This contribution reports on properties of low-density polyethylene-based composites filled with different amounts of graphene nanoplatelets. The studied samples were prepared in the form of films by ...means of the precoating technique and single screw melt-extrusion, which yields a highly ordered arrangement of graphene flakes and results in a strong anisotropy of composites morphology. The performed tests of gas permeability reveal a drastic decrease of this property with increasing filler content. A clear correlation is found between permeability and free volume fraction in the material, the latter evaluated by means of positron annihilation spectroscopy. A strong anisotropy of the thermal conductivity is also achieved and the thermal conductivity along the extrusion direction for samples filled with 7.5 wt % of GnP (graphene nanoplatelets) reached 2.2 W/m·K. At the same time, when measured through a plane, a slight decrease of thermal conductivity is found. The use of GnP filler leads also to improvements of mechanical properties. The increase of Young's modulus and tensile strength are reached as the composites become more brittle.
The basic process to reduce the phosphate ions in aquatic environments is to move the phosphorus circulation processes on the water–sediment phase boundary towards depositing it in the solid phase ...through chemical precipitation or adsorption. Modern technologies for removal of phosphorus can be based on cheap and environmentally friendly natural polysaccharides modified with multivalent metals. In this study alginate/goethite hydrogel composite has been investigated for phosphate uptake from aqueous solutions. The composite was produced by a cross-linking reaction between sodium alginate and calcium chloride in six configurations of suspensions, which differed in goethite content. In all cases, spherical and durable capsules of alginate/goethite composite were produced. In laboratory tests, mechanical stability of the capsules at various temperatures and the coexisting ions of lake water were tested. Chemical composition of the aquatic environment had a strong influence on their mechanical stability. Static batch adsorption of phosphate studies were carried out for two adsorbents: goethite and alginate/goethite composite. The goethite gelation resulted in almost double growth of sorption capacity in the case of adsorption from deionized water and, on average, a 50% growth in adsorption from the environmental water compared to raw goethite. The alginate/goethite adsorbent removed phosphate in a wide pH spectrum—from 4 to 10. Results suggest that the proposed adsorbent has potential for the removal of phosphate from contaminated water.
The in vitro antifungal potency of six series of 4-arylthiosemicarbazides was evaluated. Two isoquinoline derivatives with an ortho-methoxy or ortho-methyl group at the phenyl ring were the most ...potent antifungal agents. Molecular modeling studies and docking of all 4-arylthiosemicarbazides into the active sites of sterol 14α-demethylase (CYP51), topoisomerase II (topo II),
l
-glutamine:
d
-fructose-6-phosphate amidotransferase (GlcN-6-P), secreted aspartic proteinase (SAP),
N
-myristoyltransferase (NMT), and UDP-N-acetylmuramoyl-
l
-alanine:
d
-glutamate ligase (MurD) indicated the importance of both structural and electronic factors in ligand recognition and thus for the antifungal effectiveness of 4-arylthiosemicarbazides. A possible antifungal target was identified (NMT) and isoquinoline-thiosemicarbazides showed more favorable affinity than the native ligand.
Figure
Electrostatic potential surface of isoquiniline derivative compound 6o with antifungal activity
Forecasts to 2030 indicate that demand for electricity will increase from 2% to 3% per year, and due to the observed high rate of development of the world economy, energy demand will continue to ...increase. More efficient use of primary energy has influence on reduction emissions and consumption of fuel. Besides, reducing the amount of fuel burned, it reveals a beneficial effect on the environment. Since extraction-back pressure turbines have some limitations, including the restriction of electricity production due to limited heat consumption in summer. The paper discusses the possibilities of integrating the adsorption aggregate with a combined cycle gas turbine and its impact on the operation of all devices. Simulations are performed on Sim tech IPSEPro software. The obtained results confirm that the adsorption aggregate, using a low grade of thermal energy, does not affect the operation of the gas and steam cycle and allows the production of electricity at a constant level. The calculated chemical fuel energy utilisation factor was 85.7% in cogeneration and 75.6% in trigeneration. These factors indicated a reduced utilisation of chemical fuel energy; however, this reduction is caused by a lower COP for adsorption chillers. Besides, the adsorption aggregate additionally generates chilled water for air conditioning or other technological processes, which stands for an added value of the innovative concept proposed in the paper.
A previous study showed that prebiotics and synbiotics administered in ovo into the egg air cell on the 12th day of incubation enhance the growth and development of chickens. However, the influence ...of this procedure on the development and efficiency of the innate immune system of broiler chickens is unclear. Therefore, the aim of this study was to evaluate whether the early (on the 12th day of embryo development) in ovo administration of selected prebiotics (inulin - Pre1 and Bi
tos - Pre2) and synbiotics (inulin + Lactococcus lactis subsp. lactis IBB SL1 - Syn1 and Bi
tos + L. lactis subsp. cremoris IBB SC1 - Syn2) influences the innate immune system.
Chickens (broiler, Ross 308) that were treated with Pre1 exhibited a decreased H/L ratio on D7, but an increased H/L ratio was observed on D21 and D35. In the remaining experimental groups, an increase in the H/L ratio was observed on D21 and D35. The oxidative potential of leukocytes measured using the NBT test increased on D21 in Pre2 and Syn1 groups. The rate of the phagocytic ability of leukocytes increased in Pre1 and Syn1 groups on D21. The phagocytic index decreased in Pre1 and Syn2 groups on D21 and D35. Concurrently, the count of WBC in circulating blood decreased on D21 in Pre1, Pre2, and Syn1 groups. The hematocrit value was increased in Syn1 chickens on D21, in Pre1 chickens on D35, and in Syn2 chickens on both time points.
Early in ovo treatment of chicken embryos with prebiotics and synbiotics may temporarily modulate not only the production/maturation of leukocytes but also their reactivity.
Binding phosphate at participation of alginate/FeCl
3
capsules was studied with laboratory experiments. The hydrogel microcapsules were obtained with the dropping-in method, by gelation of sodium ...alginate water solution by iron (III) chloride solution. Phosphate adsorption characteristics were studied in a static batch system with respect to changes in contact time, initial phosphates concentration, pH of solution, and temperature. After 24 h of the tests, average 87.5% of phosphate ions were removed from the natural water solutions; after 48 h, an equilibrium was reached. The adsorption data were well fit by the Freundlich isotherm model. Parameter
k
of the isotherms amounted from 43.4 to 104.7, whereas parameter
n
amounted from 0.362 to 0.476. The course of processes of phosphate adsorption and iron desorption to aquatic phase, as well as changes in pH, suggests that phosphate adsorption is a major mechanism of phosphate removal, whereas simultaneously, but at a much lower degree, a process of precipitation of phosphate by iron (III) ions released from the capsules to the solution takes its place. Parameters calculated in the Freundlich isotherm equation show that by using several times smaller amounts of iron, it is possible to remove similar or bigger amounts of phosphorus than with other adsorbents containing iron. The alginate/FeCl
3
adsorbent removes phosphate in a wide pH spectrum—from 4 to 10. Results suggest that the proposed adsorbent has potential in remediation of contaminated waters by phosphate.
The effect of the
application of selected prebiotics and synbiotics on the humoral immune response against T-dependent (SRBC) and T-independent (dextran) antigens and delayed-type hypersensitivity ...(DTH) to phytohemagglutinin was studied. On the 12th day of incubation, 800 eggs (Ross 308) were divided into five groups and injected into the egg air chamber with prebiotic inulin (Pre1), Bi
tos (Pre2), a synbiotic composed of inulin and
subsp.
IBB SL1 (Syn1), a synbiotic composed of Bi
tos and
subsp.
IBB SC1 (Syn2), and physiological saline (control group; C). The chickens were immunized twice at the 7th and 21st day of life with SRBC and dextran. A DTH test was performed on the 7th, 21st, and 35th day. The application of prebiotics and synbiotics had no significant effect on the humoral immune response. SRBC-immunized
Pre1- and Pre2-treated chickens showed significantly higher serum IgG levels than the control. A significant effect on the DTH reaction was detected on the 7th (Pre1 < C) and 21st (Pre2 > Syn2) day. However; Bi
tos may transiently stimulate the cellular immune response on the 21st day. It may be concluded that the application of inulin in an egg air chamber on the 12th day of incubation may stimulate the secondary immune response. The inulin-treated group exhibited a lower mortality rate than the control group.
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