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Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 399
Author(s):  
Carla Monteiro Leal ◽  
Suzana Guimarães Leitão ◽  
Leonardo Luiz Oliveira de Mello ◽  
Isabel de Castro Rangel ◽  
Carlos Vinicius Azevedo da Silva ◽  
...  

Siparuna glycycarpa occurs in the Amazon region, and some species of this genus are used in Brazilian folk medicine. A recent study showed the inhibitory effect of this species against influenza A(H1N1)pdm09 virus, and in order to acquire active fractions, a polar solvent system n-butanol-methanol-water (9:1:10, v/v) was selected and used for bioassay-guided fractionation of n-butanol extract by centrifugal partition chromatography (CPC). The upper phase was used as stationary phase and the lower phase as mobile (descending mode). Among the collected fractions, the ones coded SGA, SGC, SGD, and SGO showed the highest antiviral inhibition levels (above 74%) at 100 µg·mL−1 after 24 h of infection. The bioactive fractions chemical profiles were investigated by LC-HRMS/MS data in positive and negative ionization modes exploring the Global Natural Products Social Molecular Networking (GNPS) platform to build a molecular network. Benzylisoquinoline alkaloids were annotated in the fractions coded SGA, SGC, and SGD collected during elution step. Aporphine alkaloids, O-glycosylated flavonoids, and dihydrochalcones in SGO were acquired with the change of mobile phase from lower aqueous to upper organic. Benzylisoquinolinic and aporphine alkaloids as well as glycosylated flavonoids were annotated in the most bioactive fractions suggesting this group of compounds as responsible for antiviral activity.


2021 ◽  
Author(s):  
Rini Setiati ◽  
Muhammad Taufiq Fathaddin ◽  
Aqlyna Fatahanissa

Microemulsion is the main parameter that determines the performance of a surfactant injection system. According to Myers, there are four main mechanisms in the enhanced oil recovery (EOR) surfactant injection process, namely interface tension between oil and surfactant, emulsification, decreased interfacial tension and wettability. In the EOR process, the three-phase regions can be classified as type I, upper-phase emulsion, type II, lower-phase emulsion and type III, middle-phase microemulsion. In the middle-phase emulsion, some of the surfactant grains blend with part of the oil phase so that the interfacial tension in the area is reduced. The decrease in interface tension results in the oil being more mobile to produce. Thus, microemulsion is an important parameter in the enhanced oil recovery process.


Author(s):  
Slamet Priyanto ◽  
Ronny Windu Sudrajat ◽  
Suherman Suherman ◽  
Bambang Pramudono ◽  
Teguh Riyanto ◽  
...  

Recently, the increase in fuel oil demand was not supported by petroleum production due to the low productivity of old wells. Furthermore, an appropriate technology, such as Enhanced Oil Recovery (EOR) technology, is needed to maximize the productivity of the old well. Therefore, the purpose of this study was to synthesize a polymeric surfactant for the EOR process from sodium lignosulfonate (SLS) and polyethylene glycol (PEG) in various SLS to PEG ratios, namely 1:1 (PS1), 1:0.8 (PS2), and 1:0.5 (PS3). The surfactants were characterized using several methods, such as Fourier Transform-Infrared spectroscopy (FT-IR), compatibility, stability, viscosity, and phase behavior tests. The performance of the surfactants for the EOR process in different brine solution concentrations (16,000 ppm and 20,000 ppm) was also studied. The result showed that the introduction of the PEG molecule to the surfactant had been successfully conducted as FT-IR analysis confirmed. The surfactant's hydrophilicity increased with the introduction of PEG due to the increase of the ether group. A Winsor Type I or lower phase microemulsion was formed due to the high hydrophilicity. The highest oil yield (79 %) was obtained by PS1 surfactant, which has the highest PEG dosage, in a brine solution of 1,600 ppm. Therefore, it was concluded that the introduction of PEG could increase the hydrophilicity, viscosity, and EOR performance.


2021 ◽  
Author(s):  
Ergun Simsek ◽  
Seyed Ehsan Jamali Mahabadi ◽  
Ishraq Md Anjum ◽  
Curtis R. Menyuk
Keyword(s):  

Marine Drugs ◽  
2021 ◽  
Vol 19 (9) ◽  
pp. 517
Author(s):  
Daniela Bárcenas-Pérez ◽  
Antonín Střížek ◽  
Pavel Hrouzek ◽  
Jiří Kopecký ◽  
Marta Barradas ◽  
...  

Phaeodactylum tricornutum is a rich source of fucoxanthin, a carotenoid with several health benefits. In the present study, high performance countercurrent chromatography (HPCCC) was used to isolate fucoxanthin from an extract of P. tricornutum. A multiple sequential injection HPCCC method was developed combining two elution modes (reverse phase and extrusion). The lower phase of a biphasic solvent system (n-heptane, ethyl acetate, ethanol and water, ratio 5/5/6/3, v/v/v/v) was used as the mobile phase, while the upper phase was the stationary phase. Ten consecutive sample injections (240 mg of extract each) were performed leading to the separation of 38 mg fucoxanthin with purity of 97% and a recovery of 98%. The process throughput was 0.189 g/h, while the efficiency per gram of fucoxanthin was 0.003 g/h. Environmental risk and general process evaluation factors were used for assessment of the developed separation method and compared with existing fucoxanthin liquid-liquid isolation methods. The isolated fucoxanthin retained its well-described ability to induce nuclear translocation of transcription factor FOXO3. Overall, the developed isolation method may represent a useful model to produce biologically active fucoxanthin from diatom biomass.


2021 ◽  
Author(s):  
Luis Hernández ◽  
Hector Carreón ◽  
Arnoldo Jacuinde

Abstract In high carbon steel manufacture, segregation is a common problem that compromises the quality and performance of cast products. When they are rolled or forged, hard metallurgical phases can develop, promoting material embrittlement. To detect the segregation presence, traditionally, it is analyzed by macro-attack (according to the ASTM 381 standard). However, this methodology is limited to the subjective interpretation of the quality inspector, and also it is dangerous. Non-destructive means represent an agile alternative for quality control because they are sensitive to the chemical composition and microstructure of the steel. Through conventional ultrasound technique, an increase in attenuation coefficient was detected in the area of greater segregation and lower values in regions with greater chemical homogeneity. On the other hand, the longitudinal wave velocity was lower in the segregated region and higher in the zone with less segregation. Furthermore, by some mathematical relationships and wave speeds, Poisson’s ratio Young’s and shear modulus were obtained, which are related to the ease of rolling in steel. Finally, Eddy currents and impedance plane determined that the segregation region has a lower phase angle, and therefore, a higher electrical conductivity concerning the zones of less segregation.


Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1997
Author(s):  
Luigi Barrea ◽  
Giovanna Muscogiuri ◽  
Gabriella Pugliese ◽  
Giulia de Alteriis ◽  
Maria Maisto ◽  
...  

In this case-control, cross-sectional, observational study, we evaluated circulating trimethylamine n-oxide (TMAO) levels, a gut-derived metabolite associated with inflammation and cardiometabolic risk, in patients with hidradenitis suppurativa (HS), a highly disabling inflammatory skin disease associated with an elevated prevalence of comorbidities, especially cardiovascular and metabolic diseases. In this study, we enrolled 35 naive-treatment patients with HS and 35 controls, matched for sex, age, and body mass index (BMI). HS Sartorius score was 49.0 (33.0–75.0), while according to the Harley system 12 and 23 patients presented grade 1 and grade 2 severity, respectively. HS patients had a lower adherence to the Mediterranean diet (MD) (p = 0.002), lower phase angle (PhA) (p < 0.001), and higher circulating TMAO levels (p < 0.001) than the control group. HS patients with grade 2 rather than grade 1 of Harley grade severity showed a higher BMI (p = 0.007), waist circumference (p = 0.016), total energy intake (p = 0.005), and lower PhA (p < 0.001) and adherence to the MD (p = 0.003). Of interest, patients with Hurley grade 2 of severity exhibited higher circulating TMAO levels (p < 0.001) compared to grade 1. Circulating TMAO levels showed a positive correlation with HS Sartorius score even after adjustment for confounding covariates, including BMI, waist circumference, adherence to the MD, total energy intake, and PhA (r = 0.570, p = 0.001). Using a linear regression model, circulating TMAO levels and PhA were the main predictors of the clinical severity of HS.


2021 ◽  
Author(s):  
Omar Siddiqui

The applicability of utilizing a variety of thermal mass including phase change materials with commonly used building materials is investigated through the use of simulations and physical testing. The thermal performance and occupant comfort potential of a novel solid-solid phase change material, known as Dal HSM, is compared and contrasted to commonly available forms of thermal mass. Detailed experimentation is conducted to successfully integrate Dal HSM with gypsum and concrete. The measurement of physical characteristics such as compressive strength and modulus of rupture is conducted to ensure that the PCM-composite compound retains the structural integrity to be utilized in a typical building. The use of thermal mass in the Toronto Net Zero house was found to contribute to energy savings of 10-15% when different types of thermal mass were used. The comfort level of the indoor occupants was also found to increase. The performance of Dal HSM was found to be comparable to a commercially available PCM known as Micronal in the heating mode. The cooling mode revealed that Dal HSM provided slightly lower energy savings when compared to Micronal due to a lower phase transition temperature and latent heat. The performance of physical test revealed a decrease in the compressive strength as the concentration of Dal HSM was increased in the PCM-gypsum specimens. Tests were also performed to analyze the impact of increasing the PCM concentration on the flexural strength of PCM-gypsum composite.


2021 ◽  
Author(s):  
Omar Siddiqui

The applicability of utilizing a variety of thermal mass including phase change materials with commonly used building materials is investigated through the use of simulations and physical testing. The thermal performance and occupant comfort potential of a novel solid-solid phase change material, known as Dal HSM, is compared and contrasted to commonly available forms of thermal mass. Detailed experimentation is conducted to successfully integrate Dal HSM with gypsum and concrete. The measurement of physical characteristics such as compressive strength and modulus of rupture is conducted to ensure that the PCM-composite compound retains the structural integrity to be utilized in a typical building. The use of thermal mass in the Toronto Net Zero house was found to contribute to energy savings of 10-15% when different types of thermal mass were used. The comfort level of the indoor occupants was also found to increase. The performance of Dal HSM was found to be comparable to a commercially available PCM known as Micronal in the heating mode. The cooling mode revealed that Dal HSM provided slightly lower energy savings when compared to Micronal due to a lower phase transition temperature and latent heat. The performance of physical test revealed a decrease in the compressive strength as the concentration of Dal HSM was increased in the PCM-gypsum specimens. Tests were also performed to analyze the impact of increasing the PCM concentration on the flexural strength of PCM-gypsum composite.


2021 ◽  
Vol 3 (1) ◽  
pp. 52-60
Author(s):  
Asad Ali ◽  
Qaisar Jabbar ◽  
Humayun Kiani

Scrambling in Clausal-Internal is accounted for employing minimalist program as a theoretical framework on Urdu Naturalistic data in this study. For empirical evidence, an Urdu corpus has been accumulated in audio-recording forms from 100 competent Urdu speakers within the natural setting, taking Naturalist Inquiry as methodological purposes.  Employing minimalist program on Urdu data, this study vehemently postulates that the dislocation of arguments from base to host position only hinges on the phase heads— Co and vo; hence no other external devices essentially necessitate accounting for scrambling. This study highlighted scrambling in clausal-internal specifically within Indo-Aryan Languages is Universal Phase-Based parsimony, and it is only controlled by the exiting mechanism within the phase theory. Moreover, the only merge and move operations linearize the CP in a phase-based fashion while CP is a higher phase and vP is a lower phase. No additional AGRoP necessitates scrambling, but one phase successively and cyclically converges into a higher phase level, i.e. CP and the derivation matches at LF and PF interfaces satisfying Full Interpretation (FI).


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