The composition of seed and seed oils of taramira(Eruca sativa)

The seeds ofEruca sativa, commonly known as taramira, were found to contain 4.1% moisture, 27.8% oil, 27.4% protein and 6.6% ash. Atomic absorption spectrophotometric analysis indicated calcium and potassium levels of 1186 and 1116 mg/100 g of whole seed, respectively. Other mineral contents also are reported. The seed oil had a specific gravity of 0.910, refractive index of 1.4680 (at 40 C), iodine value of 137.0, saponification value of 168.1 and a free fatty acid content of 2.3% (as oleic acid). Gas chromatographic analysis of the oil revealed high levels of linolenic acid (36.2%) and relatively low levels of erucic acid (10.3%).     

Thermoelectric composite structure with desirable mechanical properties for high-performance multi-functional applications

Thermoelectric (TE) structures based on energy harvesting technology have played a vital role in wide-reaching applications. In this study, a composite structure consisting of a glass fabric covered with a nanocomposite membrane (polyacrylonitrile [PAN]/carbon nanotube [CNT]/copper oxide nanoparticle [CuO]) was prepared to provide thermoelectric conversion. The performance of the TE composite structure was evaluated by analyzing the mechanical properties, thermoelectric properties, and the ability of the structure to power small electronic equipment. The results showed that the nanocomposite membrane was effective in improving the electrical properties, whereas the glass fabric could significantly suppress the thermal conductivity. The results suggest that the glass fabric covered with nanocomposite fibers containing nanofillers (15 wt% CNT & 15 wt% CuO) has a high potential to enhance the resistance against external force by 56% on average, compared to the uncovered glass fabric. Besides the power factor of the TE composite structure can reach up to 19.61 μW m⁻¹ K⁻², which can power an output voltage of 3.2 V at a temperature difference from 20 to 80°C.     

Fluorinated copolyimide membranes for sour mixed-gas upgrading

Three random and two block 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA)-based copolyimides with different 6FpDA:Durene molar ratio varying from 25 to 80% were prepared and characterized. The pure-gas permeation data of their membranes were investigated at 100 psi and 22 °C. The CO₂/CH₄ ideal selectivity coefficient increased to around 47 with the increase of the 6FpDA content to 80% in the copolymer backbone while the CO₂ permeability coefficient found to be the highest (378 barrer) with highest Durene content copolymer. Based on its attractive pure-gas permeation properties(CO₂/CH₄ = 47), 6FDA-6FpDA/6FDA-Durene (4:1) block copolyimide was selected for further analyses, where the effect of pressure and temperature on its gas transport properties was evaluated. Furthermore, the mixed-gas permeation properties were investigated using multicomponent sweet and sour gas mixtures prepared from N₂ (30% or 10%), CH₄ (59%), C₂H₆ (1%), CO₂ (10%), and H₂S (0% or 20%)accordingly. The sweet mixed-gas CO₂/CH₄ selectivity and CO₂ permeability coefficients of 6FDA-6FpDA/6FDA-Durene (4:1) are around 39 and 45 barrer, respectively, at elevated pressure (800 psi). The polymer, however, showed nonideal behavior when subjected to high H₂S-content gas mixture (20 vol. % H₂S), where the CO₂/CH₄ selectivity value dropped to around 21 and the H₂S/CH₄ selectivity coefficient is 13. The CO₂ and H₂S permeability coefficients are 42 and 26 barrer, respectively, at an upstream pressure up to 500 psi. When plotted on the combined acid gas permeability-selectivity curve, the polymer separation efficiency was nearby the high-performing polymers reported in the literature, and way superior to the industrial standard glassy polymer, cellulose acetate, used currently in gas separation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48336.     

Application of the PR-EOS with C7+ Splitting to Model Fluid Properties in a Large Two-Phase Petroleum Reservoir

The use of equations of state (EOS) to model fluid properties is necessary in order to have an internally consistent set of PVT properties, which is essential, especially, when it is desired to use compositional simulators to model two-phase reservoirs. In this article, the 3-parameter Peng-Robinson equation of state along with single carbon number (SCN) splitting of the C₇₊ fraction are used to model a major onshore reservoir in Abu Dhabi that has horizontal and vertical fluid properties variations. Extensive screening and checking of PVT data of the field was necessary to develop this model. Also, extensive verification of the developed model was accomplished by comparing its results to data external to the model. Results of this article indicate the capability of using multiple well PVT analysis within the three-parameter Peng-Robinson EOS to model complex two-phase reservoirs such as this one. We describe the process of building up the model and the challenges involved in performing this task, which include proper selection of representative experimental data to build the model, along with extensive screening and data quality these data, and the model verification so that we have the confidence that one EOS model that can predict the reservoir fluid PVT properties.     

Utilization of a triple hexagonal split ring resonator (SRR) based metamaterial sensor for the improved detection of fuel adulteration

Journal of Materials Science: Materials in Electronics - In this work, a triple hexagonal split ring resonator incorporated metamaterial sensor is proposed for the improved detection of fuel...     

Structural Determinants of Substrate Specificity of SplF Protease from Staphylococcus aureus

Accumulating evidence suggests that six proteases encoded in the spl operon of a dangerous human pathogen, Staphylococcus aureus, may play a role in virulence. Interestingly, SplA, B, D, and E have complementary substrate specificities while SplF remains to be characterized in this regard. Here, we describe the prerequisites of a heterologous expression system for active SplF protease and characterize the enzyme in terms of substrate specificity and its structural determinants. Substrate specificity of SplF is comprehensively profiled using combinatorial libraries of peptide substrates demonstrating strict preference for long aliphatic sidechains at the P1 subsite and significant selectivity for aromatic residues at P3. The crystal structure of SplF was provided at 1.7 Å resolution to define the structural basis of substrate specificity of SplF. The obtained results were compared and contrasted with the characteristics of other Spl proteases determined to date to conclude that the spl operon encodes a unique extracellular proteolytic system.     

Poly(2-hydroxyethylmethacrylate-graft-folic acid), synthesis,solubility enhancement,and release dynamic of folic acid

A series of poly (2-hydroxyethylmethacrylate-graft-folic acid) (FAHEMA) systems are synthesized by grafting of folic acid (FA) into poly (2–hydroxyethylmethacrylate) via an esterification reaction. The structure of these copolymers is confirmed by NMR and CHN analyses. The thermal behavior of these materials is characterized by DSC and TGA analyses. The surface morphology of FAHEMA films before and after the release process is examined by the SEM method. The cumulative FA released in different pH media from FAHEMA materials occurred via a retro-esterification reaction at body temperature during 72 h in which the influence of the swelling degree of PHEMA, the FA content and pH media on the dynamic release is widely investigated. The results obtained revealed that the solubility of FA in water deduced from the release process is widely improved compared with literature reports. It is also revealed that the diffusion of water in different pH media through the PHEMA matrix and that of FA through FAHEMA materials perfectly obeyed the Fickian models. It was deduced from the kinetic study that the release performance is obtained with the copolymers containing initially 10 and 20 wt% of FA contents.     

Identification of Highly Potent Protein Kinase C‐Related Kinase 1 Inhibitors by Virtual Screening,Binding Free Energy Rescoring,and in vitro Testing

Despite the considerable interest in protein kinase C‐related kinase 1 (PRK1) as a target in cancer research, there is still a lack of PRK1 inhibitors with suitable selectivity profiles and physicochemical properties. To identify new PRK1 inhibitors we applied a virtual screening approach, which combines ensemble docking, minimization of the protein–ligand complex, binding free energy calculations, and application of quantitative structure–activity relationship (QSAR) models for predicting in vitro activity. The developed approach was then applied in a prospective manner to screen available libraries of kinase inhibitors from Selleck and GlaxoSmithKline (GSK). Compounds that showed favorable prediction were then tested in vitro for PRK1 inhibition. Some of the hits were found to inhibit PRK1 in the low‐nanomolar range. Three in vitro hits were additionally tested in a mass‐spectrometry‐based cellular kinase profiling assay to examine selectivity. Our findings show that nanomolar and drug‐like inhibitors can be identified by the virtual screening approach presented herein. The identified inhibitors are valuable tools for gaining a better understanding of PRK1 inhibition, and the identified hits can serve as starting points for further chemical optimization.     

The Impact of Flow Experience and Personality Type on the Intention to Use Virtual World

Virtual World (VW) had gained and lost its popularity over the past decades. Although people were initially excited about the potential of such technology, the original excitement has not been maintained and the VW has lost its reputation. We design an experimental study to learn about the factors that impact the intention to use or not use VW (i.e., Second Life, SL). Our proposed model is based on the Theory of Reasoned Action, Technology Acceptance Model, Embodied Social Presence theory, Flow theory, and Jungian personality theory. Over 160 students participated in this study and the results support our proposed model, where a positive flow experience with VW influences the attitude towards VW, in turn influencing intention to use VW. Furthermore, VW flow experience can itself be impacted by personality of the individuals behind the avatars in VW, perceived peer influence, perceived usefulness, and familiarity with VW.     

Effect of blending and emulsification on thermal behavior, solid fat content, and microstructure properties of palm oil-based margarine fats

The ability of palm oil (PO) to crystallize as beta prime polymorph has made it an attractive option for the production of margarine fat (MF). Palm stearin (PS) expresses similar crystallization behavior and is considered one of the best substitutes of hydrogenated oils due to its capability to impart the required level of plasticity and body to the finished product. Normally, PS is blended with PO to reduce the melting point at body temperature (37 °C). Lipid phase, formulated by PO and PS in different ratios were subjected to an emulsification process and the following analyses were done: triacylglycerols, solid fat content (SFC), and thermal behavior. In addition, the microstructure properties, including size and number of crystals, were determined for experimental MFs (EMFs) and commercial MFs (CMFs). Results showed that blending and emulsification at PS levels over 40 wt% significantly changed the physicochemical and microstructure properties of EMF as compared to CMF, resulting in a desirable dipalmitoyl-oleoyl-glycerol content of less than 36.1%. SFC at 37 °C, crystal size, crystal number, crystallization, and melting enthalpies (ΔH) were 15%, 5.37 μm, 1425 crystal/μm(2), 17.25 J/g, and 57.69J/g, respectively. All data reported indicate that the formation of granular crystals in MFs was dominated by high-melting triacylglycerol namely dipalmitoyl-oleoyl-glycerol, while the small dose of monoacylglycerol that is used as emulsifier slowed crystallization rate. Practical Application: Most of the past studies were focused on thermal behavior of edible oils and some blends of oils and fats. The crystallization of oils and fats are well documented but there is scarce information concerning some mechanism related to crystallization and emulsification. Therefore, this study will help to gather information on the behavior of emulsifier on crystallization regime; also the dominating TAG responsible for primary granular crystal formations, as well as to determine the best level of stearin to impart the required microstructure properties and body to the finished products.