were evaluated in conditions of 0, 9, 18 and 27 t ha-1 of sugarcane straw left in the soil. The second experiment was conducted under the conditions of the Advanced Research Center ...

Made available in DSpace on 2014-06-11T19:35:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-15Bitstream added on 2014-06-13T20:46:00Z : No. of bitstreams: 1 raposojunior_jl_dr_araiq.pdf: 6346951 bytes, checksum: 2a6134d61540835a78b50ad54ba2356f (MD5) / A influência da composição de diferentes fertilizantes foliares, designados por tertemunha (T1), fosfito(T2), micronutrientes(T3), fosfito+micronutrientes (T4), bioestimulantes(T5), fosfito+bioestimulante (T6), micronutrientes+bioestimulantne(T7), fosfito+micronutrientes+bioestimulante(T8), foi avaliada na nutrição e produtividade da cana-de açúcar da sfra de 2007/2008. Foram desenvolvidas novas metodologias analítica para determinações multielementares de Cu, Fe, MN e Zn em extrato de solo e Cu, Fe, Mn, Sn, Ca, K e Mg em folhas de cana-de-açúcar por espectrometria de absorção atômica em chama como rfo9nte contínua e de alta resolulção (HR-CS FAAs). A produtividade da caqna-de açucar foi avaliada por meio da análise do grau Brix, açucares totais recuperáveis (ATR), teor de sacarose, massa de colmos, e massa de colmos x ATR. As determinações de micronutrientes em solo foram feitas empregando as linhas atômicas principais de Cu (324,754nm), MN(279,482nm), Zn (213,857nm) e a secundária (252,744nm)e adjacente (248,325nm) do Fe. Exatidão e precisão foram avaliados pela análise de dois materiais de referência do Instituto Agronômico de Campipnas (IAC) e os... / The influence of the composition of differents foliar fertilizers referred by testify (T1), phosphite (T2), micronutrients (T3), phosphite + micronutrients (T4), biostimulant (T5), phosphite +biostimulant (T6), micronutrients+biostimulant (T7), phosphite +biostimulant +micronutrients (T8) was evaluated on nutrition and yield of 2007/2008 sugarcane crop. New analytical methodologies were developed for multielement determinations of Cu, Fe, Mn and Sn in soil extract and Cu, Fe, Mn, Sn, Ca, K and Mg in sugarcane leaves by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAs). The sdugarcane yield was evelluated by anaysis of Brix degree, total recoverabel sugars (TRS), sucros content and total stalk weight (TSW). The determination of micronutrients in soil were carried out using the main lines for Cu (324,754nm), MN(279,482nm), Zn (213,857nm) and the secondary (252,744nm) and adjacent (248,325nm) for Fe. Accuracy and precision were evalueted by analysis of two reference materials of the Agronomic Institute of Campinas (IAC) and the results were in agreement at a 95% confidence level. The... (Complete abstract click electronic access below)