994 resultados para External Carbon


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Sugarcane spirit is a drink considered as a national symbol of Brazil. It is produced by large producers and by about 30 thousand small and medium home-distilling producers dispersed throughout the country. The copper originating from the home-distillers can become a serious problem since at high concentrations in beverages it may cause serious human health problems. Therefore, the objective of this study was to investigate the influence of the activated carbon used in commercial filters on the physicochemical and sensory characteristics of aged sugarcane spirit. Analyses of copper, dry extract, alcoholic degree, higher alcohols, volatile acids, aldehydes, esters, furfural, and methanol were performed. The sensory evaluation was performed by seven selected trained judges, who analyzed the yellow color, woody aroma and flavor, and intensity of alcoholic aroma and flavor of the cane spirit before and after the filtration process. The sensory tests were carried out using a 9 cm non-structured intensity scale. A reduction was observed in all compounds analyzed physicochemically, except for the esters, which increased after filtration. This increase is probably due to the esterification of the alcohols and acids present. According to the sensory results obtained, a reduction was observed in the intensity of the yellow color, aroma, and wood flavor characteristics, the major characteristics of the aging process.

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Microbial pectinolytic enzymes are known to play a commercially important role in a number of industrial processes. Two kinds of yeast can be discerned regarding the production of enzymes. One group includes those which can produce enzymes in the absence of an inducer, and the other group comprises the yeasts that produce enzymes in the presence of an inducer. The objective of this study was to investigate the influence of pectic substances, glucose, pH, and temperature on the polygalacturonase activity by Kluyveromyces marxianus CCMB 322. The yeast was grown in a fermentation broth containing different concentrations of glucose and pectic substances. The polygalacturonase activity was determined by the DNS method, and the pH and temperature were optimized using a central composite experimental design. The polygalacturonase secreted by K. marxianus CCMB 322 was partially constitutive showing optimum pH and temperature of 7.36 and 70 °C, respectively, and maintained approximately 93% of its original activity for 50 minutes at 50 °C. Thermal stability of the polygalacturonase enzyme was studied at different temperatures (50, 60, 70, and 80 °C) and different incubation times (0, 10, 20, 30, 40, and 50 minutes). This study showed that glucose can influence the regulation of the synthesis of polygalacturonase.

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The aims of this study were to use the isotope analysis method to quantify the carbon of C3 photosynthetic cycle in commercial apple nectars and to determine the legal limit to identify the beverages that do not conform to the safety standards established by the Brazilian Ministry of Agriculture, Livestock and Food Supply. These beverages (apple nectars) were produced in the laboratory according to the Brazilian legislation. Adulterated nectars were also produced with an amount of pulp juice below the permitted threshold limit value. The δ13C values of the apple nectars and their fractions (pulp and purified sugar) were measured to quantify the C3 source percentage. In order to demonstrate the existence of adulteration, the values found were compared to the limit values established by the Brazilian Law. All commercial apple nectars analyzed were within the legal limits, which enabled to identify the nectars that were in conformity with the Brazilian Law. The isotopic methodology developed proved efficient to quantify the carbon of C3 origin in commercial apple nectars.

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The objective of this study was to evaluate the hygienic-sanitary conditions of hospital nutrition and dietary services using external and internal auditors. Eleven hospitals were evaluated for their nutrition and dietary services using an evaluation checklist based on food safety requirements in the current legislation. The checklist was applied by an internal auditor (a technical supervisor) and an external auditor (a professional with experience in food services) between August and October 2011. According to the number of items on the evaluation checklist that were considered adequate, the hospital facilities were ranked as excellent, good, regular, bad, or very bad. The results obtained by the auditors were compared. According to these results, it can be said that most of the hospital nutrition and dietary services were rated as good for overall quality by the internal auditor, while the external auditor classified them as Regular. There was a clear difference between the evaluations of the auditors, both in terms of the number of items considered adequate and the overall requirements' average score. It can be concluded that hospital nutrition and dietary services should meet safety requirements in order to provide food. These facilities should have external audits conducted as a way to prevent routine problems from being perpetuated.

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The aim of this thesis research work focused on the carbonate precipitation of magnesium using magnesium hydroxide Mg(OH)2 and carbon dioxide (CO2) gas at ambient temperature and pressure. The rate of dissolution of Mg(OH)2 and precipitation kinetics were investigated under different operating conditions. The conductivity and pH of the solution were inline monitored by a Consort meter and the solid samples gotten from the precipitation reaction were analysed by a laser diffraction analyzer Malvern Mastersizer to obtain particle size distributions (PSD) of crystal samples. Also the Mg2+ concentration profiles were determined from the liquid phase of the precipitate by ion chromatography (IC) analysis. Crystal morphology of the obtained precipitates were also investigated and discussed in this work. For the carbonation reaction of magnesium hydroxide in the present work, it was found that magnesium carbonate trihydrate (nesquehonite) was the main product and its formation occurred at a pH of around 7-8. The stirrer speed has a significant effect on the dissolution rate of Mg(OH)2. The highest obtained Mg2+ concentration level was 0.424 mol L-l for the 470 rpm and 0.387 mol L-1 for the 560 rpm which corresponded to the processing time of 45 mins and 40 mins respectively. The particle size distribution shows that the average particle size keeps increasing during the reaction as the CO2 is been fed to the system. The carbonation process is kinetically favored and simple as nesquehonite formation occurs in a very short time. It is a thermodynamically and chemically stable solid product, which allows for a long-term storage of CO2. Since the carbonation reaction is a complex system which includes dissolution of magnesium hydroxide particles, absorption of CO2, chemical reaction and crystallization, the dissolution of magnesium hydroxide was studied in hydrochloric acid (HCl) solvent with and without nitrogen (N2) inert gas. It was found on the dissolution part that the impeller speed had effect on the dissolution rate. The higher the impeller speed the higher the pH of the solution, although for the highest speed of 650rpm it was not the case. Therefore, it was concluded that the optimum speed of the stirrer was 560rpm. The influence of inert gas N2 on the dissolution rate of Mg(OH)2 particles could be seen based on measured pH, electric conductivity and Mg2+ concentration curves.

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More than one decade after the external debt restructuring (the Brady Plan), a great amount of literature has been published concerning the balance sheet factors in developing countries. The staff of international multilateral institutions joined with reputable academics in this great controversy. The external debt problem of the developing countries is back and once more reflections on its cause and on policy recommendations are analytically distinct. Our main task is to reflect on the recent external debt dynamics and assess how this debt has evolved. Our findings indicate that the susceptibility of some developing countries to default is associated with global imbalance, that is, the way they borrow.

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The present paper examines the Brazilian experience from the 'Economic Miracle' to the 'Lost Decade'. Its aim is to advance an alternative measurement of the flows of extraordinary wealth (i.e. ground-rent and net external credit) available for appropriation in the Brazilian economy and to asses their relevance in sustaining the process of accumulation of industrial capital. That is done in order to provide further and more accurate evidence to the claim that the evolution of the Brazilian process of capital accumulation has been extremely dependent on the evolution of those masses of extraordinary wealth.

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The purpose of this study is to explore how scenarios can be exploited in strategic assessment of the external business environment. One of the key challenges for managers worldwide is to adapt their businesses to the ever-changing business environment. As the companies’ external business environment is constantly presenting new opportunities and threats, it is extremely important that companies continuously monitor the possible changes happening around it. As the speed of change rises, assessing the future has become more and more vital. The study was conducted as an exploratory research and the research strategy was influenced by scenario planning and case study strategy. The study examined the European pet food sector from the future point of view. Qualitative study was chosen as research approach and empirical data was collected primarily by seven expert interviews. The secondary data about the sector was applied as complementary empirical data. In the theoretical part of the research it was discovered that nowadays, traditional analysis frameworks are ill-suited for strategic assessment of the external business environment. This is why a self-created combination framework for analysis was employed both as study’s theoretical framework and analysis technique. Furthermore, the framework formed the base for interview questions. Both in theoretical and the empirical part of the study it was found that today, in strategic assessment of the external business environment, besides setting focus on the current situation, it is important to concentrate also on the future. The traditional analysis frameworks offer a good starting point for collecting relevant data but they do not encourage conducting a deeper analysis. By adding characteristics from scenario planning to these more traditional tools, a new analysis framework was created, which ensured the more comprehensive analysis. By understanding the interconnections between discovered phenomena and changes, and by recognizing uncertainties, the user is helped to reflect the environment more profoundly. The contributions of the study are both theoretical and managerial. A new analysis framework strives to answer to the current needs for strategic assessment of external business environment and the framework was tested in the context of European pet food sector. When it comes to managerial contributions, the importance lies in understanding the future. Managers must take future into account and understand that future includes various possibilities which all must be reflected

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Establishing of export operations is the key to the competitiveness for all producing companies in high-tech industry. Distribution partnerships between exporting producer and local distributors of relevant foreign market are utilized by SMEs to gain cost-efficiency of operation. The purpose of this study was to investigate the Swiss market of outdoor lighting solutions and propose distribution channels for the case of company C2 SmartLight Ltd. The literature framework consists of three main parts: description of distribution channels for business products, the selection process of the distributor and management of the distributors. The empirical part of this study composed of the observation of Swiss lighting market, highlighting key customers, trends of energy efficiency and key industry players of the lighting market. The aim was to identify potential distribution channels, which reach the target customer groups and identify the market opportunity. Secondly, the data was collected through semi-structured phone interviews. The company, which operates in outdoor lighting business and has an established distributor in Switzerland, was interviewed and used as a benchmark. As a result of this research the market opportunity for distribution of C2 SmartLight products was identified based on potential customers and market need. C2 SmartLight Ltd. should establish a connection with wholesalers that distribute easy to handle and store electrical equipment. The results of this study can be used by other SME companies, operating in a similar field of economy, for selection of distributors.

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In order to reach the 2°C climate target, the carbon price should rise significantly in order for it to be financially rewarding for companies to reduce their emissions. This research aims to find how a significant increase in the carbon price would affect the profitability of companies. Prior research has not found consensus on how regulatory policies affect companies. This research looks at profitability factors of carbon pricing through a mix of related issues such as the carbon risk, carbon pricing mechanisms and cost pass-through of additional costs. The research is quantitative and examines financial data and emissions data regarding scope 1 and scope 2 emissions on 328 European companies. The data analysis method utilised is a sensitivity analysis conducted as a scenario analysis. Different price increases and cost pass-through rates are tested to see how company profitability is affected. As the companies are distributed between 9 sectors and 53 industries, the results vary. The industries that are found to be affected by an increase in carbon pricing show drastic negative changes in profitability. The results complement prior research identifying the most carbon-intensive industries, but also provide some new insights on industries that may be affected by carbon pricing. Industries related to manufacturing, electricity and energy are partly significantly impacted, but also industries related to tourism and food show potential signs of impact when an increased carbon price is introduced.

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Low levels of ionizing radiation induce two translocation responses in soybean: a reduction in photoassimilate export from leaves and a change in the distribution pattern of exported photoassimilate within the plant. In this investigation these responses have been further studied specifically to ascertain the site of radiation damage and to better understand the physiological responses observed. Experimentally the primary data was obtained from studies in which a mature trifoliate leaf of a young soybean plant (Glycine ~ L. cultivar Harosoy '63) is isolated in a closed transparent chamber and allowed to photoassimilate 14C02 for 15 minutes. This is followed by an additional 45 ~_il'1;ute period before the plant is sectl.o ne d an d 14 C-ra dl' oactl.v.l ty d eterml. ne d'l n a 11 parts. Such 14c data provides one with the magnitude and distribution pattern of translocation. Further analyses were conducted to determine the relative levels of the major photosynthetic products using the techniques of paper chromatography and autoradiography. Since differences between control and irradiated P 1 ants were not 0 b serve d l' n t h e par tl't"lo nlng 0 f 14 C between the 80% ethanol-soluble and -insoluble fractions 14 or in the relative amounts of C-products of photosynthesis, the reduction in export in irradiated plants is not likely due to reduced availability of translocatable materials. Data presented in this thesis shows that photoassimilate export was not affected by gamma radiation until a threshold dose between 2.0 and 3.0 krads was reached. It was also observed that radiation-induced damage to the export process was capable of recovery in a period of 1 to 2 hours provided high light intensity was supplied. In contrast, the distribution pattern was shown to be extremely radiosensitive with a low threshold dose between .25 and .49 krads. Although this process was also capable of recovery,lt" occurred much earlier and was followed by a secondary effect which lasted at least for the duration of the experiments. The data presented in this thesis is interpreted to suggest that the sites of radiation action for the two translocation responses are different. In regards to photoassimilate export, the site of action of ionizing radiation is the leaf, quite possibly the process of photophosphorylation which may provide energy directly for phloem loading and for membrane integrity of the phloem tissue* In regards to the pattern of distribution of exported photoassimilate, the site is likely the apical sink, possibly the result of changes of levels of endogenous hormones. By the selection of radiation exposure dose and time post-irradiation, it is possible to affect independently these two processes suggesting that each may be regulated independent of the other and involves a distinct site.

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The influence of carbon dioxide on growth and protein synthesis of etiolated Avena coleoptiles was investigated. Evidence is presented that 0.03% carbon dioxide stimulated both these processes; and that carbon dioxide stimulated growth depends on carbon dioxide stimulated protein synthesis, In addition the evidence indicates that carbon dioxide stimulated growth is mediated by metabolism, and that carbon dioxide stimulates growth through a dark fixation process. Growth studies also demonstrated that IAA and carbon dioxide stimulated growth in a synergistic manner.

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The phosphonium salt room temperature ionic liquid tetradecyltrihexylphosphonium chloride (THPC) has been employed as an efficient reusable media for the palladium catalyzed Suzuki cross-coupling reaction of aryl halides, including aryl chlorides, under mild conditions. The cross-coupling reactions were found to proceed in THPC containing small amounts ofwater and toluene (single phase) using potassium phosphate and 1% Pd2(dba)3'CHCI3. Variously substituted iodobenzenes, including electron rich derivatives, reacted efficiently in THPC with a variety of arylboronic acids and were all complete within 1 hour at 50°C. The corresponding aryl bromides also reacted under these conditions with the addition of a catalytic amount of triphenylphosphine that allowed for complete conversion and high isolated yields. The reactions involving aryl chlorides were considerably slower, although the addition of triphenylphosphine and heating at 70°C allowed high conversion of electron deficient derivatives. Addition of water and hexane to the reaction products results in a triphasic system, from which the catalyst was then recycled by removing the top (hexanes) and bottom (aqueous) layers and adding the reagents to the ionic liquid which was heated again at 50°C; resulting in complete turnover of iodobenzene. Repetition of this procedure gave the biphenyl product in 82-97% yield (repeated five times) for both the initial and recycled reaction sequences. IL ESTERIFICATIONREACTION A new class oftrialkylphosphorane has been prepared through reaction of a trialkylphosphine with 2-chlorodimethylmalonate in the presence oftriethylamine. These new reagents promote the condensation reaction of carboxylic acids with alcohols to provide esters along with trialkylphosphine oxide and dimethylmalonate. The condensation reaction of chiral secondary alcohols can be controlled to give either high levels of inversion or retention through a subtle interplay involving basicity of the reaction media, solvent, and tuning the electronic and steric nature of the carboxylic acid and stenc nature of the phosphorane employed. A coherent mechanism is postulated to explain these observations involving reaction via an initial acyloxyphosphonium ion.