Natural fibers are increasingly being used as reinforcement in commercial thermoplastics due to their low cost, high specific properties and renewable nature. While the maleic anhydride modified ...polypropylene (MAPP) is most commonly used as compatibilizer to improve interfacial adhesion between hydrophilic wood–fibers and hydrophobic polypropylene, in this study, a novel compatibilizer (
m-TMI-g-PP) with isocyanate functional group was synthesized by grafting
m-isopropenyl-α,α-dimethylbenzyl-isocyanate (
m-TMI) onto isotactic polypropylene (PP) in a twin screw extruder. The effect of filler concentration on the mechanical properties of wood–fiber filled composites, prepared by using
m-TMI-g-PP as the compatibilizer, was investigated. The addition of the compatibilizer resulted in greater reinforcement of composites, as indicated by the improvement in mechanical properties. Tensile strength of composites so prepared increased by almost 45%, whereas 85% increase in flexural properties was observed. However the addition of wood–fibers resulted in a decrease in elongation at break and impact strength of the composites.
Antiferromagnets are hard to control by external magnetic fields because of the alternating directions of magnetic moments on individual atoms and the resulting zero net magnetization. However, ...relativistic quantum mechanics allows for generating current-induced internal fields whose sign alternates with the periodicity of the antiferromagnetic lattice. Using these fields, which couple strongly to the antiferromagnetic order, we demonstrate room-temperature electrical switching between stable configurations in antiferromagnetic CuMnAs thin-film devices by applied current with magnitudes of order 10⁶ ampere per square centimeter. Electrical writing is combined in our solid-state memory with electrical readout and the stored magnetic state is insensitive to and produces no external magnetic field perturbations, which illustrates the unique merits of antiferromagnets for spintronics.
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•Conductivity and fluorescence probe studies for CTAB/DTAB–glycyl dipeptide system.•Decrease in CMC values for both the surfactants with glycyl dipeptide.•Micellization process is ...energetically favourable.•Entropy-enthalpy contribution to micellization has been demonstrated.•More facilitated micellization for CTAB as compare to DTAB.
The effect of cationic micelles of cetyltrimethylammonium bromide (CTAB) and dodecyltrimethylammonium bromide (DTAB) on interactions of glycyl dipeptide in aqueous medium have been studied in varying concentrations (0.001, 0.005 and 0.010mol·kg–1) at different temperatures (293.15K to 293.15K). The conductivity method has been employed to determine critical micelle concentration, CMC i.e. point of aggregation and the results have been discussed in terms of glycylglycine–CTAB/DTAB hydrophobic and electrostatic interactions in aqueous medium. The obtained CMC values reveal the fact that the micellization tendency of the surfactant increases in the presence of glycyl dipeptide. The CMC’s of CTAB and DTAB have been found to decrease from 0.87 to 0.66mmol·kg–1 and 14.2–13.7mmol·kg–1 respectively as the Glycyl dipeptide increased from 0.001 to 0.010mol·kg–1. The temperature dependence of the CMC values has been established in terms of ion–ion, ion–polar and hydrophobic–hydrophobic group interactions around the hydrophobic part of surfactants. Furthermore, the standard thermodynamic parameters of micellization have been evaluated and interpreted which enable to grasp fully the ion–ion/ion–hydrophilic interactions existing in the present ternary (surfactant–dipeptide–water) system. In addition, the pyrene fluorescence technique has been used to study the change of micropolarity produced by the interactions of surfactants with glycyl dipeptide and the aggregation behaviour (CMC determination) of surfactants.
This paper deals and addresses the query that which of the variable order operators are reasonable and regular extension of constant order operators. An irregularity is pointed out in the definition ...of variable order operators. We generalize some existing results of constant order to variable order using special functions of fractional calculus. It provides a method for considering the existence of solution for variable order fractional differential equations. Some illustrations are presented to support the validity of variable order operators. Further, we consider an application of a class of fractional initial value problems and provide the criteria of existence and uniqueness of its solution with example.
Nassella trichotoma (Nees) Hack. ex Arechav. (Serrated tussock) is an aggressive globally significant weed to agricultural and natural ecosystems. Herbicide resistant populations of this C3 perennial ...weed have emerged, increasing the need for effective wide-scale cultural control strategies. A thorough seed ecology study on two spatially distinct populations of N. trichotoma was conducted on this weed to identify differences in important environmental factors (drought, salinity, alternating temperature, photoperiod, burial depth, soil pH, artificial seed aging, and radiant heat) which influence seed dormancy. Seeds were collected from two spatially distinct populations; Gnarwarre (38 O 9' 8.892'' S, 144 O 7' 38.784'' E) and Ingliston (37O 40' 4.44'' S, 144 O 18' 39.24'' E) in December 2016 and February 2017, respectively. Twenty sterilized seeds were placed into Petri dishes lined with a single Whatman® No. 10 filter paper dampened with the relevant treatments solution and then incubated under the identified optimal alternating temperature and photoperiod regime of 25°C/15°C (light/dark, 12h/12h). For the burial depth treatment, 20 seeds were placed into plastic containers (10cm in diameter and 6cm in depth) and buried to the relevant depth in sterilized soil. All trials were monitored for 30 days and germination was indicated by 5mm exposure of the radicle and emergence was indicated by the exposure of the cotyledon. Each treatment had three replicates for each population, and each treatment was repeated to give a total of six replicates per treatment, per population. Nassella trichotoma was identified to be non-photoblastic, with germination (%) being similar under alternating light and dark and complete darkness conditions. With an increase of osmotic potential and salinity, a significant decline in germination was observed. There was no effect of pH on germination. Exposure to a radiant heat of 120°C for 9 minutes resulted in the lowest germination in the Ingliston population (33%) and the Gnarwarre population (60%). In the burial depth treatment, the Ingliston population and the Gnarwarre population had highest emergence of 75% and 80%, respectively at a depth of 1cm. Variation between the two populations was observed for the burial depth treatments; Gnarwarre had greater emergence than Ingliston from the 4cm burial depth, while Ingliston had greater emergence at the soil surface than Gnarwarre. The Gnarwarre population had greater overall germination than Ingliston, which could be attributed to the greater seed mass (0.86mg compared to 0.76mg, respectively). This study identifies that spatial variations in N. trichotoma's seed ecology are present between spatially distinct populations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Expired drug Dapsone was chemically modified by reacting with benzaldehyde; salicylaldehyde and the resulting product (Schiff bases) were investigated as corrosion inhibitor for mild steel in ...sulphuric acid solution. Schiff base 1 (Dapsone-benzaldehyde) and Schiff base 2 (Dapsone-salicylaldehyde) gave maximum inhibition efficiency of 95.67% and 94.23% at a concentration of 0.219 mM respectively. Addition of very small amount of KI (0.602 mM) further increased their efficiency up to 99.03% and 97.98% respectively. The observed results indicate increase in corrosion inhibition efficiency with raising the concentration of the inhibitors. The corrosion inhibition behavior was afforded by the adsorption of Schiff bases onto the mild steel following the Langmuir adsorption isotherm model via mixed physical and chemical adsorption. The synergistic influence of KI at various concentrations of the inhibitors was determined by the calculation of the synergism parameters which suggested a co-operative mechanism. DFT calculations were carried out to elucidate the mechanism of corrosion inhibition process. It was found that the protonated inhibitors are strongly adsorbed on the steel surface than the neutral inhibitors. The results suggest that the developed formulations can be used as corrosion inhibitors during industrial pickling process.
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•Schiff bases were evaluated as corrosion inhibitors for mild steel in 0.5 M H2SO4.•The synergistic effect of KI was also tested with the Schiff bases.•Maximum inhibition efficiency obtained was 96% which increased, 99% with adding KI.•Inhibitors showed mixed type behaviour with cathodic predominance.•AFM micrographs show decrease in surface roughness in the presence of inhibitors.
Location planning for urban distribution centers is vital in saving distribution costs and minimizing traffic congestion arising from goods movement in urban areas. In this paper, we present a ...multi-criteria decision making approach for location planning for urban distribution centers under uncertainty. The proposed approach involves identification of potential locations, selection of evaluation criteria, use of fuzzy theory to quantify criteria values under uncertainty and application of fuzzy TOPSIS to evaluate and select the best location for implementing an urban distribution center. Sensitivity analysis is performed to determine the influence of criteria weights on location planning decisions for urban distribution centers.
The strength of the proposed work is the ability to deal with uncertainty arising due to a lack of real data in location planning for new urban distribution centers. The proposed approach can be practically applied by logistics operators in deciding on the location of new distribution centers considering the sustainable freight regulations proposed by municipal administrations. A numerical application is provided to illustrate the approach.
Thermal performance of passive residual heat removal systems and solar heaters relies on natural convection heat transfer. However, natural convection heat transfer may lead to the thermal ...stratification in a pool. Depending on the uses, the stratification may be desirable or undesired. When the whole system subjects to seismic excitation, transient investigation of evolution of temperature distribution is pronounced and not explored numerically. Thus, this paper deals with numerical investigation of the combined interaction of heat transfer from submerged heater and liquid sloshing in a pool introduced by seismic excitation which imposed during the natural calamities (Tsunami, earthquake). First, numerical model has been developed by introducing energy equation in existing solver named “interDyMFoam” available in open-source finite volume-based OpenFOAM 4.0 tool. Further, developed model is used to reproduce the pressure data for liquid sloshing problem reported in open literature to validate the model. To further validate the proposed model, the heat transfer problem for partially filled water pool having horizontal submerged heat source is simulated and results are compared with experimental data. Numerical results are found to be in good agreement with available data for both sceneries: liquid sloshing and heat transfer individually. Utilizing the proposed model, in the current work, which has not been addressed earlier, free surface slosh height and thermal behavior of a partially filled water pool with a submerged heat exchanger for varied submergence depths are explored. Results concluded that maximum 12.3% enhancement has been found in water temperature when pool is excited as compared to without excitation.
Significance Plasmodium falciparum reticulocyte binding-like homologous protein 5 (PfRH5) is a leading blood-stage malaria vaccine candidate that elicits potent strain-transcending invasion ...inhibitory antibodies. However, it lacks both transmembrane domains and a GPI-anchor and is thus anchored to the merozoite surface through an unknown mechanism. We have demonstrated that PfRH5 and its known partner, PfRH5-interacting protein (PfRipr), associates with a conserved GPI-anchored protein, Cysteine-rich protective antigen (CyRPA), to form a complex on the merozoite surface. CyRPA was shown to be GPI-linked, refractory to knockout, and like PfRH5, elicited potent strain-transcending invasion inhibitory antibodies. This discovery elucidates the formation of a previously unidentified PfRH5/PfRipr/CyRPA protein complex on the merozoite surface, which facilitates the PfRH5–Basigin interaction and offers another highly conserved, potent target (CyRPA) for novel antimalarial strategies that could abrogate formation of this crucial complex.
Erythrocyte invasion by Plasmodium falciparum merozoites is a highly intricate process in which Plasmodium falciparum reticulocyte binding-like homologous protein 5 (PfRH5) is an indispensable parasite ligand that binds with its erythrocyte receptor, Basigin. PfRH5 is a leading blood-stage vaccine candidate because it exhibits limited polymorphisms and elicits potent strain-transcending parasite neutralizing antibodies. However, the mechanism by which it is anchored to the merozoite surface remains unknown because both PfRH5 and the PfRH5-interacting protein (PfRipr) lack transmembrane domains and GPI anchors. Here we have identified a conserved GPI-linked parasite protein, Cysteine-rich protective antigen (CyRPA) as an interacting partner of PfRH5-PfRipr that tethers the PfRH5/PfRipr/CyRPA multiprotein complex on the merozoite surface. CyRPA was demonstrated to be GPI-linked, localized in the micronemes, and essential for erythrocyte invasion. Specific antibodies against the three proteins successfully detected the intact complex in the parasite and coimmunoprecipitated the three interacting partners. Importantly, full-length CyRPA antibodies displayed potent strain-transcending invasion inhibition, as observed for PfRH5. CyRPA does not bind with erythrocytes, suggesting that its parasite neutralizing antibodies likely block its critical interaction with PfRH5-PfRipr, leading to a blockade of erythrocyte invasion. Further, CyRPA and PfRH5 antibody combinations produced synergistic invasion inhibition, suggesting that simultaneous blockade of the PfRH5–Basigin and PfRH5/PfRipr/CyRPA interactions produced an enhanced inhibitory effect. Our discovery of the critical interactions between PfRH5, PfRipr, and the GPI-anchored CyRPA clearly defines the components of the essential PfRH5 adhesion complex for P. falciparum erythrocyte invasion and offers it as a previously unidentified potent target for antimalarial strategies that could abrogate formation of the crucial multiprotein complex.
Well crystalline CeO2 nanoparticles have been successfully synthesized via solution combustion synthesis (SCS) using (NH4)2Ce(NO3)6 and C4H6O6 as oxidizer and fuel. The structural characteristics of ...as-synthesized material were investigated in terms of FESEM, HRTEM, EDS, XRD, FTIR and UV–Vis spectroscopy techniques. The surface area of synthesized CeO2 nanoscale material was obtained from BET plot. Results showed a pure, well-crystallized, flake-like mesoporous material to be formed with crystallite size of 18.86 nm. The focus of this study was to investigate the application of as-synthesized CeO2 nanomaterial for sensing and photocatalytic degradation of picric acid (PA) in its aqueous solution. It was found to be highly selective for PA detection in aqueous solution when compared with other aromatic compounds. Detection limit (0.52 µM) for PA when compared with earlier studies was found to be much better. In addition, 0.05 gm of as-synthesized CeO2 nanomaterial is found to be optimum amount ensuring maximum catalytic photodegradation of 10 ppm PA in aqueous solution. These experimental findings point out that as-synthesized CeO2 nanomaterial can be efficiently used as an effective chemical sensor and photocatalyst.
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