Journal articles: 'Wide fraction'

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Kouwenhoven, M. B. N., S. P. Goodwin, Richard J. Parker, M. B. Davies, D. Malmberg, and P. Kroupa. "The origin of very wide binary systems." Proceedings of the International Astronomical Union 5, S266 (August 2009): 438–41. http://dx.doi.org/10.1017/s1743921309991633.

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AbstractThe majority of stars in the Galactic field and halo are part of binary or multiple systems. A significant fraction of these systems have orbital separations in excess of thousands of astronomical units, and systems wider than a parsec have been identified in the Galactic halo. These binary systems cannot have formed through the ‘normal’ star-formation process, nor by capture processes in the Galactic field. We propose that these wide systems were formed during the dissolution phase of young star clusters. We test this hypothesis using N-body simulations of evolving star clusters and find wide binary fractions of 1–30%, depending on initial conditions. Moreover, given that most stars form as part of a binary system, our theory predicts that a large fraction of the known wide ‘binaries’ are, in fact, multiple systems.

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Sidji, Iriani. "Penggunaan Gambar Luas Daerah Untuk Meningkatkan Pemahaman Siswa Terhadap Operasi Penjumlahan Bilangan Pecahan SD Kabupaten Bone." JIKAP PGSD: Jurnal Ilmiah Ilmu Kependidikan 2, no. 1 (September 29, 2017): 162. http://dx.doi.org/10.26858/jkp.v1i2.5318.

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The purpose of this research is to increase the understanding in summing the fractions by using the wide picture of the fourth grade student area of SD Negeri 9 Ta '. Types of action research with cycles include planning, execution, observation, and reflection. Research data is activity data and student learning result in addition of fraction. Data obtained by observation, test, field notes. The result of this research is in cycle I (1) study at the stage of percentage in mempragakan image area not maximal yet (2) students have difficulties in adding fraction (3) group work not yet maximal, meanwhile in cycle II has significant increase that is (1 ) presentation at the presentation stage of the picture of the width of the area has been maximally run in accordance with the plan (2) the students are happy to do the sum of the fractions by using the broad area picture (3) the students can present the rare of fractional disappearance using the area wide image, can be seen in cycle I less qualification (K), cycle II qualification good (B). Means by using the image area in the fractional learning can improve student learning outcomes fourth grade SD Negeri 9 Ta '.

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Wang, Xiaoting, Wenfu Yan, and Mingdong Zheng. "Theoretical Extraction of Wide-Fraction Plates from Tar Distillation." Advanced Science, Engineering and Medicine 5, no. 11 (November 1, 2013): 1225–29. http://dx.doi.org/10.1166/asem.2013.1420.

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Gori, Riccardo, Francesca Giaccherini, Lu-Man Jiang, Reza Sobhani, and Diego Rosso. "Role of primary sedimentation on plant-wide energy recovery and carbon footprint." Water Science and Technology 68, no. 4 (August 1, 2013): 870–78. http://dx.doi.org/10.2166/wst.2013.270.

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The goal of this paper is to show the effect of primary sedimentation on the chemical oxygen demand (COD) and solids fractionation and consequently on the carbonaceous and energy footprints of wastewater treatment processes. Using a simple rational procedure for COD and solids fraction quantification, we quantify the effects of varying fractions on CO2 and CO2-equivalent mass flows, process energy demand and energy recovery. Then we analysed two treatment plants with similar biological nutrient removal processes in two different climatic regions and quantified the net benefit of gravity separation before biological treatment. In the cases analysed, primary settling increases the solid fraction of COD that is processed in anaerobic digestion, with an associated increase in biogas production and energy recovery, and a reduction in overall emissions of CO2 and CO2-equivalent from power importation.

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Deacon, N. R., and A. L. Kraus. "Wide binaries are rare in open clusters." Monthly Notices of the Royal Astronomical Society 496, no. 4 (June 30, 2020): 5176–200. http://dx.doi.org/10.1093/mnras/staa1877.

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ABSTRACT The population statistics of binary stars are an important output of star formation models. However, populations of wide binaries evolve over time due to interactions within a system’s birth environment and the unfolding of wide, hierarchical triple systems. Hence, the wide binary populations observed in star-forming regions or OB associations may not accurately reflect the wide binary populations that will eventually reach the field. We use Gaia DR2 data to select members of three open clusters, Alpha Per, the Pleiades, and Praesepe and to flag cluster members that are likely unresolved binaries due to overluminosity or elevated astrometric noise. We then identify the resolved wide binary population in each cluster, separating it from coincident pairings of unrelated cluster members. We find that these clusters have an average wide binary fraction in the 300–3000 au projected separation range of 2.1$\pm ^{0.4}_{0.2}$ per cent increasing to 3.0$\pm ^{0.8}_{0.7}$ per cent for primaries with masses in the 0.5–1.5 M⊙ range. This is significantly below the observed field wide binary fraction, but shows some wide binaries survive in these dynamically highly processed environments. We compare our results with another open cluster (the Hyades) and two populations of young stars that likely originated in looser associations (young moving groups and the Pisces-Eridanus stream). We find that the Hyades also has a deficit of wide binaries while the products of looser associations have wide binary fractions at or above field level.

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Brosche, P., and D. Sinachopoulos. "The optical fraction of a hipparcos sample of wide binaries." Astrophysics and Space Science 142, no. 1-2 (March 1988): 255–58. http://dx.doi.org/10.1007/bf00656218.

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Tweedie, S., J. Charlton, V. Clark, and A. Bird. "Methylation of genomes and genes at the invertebrate-vertebrate boundary." Molecular and Cellular Biology 17, no. 3 (March 1997): 1469–75. http://dx.doi.org/10.1128/mcb.17.3.1469.

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Patterns of DNA methylation in animal genomes are known to vary from an apparent absence of modified bases, via methylation of a minor fraction of the genome, to genome-wide methylation. Representative genomes from 10 invertebrate phyla comprise predominantly nonmethylated DNA and (usually but not always) a minor fraction of methylated DNA. In contrast, all 27 vertebrate genomes that have been examined display genome-wide methylation. Our studies of chordate genomes suggest that the transition from fractional to global methylation occurred close to the origin of vertebrates, as amphioxus has a typically invertebrate methylation pattern whereas primitive vertebrates (hagfish and lamprey) have patterns that are typical of vertebrates. Surprisingly, methylation of genes preceded this transition, as many invertebrate genes have turned out to be heavily methylated. Methylation does not preferentially affect genes whose expression is highly regulated, as several housekeeping genes are found in the heavily methylated fraction whereas several genes expressed in a tissue-specific manner are in the nonmethylated fraction.

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Bozorova, D. T., Sh P. Gofurov, A. M. Kokhkharov, and O. B. Ismailova. "STUDY OF HETEROMOLECULAR INTERACTION OF NONAQUEOUS BINARY SOLUTIONS." «Узбекский физический журнал» 22, no. 2 (January 3, 2020): 111–14. http://dx.doi.org/10.52304/.v22i2.187.

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In this work, the refractometry method was used to study of the molecular interactions and structural characteristics of dimethylformamide-ethanol and cyclohexane-ethanol binary mixtures. The refractive indices of mixtures were measured over a wide range of dimethylformamide and cyclohexane concentrations (0−1.0 mole fractions) at 25°С. It has been shown that heteromolecular complexes in binary solutions are formed at the concentration of ∼0.5 mole fraction of those compounds due to strong H-bonds. Relatively weak interactions are determined at a concentration of ∼0.2 and ∼0.9 mole fraction of dimethylformamide and ∼0.2 and ∼0.8 mole fraction of cyclohexane.

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Zainon, Mohd Zamri, Mohd Ardan Zubir, and Rahizar Ramli. "Velocities Effects on the Void Fraction Distribution in a Vertical Gas-Liquid Two-Phase Flow Channel." Advanced Materials Research 889-890 (February 2014): 369–73. http://dx.doi.org/10.4028/www.scientific.net/amr.889-890.369.

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Measurement of void fraction in a vertically arranged gas-liquid two-phase flow channel has been conducted for wide range of flow conditions using a specially developed sensor based on electric conductance method. The effects of velocities of both phases were examined with variety of combinations using an industrial scale two-phase flow loop. The results show that at a constant rate of liquid superficial velocities the void fractions increases with the increasing gas superficial velocities and at higher velocities of liquid phase, the value of void fraction becoming lower. The average void fractions were also compared with other scholars results.

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Hwang, Hsiang-Chih, Jacob H. Hamer, Nadia L. Zakamska, and Kevin C. Schlaufman. "Very wide companion fraction from Gaia DR2: A weak or no enhancement for hot Jupiter hosts, and a strong enhancement for contact binaries." Monthly Notices of the Royal Astronomical Society 497, no. 2 (July 20, 2020): 2250–59. http://dx.doi.org/10.1093/mnras/staa2124.

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ABSTRACT There is an ongoing debate on whether hot Jupiter hosts are more likely to be found in wide binaries with separations of ≳100 AU. In this paper, we search for comoving, very wide companions with separations of 103–104 AU for hot Jupiter hosts and main-sequence contact binaries in Gaia DR2, and compare the very wide companion fractions with their object-by-object-matched field star samples. We find that 11.9 ± 2.5 per cent of hot Jupiter hosts and 14.1 ± 1.0 per cent of contact binaries have companions at separations of 103–104 AU. While the very wide companion fraction of hot Jupiter hosts is a factor of 1.9 ± 0.5 larger than their matched field star sample, it is consistent, within ∼1σ, with that of matched field stars if the matching is only with field stars without close companions (within ∼50 AU) as is the case for hot Jupiter hosts. The very wide companion fraction of contact binaries is a factor of 3.1 ± 0.5 larger than their matched field star sample, suggesting that the formation and evolution of contact binaries are either tied to or correlated with the presence of wide companions. In contrast, the weak enhancement of very wide companion fraction for hot Jupiter hosts implies that the formation of hot Jupiters is not as sensitive to those environment properties. Our results also hint that the occurrence rates of dual hot Jupiter hosts and dual contact binaries may be higher than the expected values from random pairing of field stars, which may be due to their underlying metallicity and age dependence.

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Elnour, Ahmed Adam M., Mohamed Elwathig Saeed Mirghani, Nassereldeen A. Kabbashi, Md Zahangir Alam, and Khalid Hamid Musa. "Active Fractions of Methanol Crude Obtained from Acacia seyal gum: Antioxidant Capacity, using FTIR Analysis." Borneo Journal of Pharmacy 2, no. 2 (November 14, 2019): 94–107. http://dx.doi.org/10.33084/bjop.v2i2.915.

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The present study is on Acacia seyal gum (ASG), which is an exudate from Talha tree. It provides a rich source of polyphenolics compounds that are used traditionally in folk medicine. The study aims to determine the antioxidant capacity (AC) and functional groups of ASG and Prebio-T-commercial (PTC) samples. The methanol crude extracts of both ASG and PTC have fractioned into chloroform (CHF), hexane (HF), acetone (AF) and methanol (MF) using solvent-solvent portion. Both ferric reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC) assays for each fraction examined. Crude methanol extracts (CME) and its active compositions also analysed carefully using Fourier Transform Infrared Spectroscopy (FTIR) technique. The findings presented a wide variety of functional groups provided by the FTIR spectra (eights bands approximately. Regarding cupric reducing antioxidant capacity (CUPRAC), the methanol crude extracts values are 888.6�4.57 mg TE/100g extract, for PTC as compared to 474.3� 2.23 mg TE/100g of extract for ASG. However, both methanol and acetone fractions revealed significantly (p = 0.05) high FRAP values ranged between 599.8�7.5 and 741.8�5.8 mg TE/100g fraction; for PTC and ASG, respectively. While CUPRAC showed insignificant (p = 0.05) same values 356.1�2.62 mg TE/100g of fraction; for MF of both PTC and ASG respectively. Therefore, in this study, methanolic fractions (MFs) are found to be more effective than acetone fractions (AFs), except for CHF and HF. Finally, the antioxidant activity of the active fraction has provided some evidence regarding its functional groups which may have used in traditional medicine.

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Wang, Bin, Yuangui Zhou, Jianyi Xue, and Delan Zhu. "Active Sliding Mode for Synchronization of a Wide Class of Four-Dimensional Fractional-Order Chaotic Systems." ISRN Applied Mathematics 2014 (March 19, 2014): 1–11. http://dx.doi.org/10.1155/2014/472371.

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We focus on the synchronization of a wide class of four-dimensional (4-D) chaotic systems. Firstly, based on the stability theory in fractional-order calculus and sliding mode control, a new method is derived to make the synchronization of a wide class of fractional-order chaotic systems. Furthermore, the method guarantees the synchronization between an integer-order system and a fraction-order system and the synchronization between two fractional-order chaotic systems with different orders. Finally, three examples are presented to illustrate the effectiveness of the proposed scheme and simulation results are given to demonstrate the effectiveness of the proposed method.

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OSAKABE, Masahiro, and Natuko IKEDA. "Condensation Heat Transfer in Wide Range of Non-condensing Gas Fraction." Transactions of the Japan Society of Mechanical Engineers Series B 69, no. 685 (2003): 2107–13. http://dx.doi.org/10.1299/kikaib.69.2107.

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Rasmussen, J. B. "Patterns in the Size Structure of Littoral Zone Macroinvertebrate Communities." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 10 (October 1, 1993): 2192–207. http://dx.doi.org/10.1139/f93-246.

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A wide range of size spectra was encountered in 11 lakes of the Quebec Eastern Townships; most were bimodal with maximum biomass represented between 1 and 4 mg (wet weight) and between 64 and 256 mg and minimum biomass between 8 and 32 mg. PCA was used to show that the two size modes represented independent size fractions and that they were related to different environmental factors. The biomass of the small size fraction increased strongly with submerged macrophyte biomass and with lake trophic status. The biomass of the large size fraction was independent of the small size fraction and increased with wave exposure at the site. As the macrophyte biomass increased, more of the invertebrates were found upon the plants, and the small size fraction became more dominant. This is probably a result of the animals upon the vegetation being more exposed to fish predators than those hidden within the substrate. Linear regression models are developed to predict the biomass of both size fractions as well as the slope and intercept parameters of the normalized size distribution (NSD). The size-fraction approach (using PCA) complements the simpler NSD approach; it detects functionally independent size fractions in the community that NSD parameters cannot reveal.

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Fletcher, W. K., M. Church, and J. Wolcott. "Fluvial-transport equivalence of heavy minerals in the sand size range." Canadian Journal of Earth Sciences 29, no. 9 (September 1, 1992): 2017–21. http://dx.doi.org/10.1139/e92-158.

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Sediments caught in two pit traps installed in Harris Creek, a small gravel-bed stream in southern British Columbia, were sieved to give five size fractions between 53 and 425 μm, which were then separated into their magnetic and nonmagnetic components. Estimates of transport-equivalent sizes of the higher density magnetic fractions were obtained by determining the grain sizes of magnetic and nonmagnetic particles that enter the traps at proportionally similar rates for a wide range of discharge conditions. The estimates of transport-equivalent sizes are compared with settling-velocity equivalents from settling-tube data. Each heavy-mineral size fraction is transported at a rate similar to a specific larger size fraction, which is approximated by the equivalent settling diameter of particles of lower density.

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Li, Xiaoxiao, Shaojie Song, Wei Zhou, Jiming Hao, Douglas R. Worsnop, and Jingkun Jiang. "Interactions between aerosol organic components and liquid water content during haze episodes in Beijing." Atmospheric Chemistry and Physics 19, no. 19 (October 1, 2019): 12163–74. http://dx.doi.org/10.5194/acp-19-12163-2019.

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Abstract. Aerosol liquid water (ALW) is ubiquitous in ambient aerosol and plays an important role in the formation of both aerosol organics and inorganics. To investigate the interactions between ALW and aerosol organics during haze formation and evolution, ALW was modelled based on long-term measurement of submicron aerosol composition in different seasons in Beijing. ALW contributed by aerosol inorganics (ALWinorg) was modelled by ISORROPIA II, and ALW contributed by organics (ALWorg) was estimated with κ-Köhler theory, where the real-time hygroscopicity parameter of the organics (κorg) was calculated from the real-time organic oxygen-to-carbon ratio (O∕C). Overall particle hygroscopicity (κtotal) was computed by weighting component hygroscopicity parameters based on their volume fractions in the mixture. We found that ALWorg, which is often neglected in traditional ALW modelling, contributes a significant fraction (18 %–32 %) to the total ALW in Beijing. The ALWorg fraction is largest on the cleanest days when both the organic fraction and κorg are relatively high. The large variation in O∕C, from 0.2 to 1.3, indicates the wide variety of organic components. This emphasizes the necessity of using real-time κorg, instead of fixed κorg, to calculate ALWorg in Beijing. The significant variation in κorg (calculated from O∕C), together with highly variable organic or inorganic volume fractions, leads to a wide range of κtotal (between 0.20 and 0.45), which has a great impact on water uptake. The variation in organic O∕C, or derived κorg, was found to be influenced by temperature (T), ALW, and aerosol mass concentrations, among which T and ALW both have promoting effects on O∕C. During high-ALW haze episodes, although the organic fraction decreases rapidly, O∕C and derived κorg increase with the increase in ALW, suggesting the formation of more soluble organics via heterogeneous uptake or aqueous processes. A positive feedback loop is thus formed: during high-ALW episodes, increasing κorg, together with decreasing particle organic fraction (or increasing particle inorganic fraction), increases κtotal, and thus further promotes the ability of particles to uptake water.

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Curtin, Denis, Michael H. Beare, and Weiwen Qiu. "Texture effects on carbon stabilisation and storage in New Zealand soils containing predominantly 2 : 1 clays." Soil Research 54, no. 1 (2016): 30. http://dx.doi.org/10.1071/sr14292.

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Developing strategies to sequester carbon (C) in soils requires an understanding of the key factors that influence C stabilisation. Although fine mineral particles, especially clay, play a key role in stabilising soil organic matter (SOM), the relationship between SOM and texture is often not strong. We examined the role of the fine mineral fraction in C storage in sedimentary soils in New Zealand. Soils, representing two soil Orders (Brown and Recent) and different land use histories (total of 58 soils; 0–15 cm depth) were sampled. The concentration of C (and N) in four particle size fractions (<5, 5–20, 20–50, >50 µm) was determined (soils fractionated after dispersion by sonication). The soils had a wide range of textures and SOM; the mass proportion of clay (<5 µm) ranged from 10 to 60 g 100 g–1 and soil C from 16 to 45 g kg–1. Across both soil Orders and all land uses (dairy, sheep or beef, arable and vegetable cropping), the majority of soil C (57 to 66%) was stored in the clay fraction. However, there was no correlation (R2 = 0.02; P > 0.05) between the C concentration in whole soil and clay content. The concentration of C in the clay fraction, which varied over a wide range (35 to 135 g kg–1 clay), decreased as the mass proportion of clay increased. A similar trend in C concentration was observed for the fine (5–20 µm) silt fraction. Because of this inverse relationship between the mass of the fine fractions and their C concentration, there was little change in amount of stable C (defined as C in the <20 µm fraction) as the mass proportion of fine (<20 µm) particles increased. Differences in pyrophosphate extractable aluminium explained part of the variability in C concentration in the fine fractions; however, we were unable to identify any specific physico-chemical factor that would account for the relatively low C concentrations observed in the <5 and 5–20 µm fractions of fine-textured soils. We concluded that such soils may be under-saturated and potential may exist to store additional stable C.

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Yuliani, Ratna, and Faisal Syahdeni. "Cytotoxicity of Ethanolic Extract of Papaya Leaves (Carica papaya) and its Fractions on T47D Cells." Pharmacon: Jurnal Farmasi Indonesia 17, no. 1 (June 30, 2020): 17–23. http://dx.doi.org/10.23917/pharmacon.v17i1.10760.

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Breast cancer is a cancer leading cause of high mortality rate in women. Plants produces secondary metabolites with a wide range of activity which one of the activity is anticancer. This research was conducted to investigate the cytotoxic activity of ethanolic extract of papaya leaves (Carica papaya) and its fractions on a breast cancer cell line (T47D). Extraction of the natural compounds from papaya leaves was carried out by maceration method using 96% ethanol. Fractionation of the extract was done by partition method using water, hexane and ethyl acetate to afford hexane, ethyl acetate and water fractions. The cytotoxicity of the extract and the fractions was tested using MTT assay. Chemical compounds in the ethyl acetate fraction was identified using thin layer chromatography method with silica gel GF 254 as the stationary phase and mixture of hexane and acetone with ratio of 6:4 as the mobile phase. The MTT assay results show that the extract, hexane, and water fraction with concentration of 800 mg/mL do not inhibit the growth of T47D cells whereas the growth of the cells was inhibited by the ethyl acetate fraction with IC50 value of 557.32 mg/mL. The ethyl acetate fraction contains flavonoids, alkaloids, phenolics, and terpenoids. The ethanolic extract of papaya leaves and the fractions has no potential cytotoxicity on T47D cells.

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Sharma, Ikshit, Washim Khan, Rabea Parveen, Md Javed Alam, Iftekhar Ahmad, Mohd Hafizur Rehman Ansari, and Sayeed Ahmad. "Antiurolithiasis Activity of Bioactivity Guided Fraction ofBergenia ligulataagainst Ethylene Glycol Induced Renal Calculi in Rat." BioMed Research International 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/1969525.

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Dried rhizome ofBergenia ligulata(pashanbhed) is commonly used as a traditional herbal medicine with a wide range of therapeutic applications including urolithiasis. Aqueous extract ofB. ligulatawas prepared through maceration followed by decoction (mother extract, 35.9% w/w). Further, polarity based fractions were prepared successively from mother extract which yielded 3.4, 2.9, 5.4, 7.5, and 11.3% w/w of hexane, toluene, dichloromethane (DCM),n-butanol, and water fractions, respectively. The in vitro, ex vivo, and real-time antiurolithiasis activity of mother extract and fractions were carried out using aggregation assay in synthetic urine and in rat plasma. The study revealed that DCM fraction has significantly (p<0.05) greater inhibitory potential than other fractions. Ethylene glycol in drinking water (0.75%, v/v) for 28 days was used for induction of urolithiasis and the curative effects of mother extract and DCM fraction were checked for the level of oxalate, calcium, creatinine, uric acid, and urea of both urine and serum. Treatment with mother extract and DCM fraction at a dose of 185 mg/kg and 7 mg/kg, respectively, in ethylene glycol induced rats resulted in a significant (p<0.05) decrease in serum and urine markers. Histological study revealed lower number of calcium oxalate deposits with minimum damage in the kidneys of mother extract and DCM fraction treated rats. This result provides a scientific basis for its traditional claims.

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Pedersen, Ørjan, Bjørn Ursin, and Alexey Stovas. "Wide-angle phase-slowness approximations in VTI media." GEOPHYSICS 72, no. 4 (July 2007): S177—S185. http://dx.doi.org/10.1190/1.2736350.

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An anisotropic medium with vertical symmetry axis (VTI) often presents a good model for describing real rocks. Propagation of quasi-P- and quasi-SV-waves in such media requires an expression of the vertical phase slowness, a complicated function of the horizontal phase slowness and the medium parameters. For converted-wave phase-shift migration methods, it is desired to have slowness expressions that are simple and accurate at wide angles of propagation. Taylor-series representations of the squared vertical slowness for quasi-P- and quasi-SV-waves result in new wide-angle phase-slowness approximations based on truncated series and continued-fraction representations. Slowness approximations that are exact for both vertical propagation and at a horizontal slowness corresponding to horizontally traveling qP-waves are derived. The approximation for quasi-SV-waves can be used in phase-shift migration in media where the quasi-SV wavefront contains triplications. These approximations are tested on several models and compared to previously published approximations. The numerical tests suggest that the new continued-fraction approximations are more accurate. They can be used in phase-shift migration algorithms, which are more efficient for large angles than the existing approximations.

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Sunita, P., S. Jha, S. P. Pattanayak, and S. K. Mishra. "Antimicrobial activity of Cressa cretica L., a Halophytic Plant." Journal of Scientific Research 4, no. 1 (December 26, 2011): 203. http://dx.doi.org/10.3329/jsr.v4i1.7719.

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In the present investigation different fractions (hexane, ethylacetate and methanol) of the whole methanolic extract of Cressa cretica L.(Convolulaceae), a widely grown halophytic plant were studied against wide ranges of bacteria (both positive and negative strain) and five fungi Candida albicans, Candida tropicalis – dimorphic fungi, Aspergillus fumigatus, Aspergillus niger – systemic fungi and fusarium oxysporum by agar disc diffusion method. Among the three fractions the ethylacetate fraction of C.cretica showed the highest activity, but among the pathogens highest activity was revealed against Escherichia coli, Klebsiella pneumoniae (zone of inhibition diameter in mm was found to be 26 and 31, respectively). The ethylacetate fraction was sensitive to both gram +ve and gram –ve bacterias. C.cretica showed higher inhibitory activity against the Aspergillus fumigates, Aspergillus niger (zone of inhibition diameter in mm was found to be 26 and 22, respectively) than the Candida albicans and Candida tropicalis and least was found for Fusarium oxysporum. As ethylacetate fraction revealed better activity than other fractions, further study of morphological and biochemical alterations were carried out only with ethylacetate fraction and the results revealed some morphological and biochemical alterations, which indicates that ethylacetate fraction of C. cretica possess potential broad spectrum antimicrobial activity.Keywords: Cressa cretica; Antifungal; Gram positive bacteria; Gram negative bacteria; Biochemical alterations.© 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v4i1.7719J. Sci. Res. 4 (1), 203-212 (2012)

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Safarzadeh, Mohammadtaher, Joshua D. Simon, and Abraham Loeb. "A Statistical Detection of Wide Binary Systems in the Ultrafaint Dwarf Galaxy Reticulum II." Astrophysical Journal 930, no. 1 (May 1, 2022): 54. http://dx.doi.org/10.3847/1538-4357/ac626e.

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Abstract Binary stars can inflate the observed velocity dispersion of stars in dark matter-dominated systems such as ultrafaint dwarf galaxies (UFDs). However, the population of binaries in UFDs is poorly constrained by observations, with preferred binary fractions for individual galaxies ranging from a few percent to near unity. Searching for wide binaries through nearest neighbor (NN) statistics (or the two-point correlation function) has been suggested in the literature, and we apply this method for the first time to detect wide binaries in a UFD. By analyzing the positions of stars in Reticulum II (Ret II) from Hubble Space Telescope images, we search for angularly resolved wide binaries in Ret II. We find that the distribution of their NN distances shows an enhancement at projected separations of ≲1″ relative to a model containing no binaries. We show that such an enhancement can be explained by a wide binary fraction of f b ≈ 0.007 − 0.003 + 0.008 at separations of more than 3000 au. Under the assumption that the binary separation distribution is similar to that in the Milky Way, the total binary fraction in Ret II may be on the order of 50%. We also use the observed magnitude distribution of stars in Ret II to constrain the initial mass function over the mass range 0.34–0.78 M ⊙, finding that a shallow power-law slope of 1.01 ≤ α ≤ 1.15 matches the data.

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Bao, Chong Gao, Jian Dong Xing, Yi Min Gao, and En Ze Wang. "Wear Resistant of Al₂O₃/Heat-Resistant Steel at High Temperature." Key Engineering Materials 280-283 (February 2007): 1119–22. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.1119.

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The high temperature abrasive wear resistant of the composites with different Al2O3 volume fractions, particle coating and size were investigated and the failure action of composites under different conditions at high temperature was analyzed. The results showed that the high temperature abrasive wear resistant of composite with Ni coating and wide size and 39% volume fraction of particle is the best among all composites examined.

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Romanov, Il’ya V., and Roman N. Zadorozhniy. "Isolation of fine powder faction obtained by electroerosion dispersion method." Tekhnicheskiy servis mashin, no. 3 (August 20, 2020): 119–27. http://dx.doi.org/10.22314/2618-8287-2020-58-3-119-127.

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The fundamental properties of metal powders with small particles change, which opens up a wide range of applications of such materials. Currently, nanopowders are used in many industries to improve the quality of the resulting products. (Research purpose) The research purpose is in isolating a fine fraction of metal powders obtained by electroerosive dispersion for further experiments with this material, and also proving the possibility of obtaining such fractions by this method. (Materials and methods) A fine fraction of metal powders obtained by the method of electroerosive dispersion was isolated, which proved its effectiveness in obtaining conductive powder materials with the desired final physical and mechanical properties. This method results in a fairly large spread across fractions. Authors received material for research on experimental installations of the "Nano-Center" Center for Collective Use. The article presents the methods of experimental research of fractional composition on the example of metal powders of hard alloy grades T15K6 and VK8, copper powder M1, brass powder LTs38MTsS2 and bronze powder BrAZh9-12 obtained by electroerosive dispersion. (Results and discussion) The metal powder was divided into three fractions, depending on the particle size: more than 0.071 mm, from 0.02 to 0.071 mm and less than 0.02 mm. The presence of fine particles of less than 1.5 microns in the total mass of the studied powders was proved using a membrane method with a ceramic filter. Sedimentation showed specific sizes of minimal particles (from 86.4 to 116 nm). (Conclusions) Based on the results of experiments, it is possible to obtain metal powders of a fine fraction using the method of electroerosive dispersion.

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Heck, Anisa, Stefan Nöbel, Bernd Hitzmann, and Jörg Hinrichs. "Volume Fraction Measurement of Soft (Dairy) Microgels by Standard Addition and Static Light Scattering." Food Biophysics 16, no. 2 (February 15, 2021): 237–53. http://dx.doi.org/10.1007/s11483-021-09665-z.

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AbstractThe volume fraction of the dispersed phase in concentrated soft (dairy) microgels, such as fresh cheese, is directly related to structure and rheology. Measurement or modeling of volume fraction for soft and mechanically sensitive microgel dispersions is problematic, since responsiveness and rheological changes upon mechanical input for these systems limits application of typical functional relationships, i.e., using apparent viscosity. In this paper, we propose a method to measure volume fraction for soft (dairy) microgel dispersions by standard addition and volume-weighted particle size distributions obtained by static light scattering. Relative particle volumes are converted to soft particle volume fraction, based on spiked standard particle volumes. Volume fractions for two example microgel dispersions, namely, differently produced fresh cheeses, were evaluated before and after post-treatments of tempering and mechanical processing. By selecting the size of standard particles based on size ratios and the levels of the mixing ratios/relative fractions, the method could be applied robustly within a wide range of particle sizes (1 to 500 μm) and multimodal size distributions (up to quadmodal). Tempering increased the volume fraction for both example microgel dispersions (P < 0.05). Subsequent mechanical treatment reduced the volume fraction back to the starting value before tempering (P < 0.05). Furthermore, it was shown that the increase and successive decrease in apparent viscosity with tempering and mechanical post-treatments is not exclusively due to particle aggregation and breakdown, but to volume changes of each particle. For environmentally responsive soft matter, the proposed method is promising for measurement of volume fraction.

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Farmani, Zahra, and Wolfgang Schrader. "A Detailed Look at the Saturate Fractions of Different Crude Oils Using Direct Analysis by Ultrahigh Resolution Mass Spectrometry (UHRMS)." Energies 12, no. 18 (September 7, 2019): 3455. http://dx.doi.org/10.3390/en12183455.

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SARA (Saturates, Aromatics, Resins, Asphaltenes) fractionation is a common simplification technique used for decades in petrochemical analysis. A large number of studies are dealing with the different fractions, but overall, the saturate fraction is strongly neglected. Of the very few available studies on the saturates fraction, almost all have been performed using gas chromatographic (GC) techniques. This discriminates the results of the saturate fraction especially since non-volatile, high molecular weight and polar constituents are mostly excluded. Here, for the first time, saturate fractions of different crude oils from different origins are analyzed using direct infusion ultrahigh resolution mass spectrometry (UHRMS), to study the compositions on a molecular level. Electrospray (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) are used in positive mode. The observed results show the presence of different heteroatom containing classes, with different chemical identities (i.e., presence of thiophenes, mercaptans and cyclic-sulfides in case of S-containing compounds). These results show the high affinity of some specific compounds towards different ionization techniques. Finally, the saturate fraction is shown to include much more than only volatile, saturated and aliphatic compounds. The detected compounds in this fraction present a very wide variety, not only in terms of their carbon atoms per molecule and their aromaticity, but also with regard to their functional groups and structural arrangements.

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Jeske, Agnieszka. "Mobility and distribution of barium and strontium in profiles of podzolic soils." Soil Science Annual 64, no. 1 (June 1, 2013): 2–7. http://dx.doi.org/10.2478/ssa-2013-0001.

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Abstract The study was aimed at determining the content, distribution and mobility of barium and strontium in various forest podzol soils. Samples with a wide range of chemical and physical properties were collected from typical uncontaminated soils of south-western Poland. The total metal content in the analyzed soils was considered as the geochemical background thanks to the natural features of the study site. Sequential chemical extraction procedure were used to provide information on the mobility and bioavailability of the studied metals in the soil. Fractions of Ba and Sr were determined using the five-step procedure of Tessier et al. (1979). The results show that heavy metals were generally represented by the exchangeable fraction (F1 . barium) and the residual fraction (F5 . strontium) with the average values at 53 and 69%, respectively. The mobility of barium in all soil profiles was very high, ranging within 52.54% and indicating a generally high availability and mobility. Relatively very low levels of the trace elements were found in the fraction bound to organic matter (F4: 3.8%). Very low levels of strontium were found also in the fraction bound to carbonates (F2: 2.3%). Humic-eluvial, illuvial and sideric horizons were enriched in the fractions of barium and strontium bound to iron and manganese oxides (F3).

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Shanshool, Jabir, and Emad Talib Hashim. "KINEMATIC VISCOSITY-TEMPERATURE CORRELATION FOR UNDEFINED PETROLEUM FRACTION OF A WIDE BOILING RANGE." Petroleum Science and Technology 19, no. 3-4 (March 31, 2001): 257–68. http://dx.doi.org/10.1081/lft-100000761.

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Pestryaev, E. M. "Molecular Dynamics Simulation of the Cage Effect in a Wide Packing Fraction Range." Russian Journal of Physical Chemistry A 92, no. 7 (June 8, 2018): 1321–31. http://dx.doi.org/10.1134/s0036024418070221.

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Niu, Zexi, Haibo Yuan, Song Wang, and Jifeng Liu. "Binary Fractions of G and K Dwarf Stars Based on Gaia EDR3 and LAMOST DR5: Impacts of the Chemical Abundances." Astrophysical Journal 922, no. 2 (December 1, 2021): 211. http://dx.doi.org/10.3847/1538-4357/ac2573.

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Abstract Based on the large volume Gaia Early Data Release 3 and LAMOST Data Release 5 data, we estimate the bias-corrected binary fractions of the field late G and early K dwarfs. A stellar locus outlier method is used in this work, which works well for binaries of various periods and inclination angles with single-epoch data. With a well-selected, distance-limited sample of about 90,000 GK dwarfs covering wide stellar chemical abundances, it enables us to explore the binary fraction variations with different stellar populations. The average binary fraction is 0.42 ± 0.01 for the whole sample. Thin-disk stars are found to have a binary fraction of 0.39 ± 0.02, thick-disk stars have a higher one of 0.49 ± 0.02, while inner halo stars possibly have the highest binary fraction. For both the thin- and thick-disk stars, the binary fractions decrease toward higher [Fe/H], [α/H], and [M/H] abundances. However, the suppressing impacts of [Fe/H], [α/H], and [M/H] are more significant for the thin-disk stars than those for the thick-disk stars. For a given [Fe/H], a positive correlation between [α/Fe] and the binary fraction is found for the thin-disk stars. However, this tendency disappears for the thick-disk stars. We suspect that it is likely related to the different formation histories of the thin and thick disks. Our results provide new clues for theoretical works on binary formation.

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Gera, Y., E. U. Umeh, T. A. Tor-Anyiin, and C. C. Iheukwumere. "Isolation Identification and Characterization of Diterpenes from the Stem bark of Detarium Microcarpum." NIGERIAN ANNALS OF PURE AND APPLIED SCIENCES 1 (March 13, 2019): 33–37. http://dx.doi.org/10.46912/napas.60.

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The antibacterial activity of the stem bark of Detarium microcarpum was investigated with the aim of isolating the most active ingredient. Extraction solvents used to prepare the crude extracts of the stem bark were, n-hexane, ethyl acetate, chloroform, methanol. Test bacteria included Escherichia coli, Salmonella enteriditis, Shigella dysenteriae, Staphylococcus aureus and Vibro cholerae. The extracts demonstrated a wide range of antibacterial activity on the microorganisms, with the ethyl acetate crude extract being the most active. Using liquid vacuum chromatography over silica gel, the extract was eluted with n- hexane, ethyl acetate and methanol and fifty- five fractions labeled Gl - G55 were obtained. Further antibacterial assays of the fractions led to the identification of fraction G34 as the most active fraction. This fraction was subjected to spectroscopic analysis using NMR, [(1H -1H NMR, 13C-NMR) and 2D-NMR (COSY and HMBC)]. The results showed good agreement with reported data on Copalic acid, a diterpene with chemical formula C O H O . This compound is 2 34 2 the most active ingredients of this plant and is likely to be responsible for its antibacterial activities.

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Cinar Ciftci, Goksu, Per A. Larsson, Anastasia V. Riazanova, Hans Henrik Øvrebø, Lars Wågberg, and Lars A. Berglund. "Tailoring of rheological properties and structural polydispersity effects in microfibrillated cellulose suspensions." Cellulose 27, no. 16 (September 16, 2020): 9227–41. http://dx.doi.org/10.1007/s10570-020-03438-6.

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Abstract Industrial production of low-charge microfibrillated cellulose (MFC) typically results in wide fibril size distributions. This polydispersity influences viscosity, overall colloidal stability, and rheological properties of MFC suspensions and gels in aqueous systems. In this work, a systematic rheological analysis is performed for industrially prepared MFC and fractions of different size distributions. Gel formation and flow characteristics (e.g., shear-thinning) of each fraction are examined under neutral and acidic conditions and compared with the unfractionated MFC suspension. The effects of size, aspect ratio, and surface charge on the rheology of semi-dilute MFC suspensions are discussed. The results demonstrate that particle size and aspect ratio distribution control the viscoelasticity and shear-thinning properties of MFC suspensions. An increased fraction of small diameter nanofibrils, by ex situ addition of the fine particles with high aspect ratio or removal of the coarsest particles (with lower aspect ratio) by fractionation, significantly enhances the storage modulus and the yield stress of the complex mixture, compared to the properties of the coarser fractions. New insights are also reported on the tailoring of the rheology of highly polydisperse fibrillar mixtures, where the rheological contributions of each fraction are discussed. Graphic abstract

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33

Gary, J. William. "Recent results from BABAR." EPJ Web of Conferences 235 (2020): 04001. http://dx.doi.org/10.1051/epjconf/202023504001.

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The BABAR Collaboration at SLAC continues to produce a wide variety of publications on interesting and unique topics despite having ceased data-collection operations more than 10 years ago. Presented here are the results of three recent studies. The first is on the direct measurement of the B± → K± X(3872) branching fraction, allowing the first determination of the branching fractions of the exotic X(3872) charmonium state. The second is a publication on the first observation of the D0 → K−π+e+e− branching fraction. The third is on searches for lepton flavor and lepton number violating decays in D0 meson decays, resulting in improvements over existing limits by factors that vary from 20 to almost 800 depending on the D0 decay channel.

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Post, Thomas, Glenda Lappan, and Kathleen Cramer. "Research into Practice: Children's Strategies in Ordering Rational Numbers." Arithmetic Teacher 35, no. 2 (October 1987): 33–35. http://dx.doi.org/10.5951/at.35.2.0033.

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Our comments here are based on interviews from two teaching experiments with fourth and fifth-grade chil dren. The students were taught many aspects of fractions using a variety of manipulative materials including circular and rect angular piece. Cuisenaire rods number lines, and chips. Each student had his or her own materials. Each worked independently, in small groups, and as a whole cl ass, spending much time talking about and performing a wide vari ety of fraction- related tasks.

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35

Hasan, Ebtisam H., Magdy A. Helal, Mohamed A. Nour, and Khaled M. Shokry. "Characterization of Physical, Mechanical and Fire Properties of Fiber Glass Composite due to Weight Fraction." Key Engineering Materials 600 (March 2014): 547–57. http://dx.doi.org/10.4028/www.scientific.net/kem.600.547.

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Glass-fiber reinforced plastics marketed are predominately based on one type of glass-fiber but with a wide variety of fiber formats, resin types, fillers and a wide range of process techniques. These choices result in materials with a wide range of behaviors in different applications. The aim of this work is to study the effect of different weight fraction for two types of polymeric composites for construction use. The properties of the two types of composites are characterized using conventional techniques.. The study revealed that weight fraction of 30 40 % for reinforcing glass fiber/polyester composite would achieve better characteristics. The addition of short fibers to a polymeric matrix will reduce its coefficient of thermal expansion.

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36

Braselton, W. Emmett, and Malgorzata Johnson. "Thin Layer Chromatography Convulsant Screen Extended by Gas Chromatography-Mass Spectrometry." Journal of Veterinary Diagnostic Investigation 15, no. 1 (January 2003): 42–45. http://dx.doi.org/10.1177/104063870301500109.

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Acute onset convulsive disorders in the canine may result from exposure to a variety of toxicants including strychnine, insecticides, metaldehyde, zinc phosphide, methylxanthines, drugs of abuse, bromethalin, and the tremorgenic mycotoxins (roquefortine and penitrem A). Although several of the above can be identified in a single gas chromatography-mass spectrometry (GC-MS) screen most have to be determined by separate tests. This report describes a modification of the strychnine extraction procedure, which allows thin layer chromatographic (TLC) identification of strychnine, bromethalin, roquefortine, and penitrem A in suspect baits, stomach contents or vomitus, and extends the identification to a wide variety of drugs, pesticides, and environmental contaminants by GC-MS. Samples were mixed with base, extracted into CH2Cl2 and the organic fraction back-extracted with acid. The organic fraction (neutrals) was purified by gel permeation chromatography (GPC) and analyzed by TLC to determine penitrem A and bromethalin. The acidic aqueous fraction was adjusted to pH > 9 and extracted into CH2Cl2. The resulting CH2Cl2 layer (bases) was then analyzed by TLC to determine strychnine and roquefortine. The organic basic and neutral fractions were recombined with a late eluting GPC fraction and analyzed by GC-MS. Of 312 samples analyzed by TLC from 1995 to 2001, 35 were positive for strychnine alone, 58 were positive for both roquefortine and penitrem A, 4 were positive for roquefortine alone, and 1 was positive for bromethalin. None of the samples were positive for penitrem A alone. Samples negative by TLC were analyzed by the GC-MS extended procedure since mid-1999, and 14 have shown positive for a wide variety of compounds with convulsant activity.

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Kuruwita, Rajika L., Michael Ireland, Aaron Rizzuto, Joao Bento, and Christoph Federrath. "Multiplicity of disc-bearing stars in Upper Scorpius and Upper Centaurus-Lupus." Monthly Notices of the Royal Astronomical Society 480, no. 4 (August 3, 2018): 5099–112. http://dx.doi.org/10.1093/mnras/sty2108.

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ABSTRACT We present observations of disc-bearing stars in Upper Scorpius (US) and Upper Centaurus-Lupus (UCL) with moderate resolution spectroscopy in order to determine the influence of multiplicity on disc persistence after ${\sim }5\hbox{--}20\, \mathrm{Myr}$. Discs were identified using infrared (IR) excess from the Wide-field Infrared Survey Explorer (WISE) survey. Our survey consists of 55 US members and 28 UCL members, using spatial and kinematic information to assign a probability of membership. Spectra are gathered from the ANU 2.3 m telescope using the Wide Field Spectrograph (WiFeS) to detect radial velocity variations that indicate the presence of a companion. We identify two double-lined spectroscopic binaries, both of which have strong IR excess. We find the binary fraction of disc-bearing stars in US and UCL for periods up to 20 yr to be $0.06^{+0.07}_{-0.02}$ and $0.13^{+0.06}_{-0.03}$, respectively. Based on the multiplicity of field stars, we obtain an expected binary fraction of ${\sim }0.12^{+0.02}_{-0.01}$. The determined binary fractions for disc-bearing stars do not vary significantly from the field, suggesting that overall lifetime of discs may not differ between single and binary star systems.

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38

Uematsu, Yoko, Keiko Hirata, Kumi Suzuki, Kenji Iida, Teruo Kan, and Kazuo Saito. "Determination of Sucrose Esters of Fatty Acids in Food Additive Premixes by Gas Chromatography and Confirmation of Identity by Gas Chromatography/Mass Spectrometry." Journal of AOAC INTERNATIONAL 84, no. 2 (March 1, 2001): 498–506. http://dx.doi.org/10.1093/jaoac/84.2.498.

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Abstract A gas chromatographic (GC) method was developed for the determination of sucrose monoesters of fatty acids (mono-SuE) and sucrose acetate isobutyrate (SAIB) in food additive premixes. Mono-SuE and SAIB fractions were prepared by column chromatography with either a C8 or a silica gel solid-phase extraction column. The mono-SuE fraction was acetylated and applied to a wide-bore GC column (0.53 mm × 15 m) by splitless injection for determination. The SAIB fraction was applied to the GC column without derivatization. Gas chromatography/mass spectrometry was used to confirm the identity of GC peaks. The detection limits for mono-SuE and SAIB were 0.005 and 0.01%, respectively. Mono-SuE (C12, C14, C16, C18, and C18:1) and SAIB were found in commercial food additive premixes and some foods.

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39

Konopska, L. "Biochemical investigations on endosperm development in Iris pseudoacorus L." Acta Societatis Botanicorum Poloniae 41, no. 3 (2015): 369–83. http://dx.doi.org/10.5586/asbp.1972.029.

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In the successive development phases the nitrogen and protein fractions were determined and ion exchanger chromatography of globulins was performed on DEAE cellulose in the endosperm of the chalasal and micropylar poles of <i>Iris pseudoacorus</i> seeds. The phosphorus fraction were also analysed and RNA was separated by means of electrophoresis on coloured agar gel. Wide quantitative differences were found in the content of the compounds investigated between the two poles and the successive development phases.

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40

Ordabayeva, A. T., M. G. Meiramov, and A. M. Gazaliev. "Physicochemical characteristics of the wide fraction of the coal tar from ArselorMittal Temirtau, JSC." Journal of Physics: Conference Series 1611 (August 2020): 012024. http://dx.doi.org/10.1088/1742-6596/1611/1/012024.

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41

Straver, Roy, Cees B. M. Oudejans, Erik A. Sistermans, and Marcel J. T. Reinders. "Calculating the fetal fraction for noninvasive prenatal testing based on genome‐wide nucleosome profiles." Prenatal Diagnosis 36, no. 7 (May 20, 2016): 614–21. http://dx.doi.org/10.1002/pd.4816.

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42

Stolypin, V. I., A. D. Shakhov, I. A. Mnushkin, and A. E. Standrik. "Updating of installation for processing wide light hydrocarbon fraction at the Orenburg helium plant." Chemical and Petroleum Engineering 42, no. 1-2 (January 2006): 93–97. http://dx.doi.org/10.1007/s10556-006-0059-4.

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43

Lee, M., H. S. Park, J. H. Park, J. H. Oh, and M. H. Kim. "Two-phase flow pressure loss through packed particle bed for wide void fraction range." Experimental Thermal and Fluid Science 108 (November 2019): 85–94. http://dx.doi.org/10.1016/j.expthermflusci.2019.06.001.

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44

Syrpas, Michail, Kiran Subbarayadu, Vaida Kitrytė, and Petras Rimantas Venskutonis. "High-Pressure Extraction of Antioxidant-Rich Fractions from Shrubby Cinquefoil (Dasiphora fruticosa L. Rydb.) Leaves: Process Optimization and Extract Characterization." Antioxidants 9, no. 6 (May 26, 2020): 457. http://dx.doi.org/10.3390/antiox9060457.

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Dasiphora fruticosa (basionym Potentilla fruticosa) is a shrub, known in traditional medicine for centuries. Due to the wide range of pharmacological effects, interest and applications of D. fruticosa extracts are continually increasing; however, reports on optimization of extraction conditions are scarce. Herein, a multi-step high-pressure extraction process with increasing polarity solvents was developed to isolate valuable fractions from D. fruticosa leaves. Supercritical CO2 extraction recovered 2.46 g/100 g of lipophilic fraction, rich in polyunsaturated fatty acids. Further, pressurized liquid extractions (PLE) with acetone, ethanol, and water were applied to obtain antioxidant-rich higher polarity extracts. Under optimized PLE conditions, the cumulative polar fraction yield was 29.98 g/100 g. Ethanol fraction showed the highest yield (15.3 g/100 g), TPC values (148.4 mg GAE/g), ABTS•+, and DPPH• scavenging capacity (161.1 and 151.8 mg TE/g, respectively). PLE was more efficient than conventional solid–liquid extraction in terms of extraction time, extract yields, and in vitro antioxidant capacity. Phytochemical characterization of PLE extracts by UPLC-Q-TOF-MS revealed the presence of hyperoside, ellagic acid, among other health beneficial phenolic substances. Τhis study highlights the potential of high-pressure extraction techniques to isolate antioxidant-rich fractions from D. fruticosa leaves with multipurpose applications, including the prevention and treatment of chronic diseases.

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45

Jonker, Willem, Koen de Vries, Niels Althuisius, Dick van Iperen, Elwin Janssen, Rob ten Broek, Corine Houtman, et al. "Compound Identification Using Liquid Chromatography and High-Resolution Noncontact Fraction Collection with a Solenoid Valve." SLAS TECHNOLOGY: Translating Life Sciences Innovation 24, no. 6 (May 16, 2019): 543–55. http://dx.doi.org/10.1177/2472630319848768.

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We describe the development of a high-resolution, noncontact fraction collector for liquid chromatography (LC) separations, allowing high-resolution fractionation in high-density well plates. The device is based on a low-dead-volume solenoid valve operated at 1–30 Hz for accurate collection of fractions of equal volume. The solenoid valve was implemented in a modified autosampler resulting in the so-called FractioMate fractionator. The influence of the solenoid supply voltage on solvent release was determined and the effect of the frequency, flow rate, and mobile phase composition was studied. For this purpose, droplet release was visually assessed for a wide range of frequencies and flow rates, followed by quantitative evaluation of a selection of promising settings for highly accurate, repeatable, and stable fraction collection. The potential of the new fraction collector for LC-based bioactivity screening was demonstrated by fractionating the LC eluent of a mixture of estrogenic and androgenic compounds, and a surface water sample (blank and spiked with bioactives) combining mass spectrometric detection and two reporter gene assays for bioactivity detection of the fractions. Additionally, a mixture of two compounds was repeatedly LC separated and fractionated to assess the feasibility of the system for analyte isolation followed by nuclear magnetic resonance analysis.

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46

Kurnianto, Muhammad A., Harsi D. Kusumaningrum, Hanifah N. Lioe, and Ekowati Chasanah. "Partial Purification and Characterization of Bacteriocin-Like Inhibitory Substances Produced by Streptomyces sp. Isolated from the Gut of Chanos chanos." BioMed Research International 2021 (December 14, 2021): 1–12. http://dx.doi.org/10.1155/2021/7190152.

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Bacteriocin-like inhibitory substances (BLIS) have sparked great interest because of their promising use in food as natural antimicrobial agents. In this work, six Streptomyces isolates obtained from the gut of Chanos chanos demonstrated their ability to produce extracellular metabolites with inhibitory activity against Salmonella enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus. Exposure of the extracellular metabolites to proteolytic enzymes (i.e., proteinase-K, trypsin, and pepsin) revealed high sensitivity and confirmed their proteinaceous nature. The metabolites were stable at high temperatures (up to 100°C for 30 min) and a wide range of pH (pH 2.0–7.0). Fractionation of the crude BLIS by filtration yielded three fractions based on molecular weight: <3 kDa, 3–10 kDa, and >10 kDa. Analysis of the antibacterial activity of these fractions showed increased specific activity, especially in the fraction with a molecular weight (MW) of <3 kDa, relative to the crude sample. The fraction with MW < 3 kDa had minimum inhibitory and bactericidal concentrations in ranges 0.04–0.62 mg·mL−1 and 0.08–1.25 mg·mL−1, respectively. This fraction also showed better temperature and pH stability compared with crude BLIS. Brine shrimp toxicity assay revealed that this fraction has moderate toxicity with a 50% lethal concentration of 226.975 μg·mL−1 (i.e., moderate toxicity) to Artemia salina. Identification of the peptide sequences of this fraction by liquid chromatography–tandem mass spectrometry yielded 130 proteins with retention times of 15.21–19.57 min. Eleven proteins with MWs of 1345.66–2908.35 Da and composed of less than 30 amino acid residues with high hydrophobicity (15.34–26.22 kcal·mol−1) appeared to be responsible for the antibacterial activity of the fraction. This study revealed the potential application of BLIS from Streptomyces, especially BLIS SCA-8, as antibacterial agents.

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Park, Junhong, Thomas Siegmund, and Luc Mongeau. "Viscoelastic Properties of Foamed Thermoplastic Vulcanizates and their Dependence on Void Fraction." Cellular Polymers 22, no. 3 (May 2003): 137–56. http://dx.doi.org/10.1177/026248930302200301.

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Experimental techniques to measure the viscoelastic mechanical properties of foamed elastomers at high frequencies were developed and applied to study foamed thermoplastic vulcanizates. The measurements were performed for foams with a wide range of void fractions such that a transition from a true porous solid to a foam was present. The frequency and time dependence of the dynamic and relaxation moduli, respectively, were measured and were shown to depend on the loss factor of the elastomer. The measured variation of the dynamic and the relaxation moduli with the void fraction did not depend on frequency and time in the frequency and time range of interest. This suggested that the time and frequency dependence of elastic moduli was determined mostly by the void fraction and the corresponding material microstructure. Property measurement results were compared to predictions for porous solids using the Mori-Tanaka method as well as methods for cellular solids.

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48

Taylor, C. E., M. J. Pettigrew, and I. G. Currie. "Random Excitation Forces in Tube Bundles Subjected to Two-Phase Cross-Flow." Journal of Pressure Vessel Technology 118, no. 3 (August 1, 1996): 265–77. http://dx.doi.org/10.1115/1.2842189.

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Data from two experimental programs have been analyzed to determine the characteristics of the random excitation forces associated with two-phase cross-flow in tube bundles. Large-scale air-water flow loops in France and Canada were used to generate the data. Tests were carried out on cantilevered, clamped-pinned, and clamped-clamped tubes in normal-square, parallel-triangular, and normal-triangular configurations. Either strain gages or force transducers were used to measure the vibration response of a centrally located tube as the tube array was subjected to a wide range of void fractions and flow rates. Power spectra were analyzed to determine the effect of parameters such as tube diameter, frequency, flow rate, void fraction, and flow regime on the random excitation forces. Normalized expressions for the excitation force power spectra were found to be flow-regime dependent. In the churn flow regime, flow rate and void fraction had very little effect on the magnitude of the excitation forces. In the bubble-plug flow regime, the excitation forces increased rapidly with flow rate and void fraction.

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Pereira, Woodman, Brahmbhatt, and Chuck. "The Optimized Production of 5-(Hydroxymethyl)furfural and Related Products from Spent Coffee Grounds." Applied Sciences 9, no. 16 (August 15, 2019): 3369. http://dx.doi.org/10.3390/app9163369.

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The increasing consumption of coffee worldwide has led to higher amounts of spent coffee grounds (SCG) being produced which are generally disposed of in landfill or used as compost. However, the wide range of molecules present in SCG such as saccharides, lignin, lipids and proteins give this biomass source a large chemical functionality. In this work, SCG were fractionated to separate the components into three separate portions for further valorization; these were hemicellulose-enriched fractions (HEF), lignin-enriched fraction (LEF) and cellulose-enriched fraction (CEF). HEF was effectively used in the growth of the oleaginous yeast Metschnikowia pulcherrima, additionally, the C6 sugars present in this fraction suggests that it can be used in the production of 5-hydroxymethylfurfural (HMF). The LEF had a considerable high heating value (HHV) and would be suitable as a biofuel component for combustion. CEF was efficiently used in the production of HMF as 0.35 g of this product were obtained from 10 g of SCG. Such results demonstrate that SCG can be effectively used in the production of HMF within a biorefinery concept.

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Schmauder, Siegfried, Ulrich Weber, Andreas Reuschel, and Markus Willert. "Simulation of the Mechanical Behaviour of Metal Matrix Composites." Materials Science Forum 678 (February 2011): 49–60. http://dx.doi.org/10.4028/www.scientific.net/msf.678.49.

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Abstract:

A model based on the geometry of the phases is introduced in order to investigate the mechanical properties of interpenetrating microstructures. In order to characterize the elastic and elastic-plastic properties of the composite a self consistent unit cell model is applied on a wide range of volume fractions for an Al/TiO2 composite. Besides the volume fraction a microstructural based parameter is used, the matricity, to describe the mutual circumvention of both phases. Computations are carried out for different temperatures and void volume fractions. In addition a conservative fracture criterion based on critical normal stresses is applied to derive realistic stress strain curves.

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