In vitro zygotic embryo culture of Pinus peuce Gris.: Optimization of culture conditions affecting germination and early seedling growth

This study reports a protocol for the germination and early seedling growth of Pinus peuce Gris. using zygotic embryo culture. In order to overcome seed dormancy and optimize organogenesis, the effect of nutritional, plant growth regulatory and physical factors on in vitro germination and growth of isolated mature zygotic embryos of P. peuce were investigated

In vitro zygotic embryo culture of Pinus peuce Gris.: Optimization of culture conditions affecting germination and early seedling growth

This study reports a protocol for the germination and early seedling growth of Pinus peuce Gris. using zygotic embryo culture. In order to overcome seed dormancy and optimize organogenesis, the effect of nutritional, plant growth regulatory and physical factors on in vitro germination and growth of isolated mature zygotic embryos of P. peuce were investigated.Projekat ministarstva br.17301

Self-aggregation of soil humic acids with respect to their structural characteristics

The main goal of this work was to estimate the influence of carboxyl and phenolic groups, as well as aromatic, aliphatic and polysaccharide components, on the soil humic acids (HA) self-aggregation process. Soil HAs (leptosol and regosol) were separated using base resin getting fractions with different functional group contents. Blocking of carboxyl groups was performed using the esterification procedure to estimate the participation of each functional group in the HA aggregation. The presence of HA structural components was evaluated by potentiometric titration and ATR-FTIR. The aggregation was monitored at pH 3 using dynamic light scattering. Results indicated that the higher group content, the HA aggregation is less pronounced. A significant positive correlation of aliphatic C and aggregate size revealed their dominant influence in the HA self-aggregation. A lower abundance of aliphatic C in HA fractions could be considered as not sufficient to start the process. An increase of aromatic C in esters likely pointed out to its participation in hydrophobic bonding and, consequently, more pronounced aggregation. The relation of HA self-aggregate size with carboxyl and phenolic group, as well as aliphatic C, at low pH, could be considered universal regardless of the structural characteristics of the original or modified HA forms

Self-aggregation of soil humic acids with respect to their structural characteristics

The main goal of this work was to estimate the influence of carboxyl and phenolic groups, as well as aromatic, aliphatic and polysaccharide components, on the soil humic acids (HA) self-aggregation process. Soil HAs (leptosol and regosol) were separated using base resin getting fractions with different functional group contents. Blocking of carboxyl groups was performed using the esterification procedure to estimate the participation of each functional group in the HA aggregation. The presence of HA structural components was evaluated by potentiometric titration and ATR-FTIR. The aggregation was monitored at pH 3 using dynamic light scattering. Results indicated that the higher group content, the HA aggregation is less pronounced. A significant positive correlation of aliphatic C and aggregate size revealed their dominant influence in the HA self-aggregation. A lower abundance of aliphatic C in HA fractions could be considered as not sufficient to start the process. An increase of aromatic C in esters likely pointed out to its participation in hydrophobic bonding and, consequently, more pronounced aggregation. The relation of HA self-aggregate size with carboxyl and phenolic group, as well as aliphatic C, at low pH, could be considered universal regardless of the structural characteristics of the original or modified HA forms

In vitro zygotic embryo culture of Pinus peuce Gris.: Optimization of culture conditions affecting germination and early seedling growth

This study reports a protocol for the germination and early seedling growth of Pinus peuce Gris. using zygotic embryo culture. In order to overcome seed dormancy and optimize organogenesis, the effect of nutritional, plant growth regulatory and physical factors on in vitro germination and growth of isolated mature zygotic embryos of P. peuce were investigated.Projekat ministarstva br.17301

Antimicrobial effects of carbonaceous material functionalized with silver

Carbonaceous materials as well as its form functionalized with metallic silver have been prepared by hydrothermal carbonization of fructose. Results are presented to show that nanostructured silver was obtained through the functionalization process. The carbonaceous materials were characterized by: nitrogen adsorption/desorption measurement, XRD, SEM/EDS and FTIR. Samples functionalized with silver were analyzed by: XRD and SEM/EDS. The XRD analysis showed that the carbonaceous materials functionalized with silver by hydrothermal carbonization process were successfully performed. Size of silver particles was found to be approximately 32 nm, indicating formation of nanostructure. All samples were tested as an antimicrobial agent for water disinfection. Presence of nanostructured silver in the sample containing 1 mg/mL carbonaceous materials significantly decreased the number of CFU (dCFU = 97.33 %) if compared to the same sample containing the same amount of carbonaceous materials but without of silver (dCFU 65.33 %)

Preparation and Characterization of Active Carbon Microspheres Obtained from Fructose and Adsorption Application

A carbon-rich solid product has been synthesized by hydrothermal treatment from fructose with phosphoric acid (H3 PO4 ) at temperature of 250°C and pH value of 0.65. The concentration of the precursor was constant, i.e. 2M of fructose in form of aqueous solution. The formation of the carbon-rich solid material through the hydrothermal carbonization of fructose is the consequence of dehydration reactions. Obtained carbon material is made of spherical micrometer-sized particles with the diameter in the 4-7 μm. The structure and surface chemical properties of obtained material were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectra. Investigation of surface area was determined by gravimetric McBain method where adsorption and desorption isotherms of N2 were measured on carbon material at -196 °C. Adsorption of Methylene Blue (MB) onto prepared carbon material were conducted by changing concentration of MB from 200-500 mg/dm 3 from aqueous solutions of investigated dye. Kinetic results were determined by a pseudo second-order equation.IX Serbian Ceramic Society Conference - Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts; September 20-21, 2021; Belgrad

Preparation and Characterization Of Active Carbon Microspheres Obtained From Fructose And Adsorption Application

Carbon material with active surface properties have been synthesized by hydrothermal method from fructose using 40% and 80% phosphoric acid (H3 PO4 ) solution, at temperature of 260°C and fructose concentration of 2M. The aim of this investigation was active carbon material synthesis which is completed by one step reaction, which was not the case in our previous works. Thus, compared with other samples from our works, this way is more economic and faster since both reaction of carbonization and activation was finished in one step. The hydrothermal process, in general, includes heat treatment of carbohydrate solutions under autogenous pressure at low temperatures (150–260 °C). Obtained solid carbon material has uniform morphology, amorphous structure and high content of oxygen functional groups. Prepared active carbon material is made up of spherical microsphere particles with the diameter in the range of 0.6-2.7 μm. The morphology and surface properties of obtained material were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectra. Adsorption and desorption isotherms of N2 were measured on carbon containing material at -196 °C using the gravimetric McBain method. Adsorption from aqueous solutions of Methylene Blue (MB) onto prepared carbon material was conducted by changing concentration of MB from 200-500mg/dm3 . The best fit of the kinetic results was achieved by a pseudo second-order equation. Also, this nature of material is applicable in other systems regarding environmental protection and dye pollution prevention.IX Serbian Ceramic Society Conference - Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts; September 20-21, 2021; Belgrad

ADSORPTION OF METHYLENE BLUE DYE ON ACTIVATED CARBON OBTAINED FROM THE FRUIT OF PLANE TREES

The fruit of plane trees is used to obtain the powdered activated carbon. As the activating agent is used in the preparation of concentrated phosphoric acid. Completed the equilibrium adsorption of cationic methylene blue dye in the synthesized material. These results were fitted with three adsorption equilibrium model. The experimental results were analyzed by the Langmuir isotherm, Freundlich isotherm in the Temkin isotherm. The best fit of the experimental results with theoretical models is obtained in the case of Langmuir's equilibrium models. According to the Langmuir model, achieved the best adsorption capacity of the adsorbent color which is 354.60 mg g-1 when activated carbon treated with NaOH