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81.
Paula Cristina Castro Andrade José Aurélio Medeiros da Luz Arlindo Sales Campos Hernani Mota de Lima 《Clean Technologies and Environmental Policy》2016,18(2):483-492
Both open pit mine and smelter projects can have significant impacts on a variety of environmental resources. Among these, air quality of the surroundings is a key issue. Additionally, the environmental assessment of projects demands integrated approach taking in account all pollution sources. Therefore, specific focus has been put on the methodology for assessing impacts on air quality. This paper proposes an integrated index of environmental impact aiming to quantify the air quality impact of industrial operations around an urban area, in case of scarcity of in situ acquired data. This proposed pollution index is demonstrated by a case study conducted in the municipality of Congonhas, Brazil, in which contributions of five open pit mines and two smelters were studied. To achieve the pollution index, the wind rose and distances from the centroids of effective areas to the urban nucleus itself were considered, taking into account the wind projection areas from windward impacting sources on the leeward impacted urban site. The proposed index also includes the squared wind speed (proportional to the kinetic energy transferred in uplifting dust from ground surface). The method proposed is considered suitable for impact assignment for each one of the air pollution sources in the neighborhood of studied area. Some fluid dynamic aspects of airborne particulate matter are also studied by proposing a new equation for threshold saltation speed. 相似文献
82.
Michał Piegza Danuta Witkowska Regina Stempniewicz 《Journal of the Institute of Brewing》2014,120(4):341-346
Geotrichum candidum yeasts are proposed as a starter culture during malting. They have a double positive effect on the process. They eliminate the fungal pathogenic microflora and improve the technological properties of the finished product, malt. Among published research little or no information can be found considering the biosynthesis of hydrolytic enzymes. Most of the data is related to the production of lipases, proteases and cellulases. This paper examines the enzymology of a number of G. candidum strains. The main focus within the evaluation process was placed on whole cell barley grain cultivation. Hydrolase, which is present in cell wall degradation, was found at a satisfactory level. All tested strains produced both β‐1,3‐glucanases and β‐1,4‐glucanases capable of hydrolysing barley β‐glucan and reducing the amount of this polysaccharide in the wort. Molecular analysis of the tested strains with the use of restriction fragment length polymorphism–polymerase chain reaction and randomly amplified polymorphic DNA confirmed not only the species affiliation, but also the genetic similarity between the tested strains. Copyright © 2014 The Institute of Brewing & Distilling 相似文献
83.
Roque S. Soares Regina C. C. Monteiro Maria M. R. A. Lima Bogdan A. Sava Mihail Elisa 《Journal of Materials Science》2014,49(13):4601-4611
The crystallization kinetics and phase transformation of a transparent Tb3+-doped lithium–aluminum phosphate glass, prepared by melt quenching, were investigated. The energy associated to the glass transition and the crystallization parameters (activation energy for crystallization and Avrami exponent) were evaluated by different methods using the experimental data obtained by differential thermal analysis performed at different heating rates. Using an isoconversional method to determine the change of the activation energy for crystallization with the fraction of crystallization, it was verified that with the increase in the fraction of crystallization from 0.1 to 0.9, the value of the activation energy decreased slightly from ~370 to ~310 kJ mol?1 and that the Avrami exponent varied from 0.8 to 1, suggesting a surface crystal growth mechanism. Observation of the microstructural evolution of heat-treated glass samples confirmed a surface crystallization process revealing spherulitic crystals constituted mainly by aluminum metaphosphate. 相似文献
84.
85.
Wieslaw J. Bochenek Peter Weber Regina Slowinska Gexin Tang John B. Rodgers 《Lipids》1990,25(10):665-668
Monosaccharide composition was determined in apolipoprotein B-48 (apoB) of chylomicrons of rat mesenteric lymph. Chylomicrons
were separated into three fractions based on density. Triglyceride and apolipoprotein content were determined in each. ApoB
was isolated and quantified using precipitation with isopropanol. Chylomicrons were collected in lymph under normal conditions,
and with Poloxalene 2930 when chylomicron secretion was inhibited. Most of the triglyceride was carried in the least dense
fraction, while the highest apoB content was in the most dense fraction under normal conditions. Mannose and galactosamine
contents of apoB were similar in all fractions while contents of both glucosamine and galactose were highest in the least
dense fraction. When chylomicron secretion was inhibited by Poloxalene, the amount of triglyceride recovered in the least
dense fraction was significantly reduced. Despite the inhibition of lipid transport in the least dense fraction of chylomicrons
by Poloxalene, there was little change in apoB recoveries and in the relative content of various monosaccharides in the apoB
from each of the three fractions as compared to results obtained during lipid absorption under normal conditions. In conclusion,
carbohydrate composition of apoB of chylomicrons is heterogeneous and varies with chylomicron density. 相似文献
86.
87.
The study of journal authorship and editorial board membership from a gender perspective is addressed in this paper following international recommendations about the need to obtain science and technology indicators by gender. Authorship informs us about active scientists who contribute to the production and dissemination of new knowledge through journal articles, while editorial board membership tells us about leading scientists who have obtained scientific recognition within the scientific community. This study analyses by gender the composition of the editorial boards of 131 high-quality Spanish journals in all fields of science, the presence of men and women as authors in a selection of 36 journals, and the evolution of these aspects from 1998 to 2009. Female presence is lower than male presence in authorship, editorial board membership and editorship. The presence of female authors is slightly lower than the presence of women in the Spanish Higher Education sector and doubles female presence in editorial boards, which mirrors female presence in the highest academic rank. The gender gap tends to diminish over the years in most areas, especially in authorship and very slightly in editorial board membership. Large editorial boards and having a female editor-in-chief are positively correlated with women presence in editorial boards. The situation of women in Spanish science is further assessed in an international context analysing a selection of international reference journals. The usefulness of journal-based indicators to monitor the situation of men and women in science and to assess the success of policies oriented to enhance gender equality in science is finally discussed. 相似文献
88.
Ergonomic stress levels, personal characteristics, accident occurrence and sickness absence among factory workers 总被引:3,自引:0,他引:3
This study was designed to evaluate the association of a single, integrated measure of simultaneous exposure to a number of adverse work and environmental conditions, termed the Ergonomic Stress Level (E-S-L), on workers' accident and sickness absence rates. The factors determining the E-S-L were body motion and posture, physical effort, active hazards and environmental stressors. E-S-L evaluation was based on 'walk-through' hazard inventories, direct observations, measurements and interviews. Workers were assigned to one of four stress levels ranging from low (A) to high (D). Subjects were 729 males, aged 20-67 years, employed in five factories in Israel. A linear relationship between E-S-L AND accident incidence was found, increasing from the lowest to the highest E-S-L. Moreover, workers more sensitive to environmental stressors, as indicated by their reported subjective annoyance, showed higher accident rates across all the ergonomic stress levels, a tendency which was statistically significant at levels C and D. On the other hand, sickness absence was significantly related to the overall subjective stress experienced, as manifested by reported job dissatisfaction and somatic complaints, and not directly to E-S-L. These findings highlight the role of aggregate work stress, coupled with individual sensitivity to environmental stressors, in increasing the risk of accidents. 相似文献
89.
The monosaccharide and polyalcohol composition of 28-samples of different commercial tannins, including oak wood, grape seed and skin, plant gall, chestnut, quebracho and gambier, has been evaluated by gas chromatography–mass spectrometry after derivatization into their trimethylsilyl ethers. Quercitol was found to be characteristic of oak tannins, whereas gall plant tannins could be differentiated by their content of pinitol. Myo-inositol and arabitol were detected in tannins from quebracho. These polyalcohols, together with muco-inositol and chiro-inositol, were found in tannins from chestnut while bornesitol was found to be characteristic of tannins from gambier. Monosaccharide composition also helped to distinguish among tannin origins: arabinose, xylose, fructose and glucose were quantified in oak, quebracho and chestnut tannins, whereas only fructose and glucose were detected in plant gall and grape tannins. These results imply that the qualitative study of monosaccharides and polyalcohols could help to determine and control the authenticity of enological tannins. 相似文献
90.
Wheat flour from the Hermosillo Hard Red Spring cultivar in Sonora, Mexico was fortified with various levels of lysine and methionine. The effects of added amino acids on the rheological properties were measured by the Brabender Farinograph and the Chopin Alveograph. Nutritional characteristics were measured by Protein Efficiency Ratio (PER). Dough development and stability times were not significantly different between control and fortified flours. Water absorption and Alveograph results indicated differences between samples. PERs were significantly improved by fortification. Overall bread acceptability was not significantly different from unfortified samples. 相似文献