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Chemija ◽  
2021 ◽  
Vol 32 (3-4) ◽  
Author(s):  
Indrė Vaičikauskytė ◽  
Vilius Poškus ◽  
Vytautas Nekrošius ◽  
Vida Vičkačkaitė ◽  
Aivaras Kareiva

In this study, the distillation fractions of cider brandy produced illegally in Lithuania using gas chromatographic-mass spectrometry method were investigated. The conditions of gas chromatography-mass spectrometry were firstly optimized. A qualitative analysis of three distillation fractions was performed and estimated. The first fraction (initial) of distillation products was collected for 0.5 h, the second one (intermediate) was collected for the next 1.5 h and the third (main) fraction for the next 5 h. A method of the quantitative analysis of different volatile analytes such as acetaldehyde, methanol, ethanol, 1-propanol, isobutanol, 1-butanol, isoamyl alcohol and benzyl alcohol in the distillation products was also developed. The concentration of ethanol decreased significantly in the main fraction in comparison with those of the initial and intermediate fractions. The concentration of 1-propanol, isobutanol, 1-butanol and isoamyl alcohol in the last fraction decreased drastically as well.


Author(s):  
Zamir BEPPAEV ◽  
Lidia ASTVATSATUROVA ◽  
Sergey KOLODYAZHNIY ◽  
Sergey VERNIGORA ◽  
Vladislav LOPATINSKIY

The results of the study of the grain-size composition and the grade of crushability of recycled crushed stone and their dependence on the strength of the original recycled concrete are presented. It is found that recycled crushed stone obtained from the original concrete of classes B10 - B30 does not meet the requirements of GOST 8267-93 for total residues on Ø25, Ø20, Ø5 and Ø2.5 sieves. Regardless of the strength of the original concrete, the main fraction of recycled crushed stone is grains with sizes from 12.5 to 20 mm. The strength (grade in terms of crushability) of the recycled crushed stone increases with an increase in the strength of the original concrete. The study of the main parameters of recycled crushed stone at the current moment has been carried out in an insufficient (for widespread introduction into production) volume and requires further study for the subsequent development of independent regulatory and technical documentation (or additions to the current regulatory and technical documents).


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Natalia del Carmen Espinosa-Murillo ◽  
José Armando Ulloa ◽  
Judith Esmeralda Urías-Silvas ◽  
Petra Rosas-Ulloa ◽  
José Carmen Ramírez-Ramírez ◽  
...  

Abstract A protein isolate from passion fruit seeds (PFSPI) obtained by alkaline extraction and isoelectric precipitation was treated with sonication for 15 and 30 min at 40 kHz to evaluate its impact on the physicochemical and functional properties. The PFSPI had a purity of 96.21% protein, with albumins being the main fraction (75.66%). Ultrasound increased the bulk density (ρ) of PFSPI by 13.3% and the formation a more porous structure by a greater separation between particles. Protein solubility of PFSPI in the range of pH 2–12 sonicated for 15 and 30 min, increased on average 5.21 and 9.86%, respectively, in comparison with the control. PFSPI foaming properties were influenced by pH and sonication time, achieving up to 577%, while the minimum gelling concentration was reduced from 4 to 2% at pH 7. Therefore, sonication treatment improved some functional properties of PFSPI for its potential use as a food ingredient.


Metabolites ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 326
Author(s):  
Yasmijn Balder ◽  
Alessia Vignoli ◽  
Leonardo Tenori ◽  
Claudio Luchinat ◽  
Edoardo Saccenti

In this study, we investigated blood lipoprotein and lipid fraction profiles, quantified using nuclear magnetic resonance, in a cohort of 844 healthy blood donors, integrating standard univariate and multivariate analysis with predictive modeling and network analysis. We observed a strong association of lipoprotein and lipid main fraction profiles with sex and age. Our results suggest an age-dependent remodulation of lipase lipoprotein activity in men and a change in the mechanisms controlling the ratio between esterified and non-esterified cholesterol in both men and women.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yao Tang ◽  
Jingshi Pan ◽  
Biqing Li ◽  
Suying Zhao ◽  
Liguo Zhang

AbstractCo-combustion of municipal excess sludge (ES) and coal provides an alternative method for disposing ES. The present study aims to investigate the residual and ecological risk of heavy metals in fly ash from co-combustion of ES and coal. The total concentration and speciation distribution of heavy metals, characterization of SEM, EDX, XRD and leaching test were carried out to assess the fly ash in this study. The results showed that the total concentrations of Cu, Zn and Mn were higher than others in fly ash, and most heavy metals were concentrated in fine particles. For Cd, Cr and Pb, the percentages of speciation of F4 and F5 were all over 90%, suggesting the relatively lower leaching toxicity. The leaching percent of all heavy metals was lower than 5% by two diluted HNO3 solutions for fly ash. The potential ecological risks increased with the decrease of particle size of fly ash, and Cd accounted for the main fraction for ecological risk despite of lower concentration in comparison to other measured heavy metals.


2020 ◽  
Author(s):  
Zbigniew Grobelny ◽  
Justyna Jurek-Suliga ◽  
Sylwia Golba

AbstractCesium hydroxide monohydrate (CsOH·H2O) activated by cation complexing agents, i.e., 18C6 or C222 was applied as initiator of monosubstituted oxiranes polymerization. Propylene oxide (PO), 1,2-butylene oxide (BO), styrene oxide (SO) and some glycidyl ethers were used as monomers. All processes were carried out in tetrahydrofuran solution at room temperature. Such polymers, as PPO-diols, PBO-diols and PSO-diols, are unimodal and have molar masses Mn = 2000–5100. Their dispersities are rather high (Mw/Mn = 1.17–1.33). Moreover, PPO-diols and PSO-diols are not contaminated by monools with unsaturated starting groups. Poly(glycidyl ether)s are, in general, polymodal. For example, poly(isopropyl glycidyl ether)-diols are bi- or trimodal, whereas poly(allyl glycidyl ether)-diols possess two or even six fractions. Molar masses of main fraction are 4200–6400, and the second fraction is much lower, namely 600–2600. Dispersities of some fractions are very low (Mw/Mn = 1.01–1.07). Polymodality of polymers obtained was discussed in terms of the formation of two or more species propagating with different rate constants. Graphic abstract


2020 ◽  
pp. 69-72
Author(s):  
K.B. Gurieva ◽  
S.L. Beletsky ◽  
N.A. Khaba

The article presents the results of evaluating the protein complex of wheat from different growing areas, stored in the silos of elevators for 6 years. It is shown that the protein content and quantity and quality of gluten changes slightly during long-term storage; the main fraction of wheat protein substances is a low molecular fraction up to 3 kD. There were no changes in the milling and baking characteristics of wheat for the period of 4-6 years of storage.


2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Lan Zheng ◽  
Yaohong Ma ◽  
Yunjuan Zhang ◽  
Qingjun Meng ◽  
Junhui Yang ◽  
...  

This study demonstrates that Thelephora ganbajun had a strong ability to absorb zinc, and zinc can be compartmentally stored in the small vesicles and mainly accumulated in the form of zinc-enriched polysaccharides (zinc content was 25.0±1.27 mg/g). Mycelia zinc polysaccharides (MZPS) and its fractions were isolated. The main fraction (MZPS-2) with the highest antioxidant activity in vitro was composed of mannose : galacturonic acid : glucose : galactose in a molar ratio of 61.19 : 1 : 39.67 : 48.67, with a weight-averaged molecular weight of 5.118×105 Da. MZPS-2 had both α-pyranose and β-pyranose configuration and had a triple helical conformation. By establishing zebrafish models, we found that MZPS-2 can significantly scavenge free radicals, reduce the generation of reactive oxygen species caused by inflammation, and inhibit the recruitment of neutrophils toward the injury site. Therefore, MZPS-2 exhibited antioxidant and anti-inflammatory effects and can be used as a zinc supplement with specific biological activities to alleviate zinc deficiency complications, such as chronic oxidative stress or inflammation.


Agronomy ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 802 ◽  
Author(s):  
Carla Guijarro-Real ◽  
Adrián Rodríguez-Burruezo ◽  
Ana Fita

Wall rocket is a leafy vegetable with pungent flavor related to the presence of isothiocyanates (ITCs). Despite interest in it as a crop of high organoleptic quality, the variability of the volatile profile in the species remains unknown. Twenty-four populations grown under a greenhouse were evaluated. A considerable diversity for the total levels of volatiles was found, providing information of the aroma intensity among accessions. ITCs represented the main fraction. Allyl ITC was the main compound, and levels showed up to 6-fold difference among populations. The esters fraction was mainly represented by cis-3-hexenyl isovalerate and cis-3-hexenyl butyrate, with 20-fold differences among populations. Additionally, the content in sinigrin was evaluated as main GSL in wall rocket. Differences reached up to 13-fold. These results suggest that some populations can be used to develop highly pungent varieties, whereas some others can be selected for mild-pungent varieties, as it is the case of DER045 with low levels of ITCs and high in esters. The presence of several ITCs in the profile also suggested the presence of other novel GSLs. Overall, the work increases the knowledge in the variability of wall rocket for the volatile profile and sinigrin accumulation, a starting point for future breeding programs.


2020 ◽  
Vol 79 (8) ◽  
pp. 4005-4020 ◽  
Author(s):  
Elena Benedetta Masi ◽  
Gabriele Bicocchi ◽  
Filippo Catani

Abstract Soil organic matter (SOM) represents a main fraction of superficial soil characterized by a mechanical-hydrological behaviour different from that of the inorganic fractions. In this study, a method to measure the SOM content was applied to 27 selected sites in Tuscany (central Italy) characterized by the presence of soil types common in the region: cambisols and regosols. The method included the contribution from root fragments, which is a fraction often neglected or underestimated in measurements, in the overall estimate of the SOM content. The retrieved SOM contents were analysed considering the vegetation cover at the sites and the selected attributes of geological interest, such as geotechnical parameters and the mineralogical composition of the soils. The SOM normalized to the bulk samples ranges between 1.8 and 8.9% by weight, with the highest values of the SOM content being associated with vegetation cover classes of forest and woodlands without shrubs. The SOM values showed close relationships with the abundance of the finer fractions (silt and clay) of the soil samples, and considering the relations with geotechnical properties, moderate correlations were found with the plasticity index, unit weight and effective friction angle, overall demonstrating the importance of considering SOM when the geotechnical and hydrological properties of soils are evaluated.


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