972 resultados para Technical efficiency


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This paper presents the results of a research on direct drinking water treatment through an ultrafiltration pilot plant unit using spiral-wound membranes (3500 MWCO). The source of water is the Guarapiranga Reservoir, an eutrophicated water body located in the metropolitan region of Sao Paulo, Brazil. The data were collected during a period of almost 3400 h, from August 2005 to January 2006. The main objective of the study was to evaluate the membrane production capacity and contaminant removal efficiency. It was verified that the system was able to produce a high quality permeate with a flow close to the specified by the membrane manufacturer. The average permeate flow was 19.7 L.h(-1).m(-2), at 467 kPa and 25 degrees C, with a global water recovery of almost 85%. The removal efficiencies for TOC, UV light absorption, and turbidity were 85%, 56%, and 95%, respectively. The results provide substantial evidence of the technical feasibility of spiral-wound UF membranes for direct drinking water treatment from euthrophicated sources, as an alternative for conventional drinking water treatment systems.

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At present, the cement industry generates approximately 5% of the world`s anthropogenic CO(2) emissions. This share is expected to increase since demand for cement based products is forecast to multiply by a factor of 2.5 within the next 40 years and the traditional strategies to mitigate emissions, focused on the production of cement, will not be capable of compensating such growth. Therefore, additional mitigation strategies are needed, including an increase in the efficiency of cement use. This paper proposes indicators for measuring cement use efficiency, presents a benchmark based on literature data and discusses potential gains in efficiency. The binder intensity (bi) index measures the amount of binder (kg m(-3)) necessary to deliver 1 MPa of mechanical strength, and consequently express the efficiency of using binder materials. The CO(2) intensity index (ci) allows estimating the global warming potential of concrete formulations. Research benchmarks show that bi similar to 5 kg m(-3) MPa(-1) are feasible and have already been achieved for concretes >50 MPa. However, concretes with lower compressive strengths have binder intensities varying between 10 and 20 kg m(-3) MPa(-1). These values can be a result of the minimum cement content established in many standards and reveal a significant potential for performance gains. In addition, combinations of low bi and ci are shown to be feasible. (c) 2010 Elsevier Ltd. All rights reserved.

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Plantation spacing selection has the primary objective of assigning each tree enough space for maximum growth and best quality to be attained with a minimum cost. From the harvest standpoint, an increase in stand density directly implies a decrease of individual tree volume, reducing also harvester productive capacity. The objective of this research is to assess the effects of several initial spacings and arrangements in eucalyptus plantations on production capacity, operational capacity and costs of forest harvester. Real operational data were collected from two eucalypt plantations at different initial spacing of 6.0, 7.5, 9.0, 12 and 18 m(2) per tree. Simulation data were obtained from a forest harvester simulator. Using spacing (E), mean tree volume (MV), diameter at breast height (DBH) and height (H) values, a stepwise regression test procedure was run, and correlations computed in order to measure their participation in operational capacity. Operational costs were computed with an accounting method proposed by FAO. Mean tree volume (MV) explained 88% of forest harvester operational capacity. Spacing (E) affected 8.5% of harvester operational capacity; wider spacings were related to higher individual tree volumes. Harvesting operation costs were lower in wider spaced treatments.

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Xylella fastidiosa (Wells, Raju, Hung, Weisburg, Mandelco-Paul, and Brenner) is a bacteria] pathogen transmitted by several Sharpshooters in two tribes of Cicadellinae (Proconiini and Cicadellini). Here, we compared the transmission efficiency of X. fastidiosa in coffee (Coffea arabica L) and citrus [Citrus sinensis (L) Osbeck] by Cicadellini [Bucephalogonia xanthophis (Berg) and Dilobopterus costalimai Young] and Proconiini [Homalodisca ignorata Melichar and Oncometopia facialis (Signoret) I sharpshooters that Occur in both crops. At different seasons, healthy adults of each species were submitted to a 48-h acquisition access period on citrus or coffee source plants infected with X. fastidiosa isolates that cause Citrus variegated chlorosis (CVC) and Coffee leaf scorch (CLS), respectively, and then confined on healthy seedlings of the corresponding host plant for a 48-h inoculation access period. No significant effect of inoculation season was observed when comparing infection rates of citrus or coffee plants inoculated by vectors at different times of the year. In Citrus, the transmission rate by single insects was significantly higher for H. ignorata (30%) in relation to B. xanthophis (5%) and O. facialis (1.1%) but there was no difference among vector species in coffee, whose transmission rates ranged from 1.2 to 7.2%. Comparing host plants, H. ignorata was more effective in transmitting X. fastidiosa to citrus (30%) in relation to coffee (2.2%), whereas the other vectors transmitted the bacterium to both hosts with similar efficiencies. Despite these variations. vector efficiency in coffee and Citrus is lower than that reported in other hosts.

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Due to the rapid depletion of water resources, water must be used more efficiently in agriculture to maintain current levels of yield in irrigated areas. The efficiency of irrigation systems can be increased by adjusting the amount of water applied to specific conditions of soil and crop, which may vary in a field. Taking into account spatial and temporal variability, it is evident that an equipment capable of providing different irrigation levels is necessary to meet the water requirement of the soil. This work aims to develop and evaluate a flow rate sprinkler to be used in center pivots or linear moving irrigation systems, with potential for utilization in irrigation scheduling. A prototype was developed by duplicating its calibrations, and discharge coefficient adjustment was carried out in the laboratory. To predict the flow rate, a successful model that represented the operation of the flow rate sprinkler was established. The calibration of the flow rate sprinkler prototype showed satisfactory statistical and technical results. Automation of the prototype was achieved by driving a step motor using communication from the parallel port of a microcomputer, which was controlled by a software developed for this purpose. The results were satisfactory and technically feasible.

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The success in the adoption of peach integrated production (IP) was evaluated in small orchards of the Parana State. The importance of specific technical accompaniment; points of strangulating in adoption of technology and the classification of the areas to IP conformity were evaluated. The seasons 2005/2006 (without IP orientation) and 2006/2007 (with IP orientation) were compared considering 20 producers who were oriented monthly to attend the minimum requisites. The incidence of peach rust (Tranzschelia discolor) and of brown rot (Monilinia fructicola) in full bloom was evaluated in 2006/2007 and 2007/2008 seasons, as biological parameters to accompany the efficiency of system adoption. After the technical accompaniment in 2007/2008 season, the software APOIA-Novo Rural-PI (APOIA-PI) was applied to measure the conformity to IP in peach orchards. The conformity index of each orchard was compared to the minimum requisite to classify as IP (0.7). The major difficulties in register of field book were: pests monitoring; collect of climate data and the harvest evaluation. The technical accompaniment increased in 60% the conformity in use of field book. In 2007/2008 season, the brown rot incidence increased in some areas, caused by not following IP recommendations. The inadequate management caused the increment in pathogen inoculum, promoting the disease development in peach orchards. The APOIA-PI classified two orchards as good agricultural practices (GAP) (0.7 <= conformity index >= 0.4), two as integrated production (IP) (>= 0.7) and the other orchards had conformity index lower than 0.4.

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The objectives of this study were to determine if percentage Bos taurus (0 or 50%) of the cow had an effect on ME requirements and milk production, and to compare cow/calf efficiency among 3 mating systems. Metabolizable energy requirements were estimated during a feeding trial that encompassed a gestation and lactation feeding trial for each of 2 groups of cows. Cows were 0 or 50% Bos taurus ( 100 or 50% Nellore) breed type: Nellore cows (NL; n = 10) mated to Nellore bulls, NL cows ( n = 9) mated to Angus bulls, Angus x Nellore (ANL; n = 10) and Simmental x Nellore (SNL; n = 10) cows mated to Canchim (5/ 8 Charolais 3/ 8 Zebu) bulls. Cows were individually fed a total mixed diet that contained 11.3% CP and 2.23 Mcal of ME/kg of DM. At 14-d intervals, cows and calves were weighed and the amount of DM was adjusted to keep shrunk BW and BCS of cows constant. Beginning at 38 d of age, corn silage was available to calves ad libitum. Milk production at 42, 98, 126, and 180 d postpartum was measured using the weigh-suckle-weigh technique. At 190 d of age, calves were slaughtered and body composition estimated using 9-10-11th-rib section to obtain energy deposition. Regression of BW change on daily ME intake (MEI) was used to estimate MEI at zero BW change. Increase in percentage Bos taurus had a significant effect on daily ME requirements (Mcal/d) during pregnancy (P < 0.01) and lactation (P < 0.01). Percentage Bos taurus had a positive linear effect on maintenance requirements of pregnant (P = 0.07) and lactating (P < 0.01) cows; during pregnancy, the ME requirements were 91 and 86% of those in lactation (131 +/- 3.5 vs. 145 +/- 3.4 Mcal.kg(-0.75).d(-1)) for the 0 and 50% B. taurus groups, respectively. The 50% B. taurus cows, ANL and SNL, suckling crossbred calves had greater total MEI (4,319 +/- 61 Mcal; P < 0.01) than 0% B. taurus cows suckling NL (3,484 +/- 86 Mcal) or ANL calves (3,600 +/- 91 Mcal). The 0% B. taurus cows suckling ANL calves were more efficient (45.3 +/- 1.6 g/Mcal; P = 0.03) than straightbred NL (35.1 +/- 1.5 g/Mcal) and ANL or SNL pairs (41.0 +/- 1.0 g/Mcal). Under the conditions of this study, crossbreeding improved cow/ calf efficiency and showed an advantage for cows that have lower energy requirements.

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Potassium (K) is an essential nutrient for higher plants. Information on K uptake and use efficiency of upland rice under Brazilian conditions is limited. A greenhouse experiment was conducted with the objective to evaluate influence of K on yield, K uptake, and use efficiency of six upland rice genotypes grown on Brazilian Oxisol. The K rate used was zero (natural soil level) and 200 mg K kg-1 of soil. Shoot dry weight and grain yield were significantly influenced by K level and genotype treatments. However, K x genotype interactions were not significant, indicating similar responses of genotypes at two K levels for shoot dry weight and grain yield. Genotypes produced grain yield in the order of BRS Primavera BRA 01596 BRSMG Curinga BRS 032033 BRS Bonanca BRA 02582. Potassium concentration in shoot was about sixfold greater compared to grain, across two K levels and six genotypes. However, K utilization efficiency ratio (KUER) (mg shoot or grain yield / mg K uptake in shoot or root) was about 6.5 times greater in grain compared to shoot, across two K level and six genotypes. Potassium uptake in shoot and grain and KUER were significantly and positively associated with grain yield. Soil calcium (Ca), K, base saturation, acidity saturation, Ca saturation, K saturation, Ca/K ratio, and magnesium (Mg)/K ratio were significantly influenced by K application rate.

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With the aim to study the water efficiency on the muskmelon hydroponics during a long cycle of crop and with different intervals between irrigation was carried out an experiment in two season from October 2003 to January 2004 (season I) and from January to April (season II). The experiment was carried out on the Fitotecnia Department on the Universidade Federal of Santa Maria, Santa Maria, RS. Were determined the water consumptions on the growth of the plants to observe the water efficiency. The water efficiency was a maximum on the blossom phase (4.19g de FS m(-3)) on the season I and on the vegetative phase (8.22g de FS m(-3)) for season II, associated with an elevated growth rate and small water consumptions on these seasons.

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This study reports the effects of dietary iron (Fe) deficiency and recovery on bone mineral composition and strength in anemic rats submitted to a hemoglobin (Hb) repletion assay. Weanling male Wistar rats were fed a low-Fe diet (12 mg/kg) for 15 days followed by 2 weeks of Fe repletion with diets providing 35 mg Fe/kg as either ferrous sulfate (n = 8) or ferric pyrophosphate (FP; n = 12). At final day of each period (depletion and repletion), Fe-adequate animals were also euthanized. Iron status (blood Hb, Hb Fe pool, Hb regeneration efficiency), tibia mineral concentrations (Ca, Mg, Fe, Cu, and Zn) and biomechanical properties were evaluated. Iron-deficient rats had lower tibia Fe and Mg levels and bone strength when compared to controls. Yield load and resilience were positively related to tibia Mg levels (r = 0.47, P = 0.02 and r = 0.56, P = 0.004, respectively). Iron repletion did not recover tibia Mg concentrations impaired by Fe deficiency. Moreover, bone elastic properties were negatively affected by FP consumption. In conclusion, bone mineral composition and strength were affected by Fe deficiency, whereas dietary Fe source influenced tibia Mg and resistance in the period during which rats were recovering from anemia.

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The Brazilian Network of Food Data Systems (BRASILFOODS) has been keeping the Brazilian Food Composition Database-USP (TBCA-USP) (http://www.fcf.usp.br/tabela) since 1998. Besides the constant compilation, analysis and update work in the database, the network tries to innovate through the introduction of food information that may contribute to decrease the risk for non-transmissible chronic diseases, such as the profile of carbohydrates and flavonoids in foods. In 2008, data on carbohydrates, individually analyzed, of 112 foods, and 41 data related to the glycemic response produced by foods widely consumed in the country were included in the TBCA-USP. Data (773) about the different flavonoid subclasses of 197 Brazilian foods were compiled and the quality of each data was evaluated according to the USDAs data quality evaluation system. In 2007, BRASILFOODS/USP and INFOODS/FAO organized the 7th International Food Data Conference ""Food Composition and Biodiversity"". This conference was a unique opportunity for interaction between renowned researchers and participants from several countries and it allowed the discussion of aspects that may improve the food composition area. During the period, the LATINFOODS Regional Technical Compilation Committee and BRASILFOODS disseminated to Latin America the Form and Manual for Data Compilation, version 2009, ministered a Food Composition Data Compilation course and developed many activities related to data production and compilation. (C) 2010 Elsevier Inc. All rights reserved.

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This article presents an evaluation of the effects of the spouted bed design and operating conditions on system fluiddynamics and process performance during enteric coating of hard gelatine capsules. The design parameters studied were the column diameter (150 mm and 200 mm), the included angle of the conical base, gamma (60 degrees or 40 degrees) and the presence or absence of a Venturi inserted before the inlet air orifice. The process variables studied were the ratio between the feed flow rate of the coating suspension to the spouting gas flow rate (W(s)/W(g)), the mass of capsules loaded to the equipment (M(0)), and the ratio between the Spouting gas flow rate to the gas flow rate at minimum spouting condition (Q/Q(ms)). The response variables were the rate of increase of the capsules mass (K(1)), and the adhesion efficiency (eta). The linear regression equation for the dependent variable K, in terms of the independent variables adequately described the process with an r(2) value of 0.872. Analysis of variance (ANOVA) revealed that increasing of W(s)/W(g), Q/Q(ms) and gamma significantly increased the adhesion efficiency. Adhesion efficiencies higher than 90% were achieved by selecting precise coating conditions, indicating the feasibility of the process for coating of hard gelatine capsules. (C) 2008 Elsevier B.V. All rights reserved.

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Degradation of Disperse Orange 1, Disperse Red 1 and Disperse Red 13 dyes has been performed using electrochemical oxidation on Pt electrode, chemical chlorination and photoelectrochemical oxidation on Ti/TiO(2) thin film electrodes in NaCl or Na(2)SO(4) medium. 100% discoloration was obtained for all tested methods after 1 h of treatment. Faster color removal was obtained by photoelectrocatalytic oxidation in 0.1 mol L(-1) NaCl pH 4.0 under UV light and an applied potential of +1.0V (vs SCE reference electrode), which indicates also values around 60% of TOC removal. The conventional chlorination method and electrochemical oxidation on Pt electrode resulted in negligible reduction of TOC removal. All dyes showed positive mutagenic activity in the Salmonella/microsome assay with the strain TA98 in the absence and presence of S9 (exogenous metabolic activation). Nevertheless, there is complete reduction of the mutagenic activity after 1 h of photoelectrocatalytic oxidation, suggesting that this process would be good option to remove disperse azo dyes from aqueous media. (C) 2008 Elsevier Ltd. All rights reserved.

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This study is an integral part of a research project which seeks the establishment of protocols for the production of standardized herbal dried extracts emphasizing the spouted bed drying. This thesis was conducted at faculty of Pharmaceutical Science of Ribeiro Preto/University of So Paulo, Brazil, under supervision of Prof. Dr. Wanderley Pereira Oliveira*, defended on September 28, 2007.

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This technical appendix details the methods used in an assessment of the potential of snus for tobacco harm reduction using simulation modelling.