922 resultados para Reduction of smoke components yield


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Kuumahiertoprosessi on erittäin energiaintensiivinen prosessi, jonka energianominaiskulutus (EOK) on yleisesti 2–3.5 MWh/bdt. Noin 93 % energiasta kuluu jauhatuksessa jakautuen niin, että kaksi kolmasosaa kuluu päälinjan ja yksi kolmasosa rejektijauhatuksessa. Siksi myös tämän työn tavoite asetettiin vähentämään energian kulutusta juuri pää- ja rejektijauhatuksessa. Päälinjan jauhatuksessa tutkimuskohteiksi valittiin terityksen, tehojaon ja tuotantotason vaikutus EOK:een. Rejektijauhatuksen tehostamiseen pyrittiin yrittämällä vähentää rejektivirtaamaa painelajittelun keinoin. Koska TMP3 laitoksen jauhatuskapasiteettia on nostettu 25 %, tavoite oli nostaa päälinjan lajittelun kapasiteettia saman verran. Toisena tavoitteena oli pienentää rejektisuhdetta pää- ja rejektilajittelussa ja siten vähentää energiankulutusta rejektijauhatuksessa. Näitä tavoitteita lähestyttiin vaihtamalla päälinjan lajittimiin TamScreen-roottorit ja rejektilajittimiin Metso ProFoil-roottorit ja optimoimalla kuitufraktiot sihtirumpu- ja prosessiparametrimuutoksin. Syöttävällä terätyypillä pystyttiin vähentämään EOK:ta 100 kWh/bdt, mutta korkeampi jauhatusintensiteetti johti myös alempiin lujuusominaisuuksiin, korkeampaan ilmanläpäisyyn ja korkeampaan opasiteettiin. Myös tehojaolla voitiin vaikuttaa EOK:een. Kun ensimmäisen vaiheen jauhinta kuormitettiin enemmän, saavutettiin korkeimmillaan 70 kWh/bdt EOK-vähennys. Tuotantotason mittaamisongelmat heikensivät tuotantotasokoeajojen tuloksia siinä määrin, että näiden tulosten perusteella ei voida päätellä, onko EOK tuotantotasoriippuvainen vai ei. Päälinjan lajittelun kapasiteettia pystyttiin nostamaan TS-roottorilla vain 18 % jääden hieman tavoitetasosta. Rejektilajittelussa pystyttiin vähentämään rejektimäärää huomattavasti Metso ProFoil-roottorilla sekä sihtirumpu- ja prosessiparametrimuutoksin. Lajittamokehityksellä saavutettu EOK-vähennys arvioitiin massarejektisuhteen pienentymisen ja rejektijauhatuksessa käytetyn EOK:n avulla olevan noin 130 kWh/bdt. Yhteenvetona voidaan todeta, että tavoite 300 kWh/bdt EOK-vähennyksestä voidaan saavuttaa työssä käytetyillä tavoilla, mikäli niiden täysi potentiaali hyödynnetään tuotannossa.

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The energy balance for the production of sunflower oil and cake was carried out during the agricultural and industrial stage phase, where it was considered a cold extraction by hydraulic pressing, with the plant location in a rural area with a radius of 30km range. Data on productivity was used in two varieties of sunflower (Helio 358 and Aguará 04) grown in different seasons (2007/2008, 2008/2009), under different irrigation levels. Data showed that irrigation resulted in an increase in productivity of both varieties, and the best response was observed for Aguará 04 variety. Moreover, the increased intensity of irrigation negatively affected the energy balance, reducing the ratio between energy produced and energy used in the production chain. The most significant inputs in the energy intake were fertilizer followed by diesel oil, when irrigation was not used for. When the irrigation technique was used, the most significant inputs, in order of representativeness, were: energy, fertilizer and equipment.

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This study was carried out to determine some physiological and phenological responses of the bean under high [CO2] and drought stress. The experiment was conducted from April to July 2009 in Viçosa, Brazil. The open-top chambers were used to enrich the air with CO2, whereas the drought stress was applied between the flowering and the ripening. The randomized block design was used, with four replicates in the subplots. The following plots were [CO2] at 700ppm (F1) and [CO2] environmental (F2) and the subplots were well watering (S1) and drought stress (S2). The results were subjected to Anova and the Tukey test (P < 0.05). For the treatments F1S1 and F1S2 the photosynthetic rate showed increments of 59% and the transpiration reduction of 12%. The yield, leaf temperature and stomatal conductance were not significant different to high [CO2], different from the dry matter, who showed increment of 20% (F1S1) and the water use efficiency who showed increase of 90% for high [CO2]. The osmotic potential was lower in plants under drought stress (F2S2 and F1S2), followed by plants under high [CO2] (F1S1). Despite the increment in photosynthesis, high [CO2] does not guarantee higher yield.

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OBJECTIVE: to evaluate the role of fibrillar extracellular matrix components in the pathogenesis of inguinal hernias. METHODS: samples of the transverse fascia and of the anterior sheath of the rectus abdominis muscle were collected from 40 men aged between 20 and 60 years with type II and IIIA Nyhus inguinal hernia and from 10 fresh male cadavers (controls) without hernia in the same age range. The staining technique was immunohistochemistry for collagen I, collagen III and elastic fibers; quantification of fibrillar components was performed with an image analysis processing software. RESULTS: no statistically significant differences were found in the amount of elastic fibers, collagen I and collagen III, and the ratio of collagen I / III among patients with inguinal hernia when compared with subjects without hernia. CONCLUSION: the amount of fibrillar extracellular matrix components did not change in patients with and without inguinal hernia.

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Growing concerns about toxicity and development of resistance against synthetic herbicides have demanded looking for alternative weed management approaches. Allelopathy has gained sufficient support and potential for sustainable weed management. Aqueous extracts of six plant species (sunflower, rice, mulberry, maize, brassica and sorghum) in different combinations alone or in mixture with 75% reduced dose of herbicides were evaluated for two consecutive years under field conditions. A weedy check and S-metolachlor with atrazine (pre emergence) and atrazine alone (post emergence) at recommended rates was included for comparison. Weed dynamics, maize growth indices and yield estimation were done by following standard procedures. All aqueous plant extract combinations suppressed weed growth and biomass. Moreover, the suppressive effect was more pronounced when aqueous plant extracts were supplemented with reduced doses of herbicides. Brassica-sunflower-sorghum combination suppressed weeds by 74-80, 78-70, 65-68% during both years of study that was similar with S-metolachlor along half dose of atrazine and full dose of atrazine alone. Crop growth rate and dry matter accumulation attained peak values of 32.68 and 1,502 g m-2 d-1 for brassica-sunflower-sorghum combination at 60 and 75 days after sowing. Curve fitting regression for growth and yield traits predicted strong positive correlation to grain yield and negative correlation to weed dry biomass under allelopathic weed management in maize crop.

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Different nitrogen oxide removal technologies for rotary lime kiln are studied in this thesis, the main focus being in commercial technologies. Post-combustion methods are investigated in more detail as potential possible NOx removal with combustion methods in rotary lime kiln is more limited or primary methods are already in use. However, secondary methods as NOx scrubber, SNCR or SCR technologies are not listed as the Best Available Technologies defined by European Union. BAT technologies for NOx removal in lime kiln are (1) Optimised combustion and combustion control, (2) Good mixing of fuel and air, (3) Low-NOx burner and (4) Fuel selection/low-N fuel. SNCR method is the most suitable technique for NOx removal in lime kiln when NOx removal from 50 % to 70 % is required in case primary methods are already in use or cannot be applied. In higher removal cases ammonia slip is an issue in SNCR. By using SCR better NOx reduction can be achieved but issues with catalyst materials are expected to arise because of the dust and sulphur dioxide which leads to catalyst poison formation in lower flue gas temperatures. NOx scrubbing has potential when simultaneous NOx and SO2 removal is required. The challenge is that NO cannot be scrubbed directly, but once it is oxidized to NO2 or further scrubbing can be performed as the solubility of NO2 is higher. Commercial installations have not been made regarding SNCR, SCR or NOx scrubbing regarding rotary lime kiln. For SNCR and SCR the closest references come from cement industry.

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Most studies suggest that serotonin exerts an inhibitory control on the aggression process. According to experimental evidence, this amine also influences growth and development of the nervous tissue including serotoninergic neurons. Thus, the possibility exists that increased serotonin availability in young animals facilitates a long-lasting effect on aggressive responses. The present study aimed to investigate the aggressive behavior of adult rats (90-120 days) treated from the 1st to the 19th postnatal day with citalopram (CIT), a selective serotonin reuptake inhibitor (20 mg/kg, sc, every 3 days). Aggressive behavior was induced by placing a pair of rats (matched by weight) in a box (20 x 20 x 20 cm), and submitting them to a 20-min session of electric footshocks (five 1.6-mA - 2-s current pulses, separated by a 4-min intershock interval). When compared to the control group (rats treated for the same period with equivalent volumes of saline solution), the CIT group presented a 41.4% reduction in the duration of aggressive response. The results indicate that the repeated administration of CIT early in life reduces the aggressive behavior in adulthood and suggest that the increased brain serotoninergic activity could play a role in this effect.

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This study explored the reduction of adenosine triphosphate (ATP) levels in L-02 hepatocytes by hexavalent chromium (Cr(VI)) using chi-square analysis. Cells were treated with 2, 4, 8, 16, or 32 μM Cr(VI) for 12, 24, or 36 h. Methyl thiazolyl tetrazolium (MTT) experiments and measurements of intracellular ATP levels were performed by spectrophotometry or bioluminescence assays following Cr(VI) treatment. The chi-square test was used to determine the difference between cell survival rate and ATP levels. For the chi-square analysis, the results of the MTT or ATP experiments were transformed into a relative ratio with respect to the control (%). The relative ATP levels increased at 12 h, decreased at 24 h, and increased slightly again at 36 h following 4, 8, 16, 32 μM Cr(VI) treatment, corresponding to a "V-shaped" curve. Furthermore, the results of the chi-square analysis demonstrated a significant difference of the ATP level in the 32-μM Cr(VI) group (P < 0.05). The results suggest that the chi-square test can be applied to analyze the interference effects of Cr(VI) on ATP levels in L-02 hepatocytes. The decreased ATP levels at 24 h indicated disruption of mitochondrial energy metabolism and the slight increase of ATP levels at 36 h indicated partial recovery of mitochondrial function or activated glycolysis in L-02 hepatocytes.

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A recent study showed that miR-26a is downregulated in hepatocellular carcinoma tissues and that this downregulation is an independent predictor of survival. Interestingly, the same study also reported that miR-26a downregulation causes a concomitant elevation of IL-6 expression. Because miR-26a expression was found to be transcriptionally downregulated by oncogene c-Myc in various cancers, and the expression of c-Myc was increased by IL-6 stimulation, we hypothesized that IL-6 contributes to reduction of miR-26a in hepatocellular carcinoma. Serum IL-6 was measured by ELISA and miR-26a was detected by qRT-PCR. The data of 30 patients with hepatocellular carcinoma who had undergone surgical tumor resection revealed that serum IL-6 could be considered to be a predictor of survival up to 5 years for hepatocellular carcinoma patients (log-rank test, P < 0.05). We observed that the serum IL-6 concentration was inversely correlated with miR-26a expression in cancerous tissues (Pearson correlation test, r = -0.651, P < 0.01). Furthermore, by in vitro experiments with HepG2 cells, we showed that IL-6 stimulation can lead to miR-26a suppression via c-Myc activation, whereas in normal hepatocyte LO2 cells incubation with IL-6 had no significant effect on miR-26a expression. Taken together, these results indicate that miR-26a reduction in hepatocellular carcinoma might be due to IL-6 upregulation.

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The objective of this prospective study was to determine the plasma levels of nitric oxide (NO) in women with chronic pelvic pain secondary to endometriosis (n=24) and abdominal myofascial pain syndrome (n=16). NO levels were measured in plasma collected before and 1 month after treatment. Pretreatment NO levels (μM) were lower in healthy volunteers (47.0±12.7) than in women with myofascial pain (64.2±5.0, P=0.01) or endometriosis (99.5±12.9, P<0.0001). After treatment, plasma NO levels were reduced only in the endometriosis group (99.5±12.9 vs 61.6±5.9, P=0.002). A correlation between reduction of pain intensity and reduction of NO level was observed in the endometriosis group [correlation = 0.67 (95%CI = 0.35 to 0.85), P<0.0001]. Reduction of NO levels was associated with an increase of pain threshold in this group [correlation = -0.53 (-0.78 to -0.14), P<0.0001]. NO levels appeared elevated in women with chronic pelvic pain diagnosed as secondary to endometriosis, and were directly associated with reduction in pain intensity and increase in pain threshold after treatment. Further studies are needed to investigate the role of NO in the pathophysiology of pain in women with endometriosis and its eventual association with central sensitization.

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This study proposes alternatives to the current methods of processing round-cooked lobster. The paralyzation of lobsters with direct electric shock consumes 10.526 x 10-3 kWh, which is significantly less than the 11 kWh required by the traditional thermal-shock method (based on 60 kg of lobsters). A better weight gain was obtained by immersion of paralyzed lobsters in brine before cooking. Systematic trials combining 3, 6, or 9% brine concentrations with immersion periods of 15, 30, or 45 minutes were performed in order to determine the best combinations. A mathematical model was designed to predict the weight gain of lobsters of different sizes in any combination of treatments. For small lobsters, a 45 minutes immersion in 6% brine gave the best response in terms of weight gain (4.7%) and cooking produced a weight loss of only 1.34% in relation to fresh lobster weight. For medium-sized lobsters, a 45 minutes immersion in 9% brine produced a weight gain of 2.64%, and cooking a weight gain of 1.08%. For large lobsters, a 45 minutes immersion in 6% brine produced a weight gain of 3.87%, and cooking a weight gain of 1.62%.

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Cardiovascular diseases (CVD) are the main causes of death in the Western world. Among the risk factors that are modifiable by diet, for reducing cardiovascular disease risks, the total plasma concentrations of cholesterol, triglycerides, LDL-C, and HDL-C are the most important. Dietary measures can balance these components of the lipid profile thus reducing the risk of cardiovascular diseases. The main food components that affect the lipid profile and can be modified by diet are the saturated and trans fats, unsaturated fats, cholesterol, phytosterols, plant protein, and soluble fiber. A wealth of evidence suggests that saturated and trans fats and cholesterol in the diet raise the total plasma cholesterol and LDL-C. Trans fats also reduce HDL-C, an important lipoprotein for mediating the reverse cholesterol transport. On the other hand, phytosterols, plant proteins, isoflavones, and soluble fiber are protective diet factors against cardiovascular diseases by modulating plasma lipoprotein levels. These food components at certain concentrations are able to reduce the total cholesterol, TG, and LDL-C and raise the plasma levels of HDL-C. Therefore, diet is an important tool for the prevention and control of cardiovascular diseases, and should be taken into account as a whole, i.e., not only the food components that modulate plasma concentrations of lipoproteins, but also the diet content of macro nutrients and micronutrients should be considered.

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The carcass fast freezing is one of the aspects of great prominence to the final quality of pork. In order to reduce weight loss, two experiments were performed, in which the carcasses were monitored during 20 hours to evaluate the main variables involved during two different freezing processes (standard and proposed) as follows: microbiological quality, storage temperature, relative humidity (RH) and air velocity. In experiment I, the carcasses were submitted to a system using heat shock (2 hours in static tunnel at - 25 °C) and subsequently sent to the equalization chamber. In experiment II, the carcasses were submitted to the heat shock and stored in a chamber with RH between 80-85%. The chambers used in both experiments showed no change in the variables studied (internal temperature of 5 °C and air velocity of approximately 0.3 m/s). However, the relative humidity in the three chambers was evaluated and significant differences were found; as a consequence, high levels of weight loss were observed in both chambers In experiment II there was an increase of RH, which reduced the weight loss of the carcasses.

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Canadian honeys were analyzed for sugar concentration, honey colour, total phenolic content, the level of brown pigments, and antioxidant activity in order to elucidate the main components involved in the antioxidant activity of honey. By employing size-exclusion chromatography in combination with activity-guided fractionation, it was demonstrated that the antioxidant components are of high molecular weight (HMW), brown in colour and absorb at both 280nm and 450nm. The presence of brown HMW antioxidant components prompted an investigation on the influence of heattreatment on the Maillard reaction and the formation of melanoid ins. Heat-treatment of honey resulted in an increase in the level of phenolics in the melanoidin fractions which correlated with an increase in antioxidant activity. The preliminary results of this study suggest for the first time that honey melanoidins underlie the antioxidant activity of unheated and heat-treated honey, and that phenolic constituents are involved in the melanoidin structure and are likely incorporated by covalent or non-covalent interaction.