Relevant bibliographies by topics / Collecte de fraction

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Academic literature on the topic 'Collecte de fraction'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Collecte de fraction"

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Ratchamak, R., T. Vongpralub, W. Boonkum, and V. Chankitisakul. "Cryopreservation and quality assessment of boar semen collected from bulk samples." Veterinární Medicína 64, No. 5 (May 28, 2019): 209–16. http://dx.doi.org/10.17221/125/2018-vetmed.

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The purpose of this study was to examine sperm quality after cryopreservation of ejaculates collected as a bulk sample, which is routinely part of semen collection, and to compare this quality with the sperm-rich fraction in boars. Ejaculates were collected as sperm-rich fractions (SRF) and bulk samples (BE) using a gloved-hand technique. Fresh semen quality in terms of semen volume, sperm concentration, total sperm motility and pH were conventionally evaluated. Then, semen was cryopreserved using the liquid nitrogen vapour method. The post-thaw sperm quality was evaluated by assessing sperm motility, live sperm with normal apical ridge and high mitochondrial energy status, lipid peroxidation was evaluated using CASA and fluorescent multiple staining and MDA levels were determined using a spectrophotometer, respectively. In terms of fresh semen quality, sperm motility in fresh semen did not differ significantly between the two groups. The treatment with the greater mean volume (BE; P < 0.05) had a lower mean sperm concentration (P < 0.05); meanwhile, the mean ejaculate pH collected as BE was more basic compared with SRF (P < 0.05). However, there were no significant post-thaw quality changes between sperm-rich fractions and bulk samples of semen. In conclusion, ejaculates can be collected as bulk samples without the need to classify fractions for boar semen cryopreservation.
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Lupo, Cristina, Samy Boulos, and Laura Nyström. "Influence of Partial Acid Hydrolysis on Size, Dispersity, Monosaccharide Composition, and Conformation of Linearly-Branched Water-Soluble Polysaccharides." Molecules 25, no. 13 (June 29, 2020): 2982. http://dx.doi.org/10.3390/molecules25132982.

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The effect of partial acid hydrolysis on the physical and chemical properties of galactomannan, arabinoxylan, and xyloglucan was investigated. Polysaccharides were treated at 50 °C with hydrochloric acid for 3–48 h. Portions of isopropanol (i-PrOH) were added sequentially to the hydrolyzates, resulting in fractions that were collected by centrifugation. As expected, a significant reduction of weight-average molecular weight (Mw) was observed with increasing hydrolysis time. Fractional precipitation was successfully applied to collect at least one polymer fraction with dispersity (Đ) close to one for each polysaccharide. The monosaccharide composition analysis showed that the partial hydrolysis usually lowered the relative amount of side chains, with the exception of galactomannan, where the composition remained largely unaffected. Estimation of the polymer conformation in solution, through evaluation of the Mark-Houwink parameter coefficient (α), confirmed that acid hydrolysis influenced the polysaccharides’ conformation. It was demonstrated that acid treatment in dilute solution followed by fractional isopropanol precipitation is a method, extendible to a variety of polysaccharides, to obtain materials of decreased molecular weight and low dispersity with slightly altered overall composition and conformation.
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Manilal, Aseer, Sugathan Sujith, Balu Sabarathnam, George Seghal Kiran, Joseph Selvin, Chippu Shakir, and Aaron Premnath LIPTON. "Bioactivity of the red algae Asparagopsis taxiformis collected from the Southwestern coast of India." Brazilian Journal of Oceanography 58, no. 2 (June 2010): 93–100. http://dx.doi.org/10.1590/s1679-87592010000200002.

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Among the diverse variety of red algae, Asparagopsis taxiformis constitutes one of the abundant biomass in the Kollam coast (Southwest coast of India). Therefore, in the present study, A. taxiformis was collected, extracted and fractionated using column chromatography. The individual fractions were evaluated in vitro for their antifouling, anticyanobacterial, piscicidal and crustaceans toxicity assays. The fraction eluted with 2:8, petroleum ether and ethyl acetate exhibited strong and broad spectrum of bioactivity. In antifouling assay against Limnea truncatula, the active algal fraction produced 80% of foot repellency at 150 mg/L whereas in anticyanobacterial assay, the active fraction inhibited 100% growth of Trichodesmium sp. at 320 mg/L. The algal fraction showed higher piscicidal effect at the level of 60 mg/L. The crustacean toxicity of the active fraction was also evaluated to find compounds without toxicity in non target organisms, Penaeus monodon and Macrobrachium rosenbergii. It was found that column fraction showed less toxicity against the non target organisms. The chemical constituents of the active fraction were identified by means of chromatographic systems such as TLC, reverse phase HPLC and GC-MS. The overall activity profile envisages that the active column fraction of A. taxiformis might contain synergistic bioactive metabolites that could be utilized for the control of fouling organisms, algal bloom and herbivorous/predaceous fishes in aquaculture ponds.
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Deringöl, Yasemin. "Misconceptions of primary school students about the subject of fractions: views of primary teachers and primary pre-service teachers." International Journal of Evaluation and Research in Education (IJERE) 8, no. 1 (March 1, 2019): 29. http://dx.doi.org/10.11591/ijere.v8i1.16290.

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<span>This study was conducted with the aim of investigating the current knowledge of Primary Teachers and Primary Pre-service Teachers on the misconceptions of primary school students about the subject of fractions. The qualitative research method of case study was used to conduct the research. The data were collected with semi-structured forms that were developed by the researcher to collect the views of Primary Teachers and Primary Pre-service Teachers on the topic. The participants stated that, regarding the subject of fractions, primary school students had difficulties the most in representing fractions by models, the concepts of denominator and numerator, when they need to rank fractions, when they need to solve problems, reading and writing concepts that express fractions, distinguishing types of fractions – converting these, showing a given fraction on number lines and operations on fractions, and they had misconceptions about these.</span>
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Tojo, A., and H. Endou. "Intrarenal handling of proteins in rats using fractional micropuncture technique." American Journal of Physiology-Renal Physiology 263, no. 4 (October 1, 1992): F601—F606. http://dx.doi.org/10.1152/ajprenal.1992.263.4.f601.

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Previous micropuncture studies on protein handling along the nephron could not exclude the possibility of contamination by extratubular proteins. Thus we developed a fractional micropuncture method. Renal tubules were punctured with an outer puncture pipette, into which an inner collection pipette was inserted repeatedly to collect tubular fluid, usually up to four fractions. The albumin concentration of tubular fluid was highest in the first fraction and gradually decreased to a constant level, indicating physiological albumin concentrations. On the other hand, low-molecular-weight protein (LMWP) concentrations showed no significant difference among the four fractions. By plotting the protein delivery in the fourth fraction along the nephron, glomerular filtrated protein concentrations were estimated by extrapolating the tubular fluid-to-plasma inulin concentration ratio into one. The glomerular filtrated albumin was 22.9 micrograms/ml (0.00062 in filtration coefficient), and that of LMWP was 72.1 (0.988). Albumin was almost evenly reabsorbed in early (37%) and late (34%) proximal convoluted tubules and the straight tubules (23%). On the other hand, LMWP was more strongly reabsorbed in the early proximal convoluted tubules (54%) than in the late ones (28%) or the straight portion (5%). The fractional micropuncture procedure provides direct evidence of protein handling along the nephron without extratubular protein contamination.
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Hearne, C. E., D. L. Johnson, and H. Van Campen. "Immunogold-Silver Staining (IGSS) of (NCP and CP) BVDV Infected Subcellular Fraction Bands." Microscopy and Microanalysis 3, S2 (August 1997): 155–56. http://dx.doi.org/10.1017/s1431927600007662.

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Pre-embedding immunogold-silver (IGSS) techniques are useful to localize antigens in cell monolayers and agarose embedded cell suspensions for transmission electron microscopy. Procedural centrifugations, however, present a challenge when attempting to localize antigens in subcellular fractions. Using a Beckman Airfuge Ultracentrifuge to concentrate the subcellar fraction bands and resuspending the organelles in agarose simplifies IGSS processing and resin embedding procedures.Control bovine turbinate (BT), and BT cells infected with cytopathic (cp NADL) and non-cytopathic (ncp NY-1) strains of bovine viral diarrhea virus (BVDV) were fractioned according to Bienz et al (1992). Bands containing membrane vesicles (Fig 2) were collected and each fraction band was pelleted at 169,000g for 20 min using an A-95 fixed angle rotor in a Beckman Airfuge Ultracentrifuge. Each fraction pellet was resuspended in 50μl of 30% agarose, solidified, and trimmed to < lmm. IGSS procedures were carried out according to Nanoprobes, Inc., Stoney Brook, NY, and Hearne & Van Campen (1996).
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Mota, Jaedson Cláudio Anunciato, Carlos Eduardo Linhares Feitosa, Lucas de Sousa Oliveira, José Israel Pinheiro, Alfredo Mendonça de Sousa, Thiago Leite de Alencar, Márcio Godofrêdo Rocha Lobato, Alexandre dos Santos Queiroz, and Ícaro Vasconcelos do Nascimento. "Pipette Method: Errors Resulting From Aliquot Collection Depth in Soil Clay Quantification." Journal of Agricultural Science 11, no. 2 (January 15, 2019): 244. http://dx.doi.org/10.5539/jas.v11n2p244.

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Granulometry represents the relative proportions of the fractions that compose the soil, being an important agronomic tool to infer mean values of density, water availability and cation exchange capacity, besides being useful in soil classification. Among the methods employed to determine the fractions composing the soil, those which consider the separation by sedimentation for the clay fraction still have problems in the analytical protocol, which are directly responsible of errors in the results obtained. Given the above, this study aimed to evaluate the best pipette immersion depth to collect the aliquot containing only clay, to calculate and discuss the errors associated with collection of the aliquot containing clay fraction in soil granulometric analysis. Samples for granulometric analysis were collected in the superficial layer and top of the B horizon of an Argissolo Amarelo, corresponding to the textural classes sandy loam and sandy clay. Regardless of soil textural class, the depth h = 5 cm established in the calculation using the Stokes&rsquo;s equation leads to overestimation and underestimation of clay and silt fractions in the soil. The collection should be performed with the pipette tip positioned at h/2 = 2.5 cm.
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Teoh, Sian Hoon, Siti Syardia Erdina Mohamed, Parmjit Singh, and Liew Kee Kor. "IN SEARCH OF STRATEGIES USED BY PRIMARY SCHOOL PUPILS FOR DEVELOPING FRACTION SENSE." Malaysian Journal of Learning and Instruction 17, Number 2 (July 31, 2020): 25–61. http://dx.doi.org/10.32890/mjli2020.17.2.2.

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Purpose – Most literature has focused solely on either knowledge about number sense or understanding of fractions. To fill the research gap, this study examined pupils’ abilities in both number sense and fractions. In particular, it investigated Year 4 and Year 5 pupils’ use of strategies in developing their fraction sense. Methodology – This study adopted a descriptive research design, utilising a mixed approach in data collection. An instrument called the Fraction Sense Test (FST) and a clinical interview were used to collect data. The FST comprised 3 strands: fraction concept, fraction representation and effect of operation. A two-stage cluster sampling method was employed to select 396 Year 4 and Year 5 pupils. The sampling involved random selection of the primary schools in the first stage, followed by pupils within the selected schools in the second stage. In addition to descriptive statistics, content analysis of interview transcripts was conducted to identify the presence of concepts and strategies applied among the pupils. Findings – The study found that the pupils scored lowest in effect of operation. It was also revealed that there were four strategies which helped the pupils to develop fraction sense, namely (1) comparing fractions using benchmark fractions of common fractions such as ½, ¼, zero and 1, (2) understanding denominators to determine the size of equal parts, (3) comparing fractions using unit fraction, and (4) applying the strategies in (1) and (2) to manipulate fractions in effect of operation. Significance – The findings provide useful input to facilitate the development of fraction sense ability.
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Xu, Shiwei, Yanting Shen, and Yonghui Li. "Antioxidant Activities of Sorghum Kafirin Alcalase Hydrolysates and Membrane/Gel Filtrated Fractions." Antioxidants 8, no. 5 (May 15, 2019): 131. http://dx.doi.org/10.3390/antiox8050131.

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Sorghum has a significant amount of proteins, especially kafirin; however, limited information is available on evaluating its potential for peptide antioxidants. The objectives of this study were to: (1) investigate the effects of two key variables, enzyme-to-substrate ratio and reaction time on kafirin hydrolysis using Alcalase; (2) evaluate the antioxidant performances of the hydrolysates and fractions from membrane ultrafiltration and gel filtration; and (3) identify peptide sequences in the antioxidant fraction using MALDI-TOF/TOF MS. Kafirin hydrolysates prepared at enzyme-to-substrate ratio of 0.4 Au/g and 4 h had a good balance of antioxidant activity, yield, and economic efficiency. Medium-sized fraction of hydrolysates (5–10 kDa) from membrane filtration possessed the highest antioxidant activities among various fractions. The fraction also unveiled a good inhibition effect against lipid oxidation in emulsion and ground meat systems. Smaller-sized fraction (F3) collected through gel-filtration chromatography had significantly stronger antioxidant activities than other fractions, and 26 representative peptide sequences were identified in the fraction.
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Liu, Yalong, Ping Wang, Yuanjun Ding, Haifei Lu, Lianqing Li, Kun Cheng, Jufeng Zheng, et al. "Microbial activity promoted with organic carbon accumulation in macroaggregates of paddy soils under long-term rice cultivation." Biogeosciences 13, no. 24 (December 15, 2016): 6565–86. http://dx.doi.org/10.5194/bg-13-6565-2016.

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Abstract. While soil organic carbon (SOC) accumulation and stabilization has been increasingly the focus of ecosystem properties, how it could be linked to soil biological activity enhancement has been poorly assessed. In this study, topsoil samples were collected from a series of rice soils shifted from salt marshes for 0, 50, 100, 300 and 700 years from a coastal area of eastern China. Soil aggregates were fractioned into different sizes of coarse sand (200–2000 µm), fine sand (20–200 µm), silt (2–20 µm) and clay (< 2 µm), using separation with a low-energy dispersion protocol. Soil properties were determined to investigate niche specialization of different soil particle fractions in response to long-term rice cultivation, including recalcitrant and labile organic carbon, microbial diversity of bacterial, archaeal and fungal communities, soil respiration and enzyme activity. The results showed that the mass proportion both of coarse-sand (2000–200 µm) and clay (< 2 µm) fractions increased with prolonged rice cultivation, but the aggregate size fractions were dominated by fine-sand (200–20 µm) and silt (20–2 µm) fractions across the chronosequence. SOC was highly enriched in coarse-sand fractions (40–60 g kg−1) and moderately in clay fractions (20–25 g kg−1), but was depleted in silt fractions (∼ 10 g kg−1). The recalcitrant carbon pool was higher (33–40 % of SOC) in both coarse-sand and clay fractions than in fine-sand and silt fractions (20–29 % of SOC). However, the ratio of labile organic carbon (LOC) to SOC showed a weakly decreasing trend with decreasing size of aggregate fractions. Total soil DNA (deoxyribonucleic acid) content in the size fractions followed a similar trend to that of SOC. Despite the largely similar diversity between the fractions, 16S ribosomal gene abundance of bacteria and of archaeal were concentrated in both coarse-sand and clay fractions. Being the highest generally in coarse-sand fractions, 18S rRNA gene abundance of fungi decreased sharply but the diversity gently, with decreasing size of the aggregate fractions. The soil respiration quotient (ratio of respired CO2–C to SOC) was the highest in the silt fraction, followed by the fine-sand fraction, but the lowest in coarse-sand and clay fractions in the rice soils cultivated over 100 years, whereas the microbial metabolic quotient was lower in coarse-sand-sized fractions than in other fractions. Soil respiration was higher in the silt fraction than in other fractions for the rice soils. For the size fractions other than the clay fraction, enzyme activity was increased with prolonged rice cultivation, whereas soil respiration appeared to have a decreasing trend. Only in the coarse-sand fraction was both microbial gene abundance and enzyme activity well correlated to SOC and LOC content, although the chemical stability and respiratory of SOC were similar between coarse-sand and clay fractions. Thus, biological activity was generally promoted with LOC accumulation in the coarse-sand-sized macroaggregates of the rice soils, positively responding to prolonged rice cultivation management. The finding here provides a mechanistic understanding of soil organic carbon turnover and microbial community succession at fine scale of soil aggregates that have evolved along with anthropogenic activity of rice cultivation in the field.
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Dissertations / Theses on the topic "Collecte de fraction"

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Alexander, Cathleen Marie. "Community college developmental education students' understanding of foundational fraction concepts." Thesis, University of California, Davis, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3614168.

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Mathematics, in general, and algebra courses, in particular, have been categorized as "gatekeepers" for higher education, better jobs, and even citizenship. For many low-income and working adults, community college is the institution where they choose to develop their mathematics understanding so they can pursue their dreams. Unfortunately many fail in their attempts. In an effort to better understand their plight so that the community colleges can better meet their needs, I studied community college students' foundational fraction understanding. Specifically, I examined students' procedural skills and problem-solving strategies to determine evidence of fragmented knowledge and fragile learning. I investigated a sample of 373 adult students in four tiers of community college developmental education mathematics courses: Computational Arithmetic, Pre-Algebra, Beginning Algebra, and Intermediate Algebra. In Phase 1, I quantitatively examined students' performance on a written assessment of foundational fraction problems. I compared groups of students to determine if differences might be due to factors of course level, age, and number of years out of school. In Phase 2, I interviewed 33 of the lowest performing students and examined their explanations and categorized students' problem-solving strategies and levels of procedures and explanations while using the strategies. My analysis revealed five major findings. 1. Students' average score on an 11-item foundational fraction assessment was 74%, below what I considered mastery level on the assessment. 2. The assessment scores differed based on course level rather than other demographic factors. 3. On specific NAEP items, Algebra and Intermediate Algebra students scored similarly to United States eighth-graders, whereas Arithmetic and Pre-Algebra students scored higher than 4th graders yet lower than eighth-graders. 4. The foundational fraction items related to magnitude tended to be the most difficult for the students. 5. The major characteristics of students' conceptual understanding were fragmented, fragile, non-fluent and only rarely, sophisticated. While community college developmental education students know something about fractions, my research indicated that their knowledge was held as multiple unconnected knowledge chunks, bits and pieces of prior knowledge mixed with inaccurate, imprecise and partial notions and procedures making students' resulting "fraction sense" tenuous. Although they sometimes successfully solved problems, occasionally with sophisticated self-generated strategies, students were not fluent in their fraction knowledge. The dissertation ends with some recommendations for instructors to address students' limited fraction understanding along with some suggestions for the system as a whole to make fraction instruction a greater priority in developmental courses so that more students can achieve their goals.

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Paterno-Mahler, Rachel. "Determining the AGN fraction of galaxy groups." Pomona College, 2007. http://ccdl.libraries.claremont.edu/u?/stc,17.

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Using the Chandra X-ray Observatory, Martini et al. (2006) found that the AGN fraction of galaxy clusters was five times higher than previous optical studies suggested. Using visual observations only, Dressler et al. (1985) estimated the AGN fraction of field galaxies to be 5%, while that of clusters was thought to be 1%. To understand the role that the environment plays in AGN fueling, the author studied a variety of environments, ranging from the field to groups to clusters. Will the AGN fraction of groups also be higher than that of the field? The author demonstrates how the AGN fraction of groups compares to that of clusters. In the following sections, the author describes the mechanics of X-ray astronomy, the group environment, and the characteristics of active galactic nuclei. The author briefly describes the possible mechanisms for AGN fueling.
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Kadhi, TauGamba. "Online assessment: a study of the validation and implementation of a formative online diagnostic tool in developmental mathematics for college students." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4361.

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This Research and Design (R&D) study models the methodology necessary to replicate an online assessment instrument designed to assess student skills and facets of thought while understanding Multiple Meanings and Models of Fractions (MUL) in college level developmental mathematics. The researcher used cognitive research done in the area of fractions to design this instrument that both documents and assesses facets of thought or reasoning strategies used by students. The final facet cluster is a table that ranks these facets from least to most problematic, documenting the student facets of thought across the content objective MUL. Over 500 student and teacher participants were used in the design and development of Fraction Diagnoser. All participants were affiliated with college developmental mathematics in Texas, representing four colleges and universities. Forty-eight student participants were individually interviewed to ascertain facets of understanding on the topic of MUL. Seven teacher participants were individually interviewed as to the effectiveness of Fraction Diagnoser in the classroom after the final step of the R&D cycle. Content experts were used to design the questions assessing skills and facets. Fraction Diagnoser was built using the Borg and Gall R&D cycle as its blueprint. Nine of the ten steps of the R&D cycle were used in the development of the instrument, excluding just the final product revision due to cost and time restraints. According to Borg and Gall (1996), a dissertation R&D should be limited to a few steps, but all of the steps used for this R&D allowed for the researcher to completely address all of the research questions. During the steps of the R&D cycle, validation and reliability analyses were done to statistically address the effectiveness of Fraction Diagnoser. Final interviews with the teacher participants supported findings in recent research on the effective use of online assessment. Implications for practice and recommendations for further study were also addressed.
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Roblet, Cyril Roland. "Fractionnement d'un hydrolysat de protéines de soya : Comparaison des technologies baro-membranaire (UF) et électro-membranaire (ÉDUF) pour la collecte de fractions bioactives." Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/29016/29016.pdf.

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Turner, Sylvia A. "The effects of a constructivist-based fraction intervention on the achievement and self-efficacy beliefs of low socio-economic status students." Scholarly Commons, 2012. https://scholarlycommons.pacific.edu/uop_etds/26.

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Low socio-economic status (SES) students are less likely to gain access to the gatekeeper mathematics courses necessary for high school graduation and entrance to college. This study examined the effects of a constructivist-based fraction intervention on mathematics achievement, self-efficacy beliefs, and Algebra One enrollment of mathematically at risk low SES sixth grade students. Students' fifth grade mathematics CST and sixth grade fraction benchmark scores served as covariates in each analysis. Achievement was measured by the students' scores on their seventh grade fraction benchmark and mathematics California Standards Test (CST). A Fraction Self-Efficacy Survey measured students' beliefs. The sixth grade fraction intervention was a one week, 35 hour program. The experiment included 45 students who attended the intervention and 43 matched students who served as the comparison group. Teacher effects were controlled. The scores of students in the treatment group were significantly higher on both their seventh grade fraction benchmark (p < 0.001) and mathematics CST (p < 0.001). Students in the treatment group scored higher in overall self-efficacy beliefs than students in the comparison group and, although there was a trend towards significance (p = 0.065), the difference was not statistically significant. Additionally, logistic regression was used to determine that students' self-efficacy beliefs partially mediated the relationship between participation in the fraction intervention and their enrollment in Algebra One. Students who attended the intervention were three times as likely to enroll in Algebra One as their matched peers.
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Silva, Rainolenes de Melo. "A corretagem de im?veis no Rio Grande do Norte: das pr?ticas hist?ricas ? emerg?ncia como segmento integrante da fra??o imobili?ria do capital." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13643.

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Made available in DSpace on 2014-12-17T14:20:04Z (GMT). No. of bitstreams: 1 RainolenesMS_DISSERT.pdf: 2942907 bytes, checksum: 5c9161e3e9ad850202c86adb4b846590 (MD5) Previous issue date: 2011-09-21
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
This research proposed to question the development of what was defined as historical practices (commercial, social and political institutions), of the economic activity of the real estate brokerage in the Rio Grande do Norte from the progressive institutionalization of economic agents - individuals (realtors) and legal (real estate) - based on two main approaches: a) the development of economic activity as an integral segment of a fraction of capital (POULANTZAs, 1985; LESSA, 1981). This work set out from a socio-historical approach of the historical practices development the of real estate brokerage in Brazil started in the Southeast, especially in the cities of Rio de Janeiro and S?o Paulo as a result of the "expansion of capitalist relations by the housing sector" (RIBEIRO , 1996). especially the real estate capital ; b) the historical development of relations between labor and capital within the activity, in other words, the development of the relationship between realtors and Real Estate in relation to "group of interests" and their "collective actions" (OFFE, 1984). These historical practices are defined in this research as: 1) mercantile practices, times when there was no distinction between the activity of real estate brokerage and other forms of mercantile capital; 2) social practices, which began in the 1930s, when agents of real estate are to be distinguished from each other within the activity through Taylorist division of labor between workers realtors and developers of real estate; 3) political and institutional practices, initiated in 1962, characterized by State action, in the individualization and distinction of the agents of real estate brokerage as socioprofessional category regulated throughout Brazil by Law 4.116/62 and 6.530/78. The results achieved by the present study showed that in Rio Grande do Norte, due to the specifics as to the peripheral processes of urbanization of the constitution of the land market, as well as the process of conservative modernization of the oligarchic State from the 1960s (CLEMENTINE, 1995; FERREIRA, 1996, 2010, TRINDADE, 2004), the State was led to the development of a late manifestation of the historical practices of real estate brokerage. In other words, it was a process in which historical practices, in particular social practices, not fully developed, mitigating, thus the perception of realtors from his position in the process of exploitation of labor by the Real Estate. And, as a result, of their collective interests front of them.
Esta pesquisa se prop?s a perquirir o desenvolvimento do que foi definido como pr?ticas hist?ricas (mercantis, sociais e pol?tico-institucionalizadas), da atividade econ?mica da corretagem de im?veis no Rio Grande do Norte a partir da progressiva institucionaliza??o de seus agentes econ?micos pessoas f?sicas (corretores de im?veis) e jur?dicas (imobili?rias) com base em dois enfoques principais: a) o desenvolvimento da atividade econ?mica enquanto segmento integrante de uma fra??o de capital (POULANTZAS, 1985; LESSA, 1981), em especial da fra??o imobili?ria do capital ; b) o desenvolvimento hist?rico das rela??es entre o trabalho e o capital no interior da atividade, ou seja, o desenvolvimento das rela??es entre corretores de im?veis e imobili?rias no que tange aos grupos de interesse e de suas a??es coletivas (OFFE, 1984). Este trabalho partiu de uma abordagem socio-hist?rica do desenvolvimento das pr?ticas hist?ricas da corretagem de im?veis no Brasil iniciadas no Sudeste, especialmente nas cidades do Rio de Janeiro e S?o Paulo como resultado do processo de expans?o das rela??es capitalistas pelo setor habitacional (RIBEIRO, 1996). Tais pr?ticas hist?ricas est?o definidas no presente trabalho como: 1) pr?ticas mercantis: momentos em que n?o havia distin??o entre a atividade da corretagem de im?veis e outras manifesta??es do capital mercantil; 2) pr?ticas sociais: iniciadas nos anos de 1930, momento em que os agentes da corretagem de im?veis passam a se distinguir entre si, no interior da atividade atrav?s da divis?o taylorista do trabalho entre trabalhadores corretores de im?veis, e empres?rios das imobili?rias; 3) pr?ticas pol?tico institucionalizadas: iniciadas em 1962 caracterizadas pela a??o do Estado na individualiza??o e distin??o dos agentes da corretagem de im?veis, como categoria socio-profissional regulamentada em todo Brasil pelas Leis 4.116/62 e 6.530/78. Os resultados alcan?ados pelo presente estudo mostraram que no Rio Grande do Norte, em decorr?ncia das especificidades quanto aos processos de urbaniza??o perif?rica da constitui??o do mercado de terras, assim como, do processo de moderniza??o conservadora do Estado Olig?rquico a partir da d?cada de 1960 (CLEMENTINO, 1995; FERREIRA, 1996; 2010; TRINDADE, 2004), o Estado foi levado ao desenvolvimento de uma manifesta??o tardia das pr?ticas hist?ricas da corretagem de im?veis. Em outras palavras, um processo no qual as pr?ticas hist?ricas, em especial as pr?ticas sociais, n?o se desenvolveram plenamente, mitigando, dessa forma, a percep??o dos corretores de im?veis de sua posi??o no processo de explora??o do trabalho pelas imobili?rias. E, como consequ?ncia, de seus interesses coletivos frente ?s mesmas.
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Beaudoin, Marie-Ève. "Développement de méthodes de séparation des oligosaccharides de chitine et de chitosane par électrophorèse capillaire." Thèse, 2005. http://hdl.handle.net/1866/16767.

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Duvall, Rachelle Monique. "Size-resolved chemical composition and water-soluble fraction of atmospheric aerosols collected from the Asian continent." 2002. http://catalog.hathitrust.org/api/volumes/oclc/51555131.html.

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Thesis (M.S.)--University of Wisconsin--Madison, 2002.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 104-106).
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YI, HSU HSIU, and 許秀玉. "The study of the cognitions of the related knowledge in fractions teaching of the Teachers Colleges’ students in Taiwan---Hualien Teachers College was the studying case." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/28216078087224872276.

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碩士
國立花蓮師範學院
國小科學教育研究所
91
The purpose of this study was to investigate how many the students of the Teachers Colleges in Taiwan knew in the related knowledge of fractions teaching. Three items were taken in this study. They were: the knowledge of the fractions, the knowledge of the fractions teaching materials and methods, and the knowledge of the students’ fractions learning. The process of the study was conducted by the pencil and paper tests and by semi-structural one-to-one interviews to collect the data needed. 156 senior students of Hualien Teachers College took the paper tests. Among them, 24 were selected to be interviewed. The data were analyzed, two grading levels---qualified and unqualified were taken, and the results were as follows: 1.In the item of the knowledge of the fractions: 16.03％ was qualified in paper and 8.33％ was qualified in interview, 83.97％ was unqualified in paper and 91.67％ was unqualified in interview. 2.In the item of the knowledge of the fractions teaching materials and methods: 10.26％ was qualified in paper and 25％ was qualified in interview; 89.74％ was unqualified in paper and 75％ was unqualified in interview. 3.In the item of the knowledge of students’ fractions learning: 7.69％ was qualified in paper and 25％ was qualified in interview; 92.3％ was unqualified in paper and 75％ was unqualified in interview.
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Books on the topic "Collecte de fraction"

1

Magin, Richard L. Fractional Calculus in Bioengineering. Begell House Publishers, 2006.

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Fractions, decimals, & percents: GMAT strategy guide. 2014.

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Protocol to estimate mortality from cirrhosis and hepatocellular carcinoma attributable to viral hepatitis B and C. Pan American Health Organization, 2021. http://dx.doi.org/10.37774/9789275123768.

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One of the goals to be achieved by 2030 of the Global Health Sector Strategy on Viral Hepatitis 2016-2021 is to reduce mortality from hepatitis viruses B (HBV) and C (HCV). To measure and monitor it, countries need to implement a systematic process to generate national estimates of mortality from viral hepatitis, which many lack. This document is aimed at the institutions and/or ministries in charge of monitoring progress in each country. The main objective of this protocol is to present simple methods to estimate the proportion of patients with cirrhosis and hepatocellular carcinoma who have HBV and HCV infection, and then calculate the national mortality due to these sequelae attributable to viral hepatitis, preferably within a surveillance system. In addition, a general framework is provided on how the surveillance system should function, how to collect the data, and ethical considerations. The surveillance system will be based on sentinel centers where information will be collected from patients with cirrhosis and hepatocellular carcinoma. These data will be used to estimate the fraction of cirrhosis and hepatocellular carcinoma attributable to HBV and HCV. On the other hand, data will be collected on the number of deaths nationwide from cirrhosis and hepatocellular carcinoma. With this information, mortality from cirrhosis and hepatocellular carcinoma attributable to HBV and HCV will be estimated.
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Shubert, Kurt Francis. A non-metric, non-parametric analysis of the low intertidal epibiota fraction of Prince William Sound data collected during the post-Exxon Valdez oil spill assessment. 1997.

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Wright, A. G. The Photomultiplier Handbook. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199565092.001.0001.

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This handbook is aimed at helping users of PMTs who are faced with the challenge of designing sensitive light detectors for scientific and industrial purposes. The raison d’être for photomultipliers (PMTs) stems from four intrinsic attributes: large detection area, high, and noiseless gain, and wide bandwidth. Detection involves a conversion process from photons to photoelectrons at the photocathode. Photoelectrons are subsequently collected and increased in number by the action of an incorporated electron multiplier. Photon detection, charge multiplication, and many PMT applications are statistical in nature. For this reason appropriate statistical treatments are provided and derived from first principles. PMTs are characterized by a range of photocathodes offering detection over UV to infra-red wavelengths, the sensitivities of which can be calibrated by National Laboratories. The optical interface between light sources and PMTs, particularly for diffuse or uncollimated light, is sparsely covered in the scientific literature. The theory of light guides, Winston cones, and other light concentrators points to means for optimizing light collection subject to the constraints of Liouville’s theorem (étandue). Certain PMTs can detect single photons but are restricted by the limitations of unwanted background ranging in magnitude from a fraction of a photoelectron equivalent to hundreds of photoelectrons. These sources, together with their correlated nature, are examined in detail. Photomultiplier biasing requires a voltage divider comprising a series of resistors or active components, such as FETs. Correct biasing provides the key to linear operation and so considerable attention is given to the treatment of this topic. Electronic circuits and modules that perform the functions of charge to voltage conversion, pulse shaping, and impedance matching are analysed in detail.
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Robb, Thomas K., and David James Gill. Divided Allies. Cornell University Press, 2019. http://dx.doi.org/10.7591/cornell/9781501741845.001.0001.

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By directly challenging existing accounts of post-World War II relations among the United States of America, the United Kingdom, Australia, and New Zealand, this book is a significant contribution to transnational and diplomatic history. At its heart, the book examines why strategic cooperation among these closely allied Western powers in the Asia-Pacific region was limited during the early Cold War. The book probes the difficulties of security cooperation as the leadership of these four states balanced intramural competition with the need to develop a common strategy against the Soviet Union and the new communist power, the People's Republic of China. It exposes contention and disorganization among non-communist allies in the early phase of containment strategy in Asia-Pacific. In particular, it notes the significance of economic, racial, and cultural elements to planning for regional security and highlights how these domestic matters resulted in international disorganization. The book shows that, amidst these contentious relations, the antipodean powers Australia and New Zealand occupied an important role in the region and successfully utilized quadrilateral diplomacy to advance their own national interests, such as the crafting of the 1951 ANZUS collective security treaty. As fractious as were allied relations in the early days of NATO, the book demonstrates that the post-World War II Asia-Pacific was as contentious, and that Britain and the commonwealth nations were necessary partners in the development of early global Cold War strategy.
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Book chapters on the topic "Collecte de fraction"

1

Stieltjes, T. J. "Investigations on Continued Fractions." In Œuvres Complètes Collected Papers, 1175–311. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-61229-9_10.

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Lang, Serge, and Hale Trotter. "Continued fractions for some algebraic numbers." In Collected Papers Volume II, 69–92. New York, NY: Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4612-2120-3_5.

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Gelfand, Izrail Moiseevich. "Fractional powers of operators and Hamiltonian systems." In Collected Papers, 610–24. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-61705-8_32.

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Lang, Serge. "Continued Fractions for Some Algebraic Numbers." In Springer Collected Works in Mathematics, 69–92. New York, NY: Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4614-8710-4_5.

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Lang, S., and H. Trotter. "Addendum to “Continued fractions of some algebraic numbers”." In Collected Papers Volume II, 111–12. New York, NY: Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4612-2120-3_8.

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Eckmann, Beno. "Simple Homotopy Type and Categories of Fractions." In Springer Collected Works in Mathematics, 576–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-37339-8_44.

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Lang, Serge, and Hale Trotter. "Addendum to “Continued Fractions of Some Algebraic Numbers”." In Springer Collected Works in Mathematics, 111–12. New York, NY: Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4614-8710-4_8.

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Van Assche, Walter. "The Impact of Stieltjes’ Work on Continued Fractions and Orthogonal Polynomials." In Œuvres Complètes Collected Papers, 5–37. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-61229-9_2.

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Dotson, Aaron D., Paul Westerhoff, and Amlan Ghosh. "DBP Reactivity of Organic Matter Fractions Collected During Extreme Weather Events." In ACS Symposium Series, 257–80. Washington, DC: American Chemical Society, 2014. http://dx.doi.org/10.1021/bk-2014-1160.ch013.

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Lin, Jennifer Shu-Jen. "Inventory Model with Fractional Brownian Motion Demand." In Computational Collective Intelligence. Technologies and Applications, 252–59. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-16693-8_27.

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Conference papers on the topic "Collecte de fraction"

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Chockalingam, Prathap, Flavio Cesar Cunha Galeazzo, Plamen Kasabov, Peter Habisreuther, Nikolaos Zarzalis, Christian Beck, Werner Krebs, and Bernhard Wegner. "Analysis of NOX Formation in an Axially Staged Combustion System at Elevated Pressure Conditions." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45239.

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The objective of this investigation was to study the effect of axially staged injection of methane in the vitiated air cross flow in a two stage combustion chamber on the formation of NOX for different momentum flux ratios. The primary cylindrical combustor equipped with a low swirl air blast nozzle operating with Jet-A liquid fuel generates vitiated air in the temperature range of 1473–1673 K at pressures of 5–8 bar. A methane injector was flush mounted to the inner surface of the secondary combustor at an angle of 30°. Oil cooled movable and static gas probes were used to collect the gas samples. The mole fractions of NO, NO2, CO, CO2 and O2 in the collected exhaust gas samples were measured using gas analyzers. For all the investigated operating conditions, the change in the mole fraction of NOX due to the injection of methane (ΔNOX) corrected to 15% O2 and measured in dry mode was less than 15 ppm. The mole fraction of ΔNOX increased with an increase in mass flow rate of methane and it was not affected by a change in the momentum flux ratio. The penetration depth of the methane jet was estimated from the profiles of mole fraction of O2 obtained from the samples collected using the movable gas probe. For the investigated momentum flux ratios, the penetration depth observed was 15 mm at 5 bar and 5 mm at 6.5 and 8 bar. The results obtained from the simulations of the secondary combustor using a RANS turbulence model were also presented. Reaction modeling of the jet flame present in a vitiated air cross flow posed a significant challenge as it was embedded in a high turbulent flow and burns in partial premixed mode. The applicability of two different reaction models has been investigated. The first approach employed a combination of the eddy dissipation and the finite rate chemistry models to determine the reaction rate, while the presumed JPDF model was used in the further investigations. Predictions were in closer agreement to the measurements while employing the presumed JPDF model; this model was also able to predict some key features of the flow as the change of penetration depth with the pressure.
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Bernardo, Luís Ricardo, Henrik Davidsson, and Björn Karlsson. "Evaluation of a High Solar Fraction Collector System." In EuroSun 2010. Freiburg, Germany: International Solar Energy Society, 2010. http://dx.doi.org/10.18086/eurosun.2010.09.04.

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Hage, Ilige S., and Ramsey F. Hamade. "Distribution of Porosity in Cortical (Bovine) Bone." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51703.

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Pores (namely lacunae, clusters of canaliculi, Haversian canals, and resorption cavities) are present throughout cortical bone. This paper characterizes the area fraction (AF, %)) of each type of these pores as function of distance from the bone’s geometric center while noting the region in which such pores are located: midcortical or periosteal. Optical slides (at 20X) are taken from 2 cortical bone biopsies named bone 1 and bone 2 and cut at mid-diaphysis femur from 2 different (about 2 year-old) bovine cows. The slides are collected from posterior (pericortical) and anterior (intracortical) locations. The area of each of these biopsies is about 2.5mm × 3mm located near the outer cortex of the bone. In polar coordinates from the bone’s center, the areas cover radial distance of about 3.3 mm (of radius, R) and encompass an arc of 10°. Automated segmentation is used to locate and identify all pores in the optical slides the shapes of which are best fitted into ellipses. Values of area fraction, AF (%) of said fitted ellipses are then automatically calculated in secondary osteons for both regions. Variations in values of area fraction AF (%) are related to actual areas of pores (based on their defining equations). Observations suggest that area fractions (%) of all pores (but to lesser degree for Haversian canals), to significantly decrease linearly and in a steep fashion with R (statistically significant, p < 0.01) in the anterior region where osteonal growth is expected to have continued to develop. However, in the posterior region where osteonal growth appears to have matured, area fraction (%) values seem to have reached a steady state resulting in fairly flat behavior versus R. All observations are equally applicable for biopsies collected from bone 1 and bone 2.
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Hotz, Nico. "Micro- and Nano-Structured Catalytic Reactor for Biofuel Reforming in a Solar Collector." In ASME 2012 6th International Conference on Energy Sustainability collocated with the ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/es2012-91338.

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In this study, a novel flow-based method is presented to place catalytic nanoparticles into a reactor by solgelation of a porous ceramic consisting of copper-based nanoparticles, silica sand, ceramic binder, and a gelation agent. This method allows for the placement of a liquid precursor containing the catalyst into the final reactor geometry without the need of impregnating or coating of a substrate with the catalytic material. The so generated foam-like porous ceramic shows properties highly appropriate for use as catalytic reactor material, e.g., reasonable pressure drop due to its porosity, high thermal and catalytic stability, and excellent catalytic behavior. The catalytic activity of micro-reactors containing this foam-like ceramic is tested in terms of their ability to convert alcoholic biofuel (e.g. methanol) to a hydrogen-rich gas mixture with low concentrations of carbon monoxide (up to 75% hydrogen content and less than 0.2% CO, for the case of methanol). This gas mixture is subsequently used in a low-temperature fuel cell, converting the hydrogen directly to electricity. A low concentration of CO is crucial to avoid poisoning of the fuel cell catalyst. Since conventional Polymer Electrolyte Membrane (PEM) fuel cells require CO concentrations far below 100 ppm and since most methods to reduce the mole fraction of CO (such as Preferential Oxidation or PROX) have CO conversions of up to 99%, the alcohol fuel reformer has to achieve initial CO mole fractions significantly below 1%. The catalyst and the porous ceramic reactor of the present study can successfully fulfill this requirement. The results of the present study confirm that product gas mixtures with up to 75% hydrogen content and less than 0.2% CO content can be achieved, which is an excellent result. The reactor temperature can be kept as low as 220°C while obtaining a methanol conversion of up to 70%. The used PROX catalyst showed selective CO conversion rates above 99.5% for temperatures between 80 and 100°C in presence of large molar fractions of H2O and CO2.
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Oloyede, Olamilekan R., Tim Bigg, and Andrew M. Mullis. "Effect of Cooling Rate on Drop-Tube Processed Commercial Grey Cast Iron." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-52368.

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This study focuses on the fundamental of solidification of commercial grey cast iron as a function of the externally applied cooling rate. Grey cast iron powders were prepared using the drop-tube method, which is a good analogue for commercial production via high pressure gas atomization. The as-solidified droplets were collected and sieved into size ranges from > 850 μm to < 53 μm diameter, with estimated cooling rates of 500 K s−1 to 75,000 K s−1, with each sieve fraction being prepared for metallographic characterization. The microstructure and phase composition of the powders were analyzed using XRD, optical and scanning electron microscopy, with the results being compared against a control sample subject to slow cooling in the drop-tube crucible; which has typical grey cast iron microstructure with extensive flake graphite in a largely ferrite matrix. In contrast, flake graphite was absent in virtually all the drop-tube samples, even in those with the most modest cooling rates. Microstructural analysis revealed that as the cooling rate increased there was less fragmentation of the primary austenite/ferrite dendrites and the volume fraction of primary dendritic material increased. Hence, as the particle fractions get smaller (D < 106 μm) there is a distinct microstructural evidence of a martensite phase which is related to its better mechanical properties (microhardness) as the sample sizes decrease.
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Lessard, Étienne, and Jun Yang. "Void Fraction Measurements for Air-Water Pipe Flows Using Quick-Closing Valves and Wire-Mesh Sensors." In ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/fedsm2018-83405.

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In support of a header/feeder phenomena study, an adiabatic, near-atmospheric, air-water flow loop was commissioned simulating a single feeder of a Pressurized Heavy Water Reactor’s primary heat transport system under a postulated Loss of Coolant Accident scenario. An extensive database in representative two-phase flow conditions was collected, 750 tests in total, in order to create a two-phase flow map to be used in the more complex geometries such as header/feeder systems. The flow loop consists of two vertical test sections, for upwards and downwards flow, and one horizontal test section, each with an inner diameter of 32 mm and at least 120 diameters in length. Superficial velocities extended up to 6 m/s for the water and 10 m/s for the air. Void fraction was measured by means of quick-closing valves and a pair of wire-mesh sensors (WMS) in each test section. Two-phase repeatability tests showed that the liquid and gas superficial velocities varied by 1.1% and 0.6% at reference conditions of 2.0 and 2.8 m/s, respectively. The corresponding void fraction measurements varied for the quick-closing valves by at most 6.8%, which indicates a low sensitivity to the closure time of the valves and an appropriate axial distance between them, and 2.3% for the WMS. For both measurement techniques, the largest variations occurred in the vertical downwards test section. For the formal two-phase tests, over 600 distinct flow conditions were performed. The results showed that the two measurement techniques agreed within 5% at high void fractions and low liquid flow rates in vertical flow. For all other cases corresponding to the transitional or dispersed bubbly flow regime, the WMS over-estimated the void fraction by a consistent bias. An empirical correction is proposed, with a root-mean-square error of 6.6% across all tests. The void fraction map resulting from this database provides validation for the WMS measurements, a quantitative assessment of its uncertainty and range of applicability, and will be used as a reference in future tests under similar scale and flow conditions.
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Tokuyama, M. "Universal Features of Collective Interactions in Hard-Sphere Systems at Higher Volume Fractions." In SLOW DYNAMICS IN COMPLEX SYSTEMS: 3rd International Symposium on Slow Dynamics in Complex Systems. AIP, 2004. http://dx.doi.org/10.1063/1.1764053.

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Hewlin, Rodward L., and John P. Kizito. "Development of a Capacitance Based Void Fraction Sensor for Two-Phase Flow Measurements." In ASME 2013 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/fedsm2013-16256.

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The aim of this paper was to develop a capacitance based sensor capable of measuring void fraction in a continuous two-phase flow field. The design methodology and operation of the capacitance based void fraction sensor is discussed. Two designs of capacitance void fraction sensors were developed and tested. Some of the problems associated with the first were identified and a new sensor electrode configuration was developed which presented a more sensitive and repeatable response. Data was collected covering a wide range of void fraction measurements ranging from 0 to 1 for water as the working fluid. Calibration of the sensor required that the air gap or void capacitance (dry signal) be measured followed by an increase in liquid levels (wet signal) to obtain a range of void fraction measurements for static calibration. The static calibration data obtained was nonlinear for the full range of void fraction measurements for water. This paper covers the design requirements, calibration procedure and static calibration data obtained for the developed sensor, and dynamic void fraction data measurements. The sensor was tested in both a horizontal and vertical orientation and proved to be orientation insensitive. The experimental results are promising for water and verify successful operation for measuring void fraction in continuous two-phase flows.
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Zeng, Caibin, YangQuan Chen, and Igor Podlubny. "Is Our Universe Accelerating Dynamics Fractional Order?" In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-46216.

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In this paper, a fractional dynamics approach is used to characterize the observed accelerating expansion of the universe. We claim that the evolution of accelerating expansion obeys an α-exponential function, which is the fundamental solution of linear fractional order dynamical equation. We find that the Hubble constant is 67.8807, 68.2546, and 67.9119 for all redshift z < 1.5, z < 1, and z < 0.1 based on the dataset collected by the Supernova Cosmology Project. Furthermore, we verify that the expansion rate of our universe is speeding up and actually obeys a Mittag-Leffler law.
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Cooper, Thomas A., and James S. Wallace. "Design of a 200 kWe Solar Thermal Power Plant for Ontario." In ASME 2008 2nd International Conference on Energy Sustainability collocated with the Heat Transfer, Fluids Engineering, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/es2008-54216.

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A preliminary design and feasibility study has been conducted for a 200 kWe solar thermal power plant for operation in Ontario. The objective of this study is to assess the feasibility of small-scale commercial solar thermal power production in areas of relatively low insolation. The design has been developed for a convention centre site in Toronto, Ontario. The plant utilizes a portion of the large flat roof area of the convention centre to accommodate the collector array. Each power plant module provides a constant electrical output of 200 kWe throughout the year. The system is capable of maintaining the constant output during periods of low insolation, including night-time hours and cloudy periods, through a combination of thermal storage and a supplemental natural gas heat source. The powerplant utilized the organic Ranking cycle (ORC) to allow for relatively low source temperatures from the solar collector array. A computer simulation model was developed to determine the performance of the system year-round using the utilizability-solar fraction method. The ORC powerplant uses R245fa as the working fluid and operates at an overall efficiency of 11.1%. The collector is a non-concentrating evacuated tube type and operates at a temperature of 90°C with an average annual efficiency of 23.9%. The system is capable of achieving annual solar fractions of 0.686 to 0.874 with collector array areas ranging from 30 000 to 40 000 m2 and storage tank sizes ranging from 3.8 to 10 × 106L respectively. The lowest possible cost of producing electricity from the system is $0.393 CAD/kWh. The results of the study suggest that small-scale solar thermal plants are physically viable for year round operation in Ontario. The proposed system may be economically feasible given Ontario’s fixed purchase price of $0.42 CAD/kWh, but the cost of producing electricity from the system is highly dependent on the price of the solar collector.
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Reports on the topic "Collecte de fraction"

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Knight, R. D., and P. J. Henderson. Characterization of smelter dust from the mineral fraction of humus collected around Rouyn-Noranda, Quebec. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2005. http://dx.doi.org/10.4095/221133.

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Thurston, Alison, Zoe Courville, Lauren Farnsworth, Ross Lieblappen, Shelby Rosten, John Fegyveresi, Stacy Doherty, Robert Jones, and Robyn Barbato. Microscale dynamics between dust and microorganisms in alpine snowpack. Engineer Research and Development Center (U.S.), March 2021. http://dx.doi.org/10.21079/11681/40079.

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Dust particles carry microbial and chemical signatures from source regions to deposition regions. Dust and its occupying microorganisms are incorporated into, and can alter, snowpack physical properties including snow structure and resultant radiative and mechanical properties that in turn affect larger-scale properties, including surrounding hydrology and maneuverability. Microorganisms attached to deposited dust maintain genetic evidence of source substrates and can be potentially used as bio-sensors. The objective of this study was to investigate the impact of dust-associated microbial deposition on snowpack and microstructure. As part of this effort, we characterized the microbial communities deposited through dust transport, examined dust provenance, and identified the microscale location and fate of dust within a changing snow matrix. We found dust characteristics varied with deposition event and that dust particles were generally embedded in the snow grains, with a small fraction of the dust particles residing on the exterior of the snow matrix. Dust deposition appears to retard expected late season snow grain growth. Both bacteria and fungi were identified in the collected snow samples.
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Melanie, Haupt, and Hellweg Stefanie. Synthesis of the NRP 70 joint project “Waste management to support the energy turnaround (wastEturn)”. Swiss National Science Foundation (SNSF), January 2020. http://dx.doi.org/10.46446/publication_nrp70_nrp71.2020.2.en.

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A great deal of energy can be sourced both directly and indirectly from waste. For example, municipal waste with an energy content of around 60 petajoules is incinerated in Switzerland every year. The energy recovered directly from this waste covers around 4 % of the Swiss energy demand. However, the greatest potential offered by waste management lies in the recovery of secondary raw materials during the recycling process, thus indirectly avoiding the energy-intensive production of primary raw materials. In order to optimise the contribution to the energy turnaround made by waste management, as a first step, improvements need to be made with respect to the transparent documentation of material and cash flows, in particular. On the basis of this, prioritisation according to the energy efficiency of various recycling and disposal channels is required. Paper and cardboard as well as plastic have been identified as the waste fractions with the greatest potential for improvement. In the case of paper and cardboard, the large quantities involved result in considerable impact. With the exception of PET drinks bottles, plastic waste is often not separately collected and therefore offers substantial improvement potential. Significant optimisation potential has also been identified with regard to the energy efficiency of incineration plants. To allow municipal solid waste incineration (MSWI) plants to use the heat they generate more effectively, however, consumers of the recovered steam and heat need to be located close by. A decisive success factor when transitioning towards an energy-efficient waste management system will be the cooperation between the many stakeholders of the federally organised sector. On the one hand, the sector needs to be increasingly organised along the value chains. On the other hand, however, there is also a need to utilise the freedom that comes with federal diversity in order to test different solutions.
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