Крајем 2021. године објављена је студија Ђорђа Деспића о критичко-есејистичком опусу великог српског песника, есејисте, критичара и антологичара Миодрага Павловића (1928–2014) под називом Тумач и ...песма: есејистика Миодрага Павловића, која представља незнатно измењену докторску дисертацију проф. Деспића одбрањену 2013. Ова студија је у октобру 2022. године овенчана и наградом „Ђорђе Јовановић“ за најбољу монографску студију објављену у претходној години, те се може рећи да та чињеница особито препоручује посвећивање пажње овој студији. Овим делод Деспић наставља проучавање различитих аспеката стваралаштва Миодрага Павловића, започетог књигом Порекло песме (Агора, 2008) о потенцијалима интертекстуалности у поезији овог песника, што је представљало јединствену такву студију у дотадашњој српској науци о књижевности.
Annual production of the sunflower seed in Serbia is between 650,000-720,000
tons. Most of this amount is used in vegetable oil industry. Abundant
by-products from this processing are sunflower seed ...husks. Husks are usually
incinerated by vegetable oil producers in order to obtain energy, used as an
animal feed, or, unfortunately, landed up at some landfills. In order to
promote new, added value for this abundant, renewable resource, the
investigation presented in this paper was conducted. For that purpose,
adsorption of Cu(II) ions from synthetic solution by unmodified sunflower
seed husks was examined. ATR-FTIR was used to identify functional groups as
potential active sites for Cu(II) sorption. Zeta potential values were
determined to reveal the surface charge, while the cation exchange capacity
(CEC) was determined to reveal the amount of exchangeable ions on its
surface. ATR-FTIR analysis revealed the presence of specific functional
groups (hydroxyl, carboxyl, carbonyl, and amine) responsible for removal of
Cu(II) ions. The total CEC of sunflower husk is 47.74 meq/100g and Ca(II)
and Mg(II) ions are in dominant exchangeable positions. The study of
ion-exchange mechanism involvement was done and results confirmed that this
mechanism is not the only mechanism which is involved in copper sorption.
Also, the results show that the Cu(II) ions have preference for Mg(II) ions
substitution. Sorption experiments were conducted in batch system. The
effect of operating parameters (pH, contact time, initial concentration of
Cu(II) ions and adsorbent dosage) on the adsorption capacity were
investigated. The obtained experimental data were fitted by Langmuir and
Freundlich isotherm models. The maximum adsorption capacity for Cu(II) ions
calculated from Langmuir adsorption isotherm was 34.89 mg/g which is 15 to
35% higher than the capacity that other researchers reported previously for
the same material and pollutant. These results are suggesting that sunflower
seed husks have a potential to be applied as an effective adsorbent of
copper ions from contaminated waters.
The paper illuminates some of the principles by which Helmut Newton's photographic poetics functions. It is examined from the perspectives of recent art history, feminist critique and psychoanalytic ...theory. His photographs came to a standstill not far from pornography, yet they stayed within the jet-set community, reflecting at the same time the sexual revolution in the 60s and 70s of the twentieth century and the rising of the fashion and film industries and other Western emancipatory movements. Newton's obscure photojournalism provoked conventions, presenting the female body as a fetish and object of erotic pleasure, affirming, nonetheless, a new feminine self-consciousness and freedom. Thus, he constituted modern eroticism by connecting fetishism, voyeurism and sadomasochism, creating a provocative hybrid photography that embraced fashion, eroticism and portrait, hence documenting, in highly stylistic manner, the decadency and eccentricity of the lifestyle of the rich.
The study is focused on the determination of the most effective chemical leaching process for the simultaneous demineralization/deashing and desulfurization of subbituminous coal from the Bogovina ...Basin. Coal was treated for 30 min, at different temperatures, using variable concentrations of hydrochloric, nitric, acetic and citric acids; hydrogen peroxide, mixture of hydrogen peroxide and nitric acid (pH 2), as well as by the stepwise leaching process (nitric acid + mixture of hydrogen peroxide and nitric acid, pH 2). The changes in mineral composition, caused by the chemical leaching, are followed using X-ray diffraction, whereas alterations of coal organic matter are tracked by Fourier-transform infrared spectroscopy and the content of fixed carbon. Inorganic acid leaching, regardless of the temperature and acid concentration, enabled the successful deashing of coal, whereas the percent of desulfurization was insufficient. The organic acid leaching was not satisfactory for both, deashing and desulfurization. Leaching by H2O2 and H2O2/HNO3 mixture (pH 2) resulted in moderate desulfurization, but the ash reduction was low. The most suitable method for the simultaneous effective ash (78 wt.%) and the sulfur (66 wt. %) removal from Bogovina coal is the two-step leaching, combining 10 vol. % HNO3 and mixture of 35 vol. % H2O2/10 vol. % HNO3 of pH 2 at 60?C.
Titanium (Ti) is widely used in medical and dental implants. Calcium phosphate (CPs) coatings enhance Ti implants’ osteoinductive properties, and additives further improve these coatings. Recently, a ...nano amorphous calcium phosphate (nACP) coating decorated with chitosan oligolactate (ChOL) and selenium (Se) showed immunomodulatory effects. This study investigates the surface morphology, composition, bioactivity, mechanical properties, and Se-release mechanism of the nACP@ChOL-Se hybrid coating on Ti substrates. Amorphous calcium phosphate (ACP) was synthesized, and the nACP@ChOL-Se hybrid coating was deposited on Ti substrates using in situ anaphoretic deposition. Physico-chemical characterization was used to analyze the surface of the coating (scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy). The distribution of Se within the coating was examined with energy-dispersive X-ray spectroscopy (EDS). Bioactivity was evaluated in simulated body fluid (SBF), and adhesion was tested using a scratch test method. In vitro testing determined the release mechanism of Se. SEM images illustrated the surface morphology, while AFM provided a detailed analysis of surface roughness. XRD analysis revealed structural and phase composition, and EDS confirmed Se distribution within the coating. The coating exhibited bioactivity in SBF and showed good adhesion according to the scratch test. In vitro testing uncovered the release mechanism of Se from the coating. This study successfully characterized the surface morphology, composition, bioactivity, and Se-release mechanism of the nACP@ChOL-Se hybrid coating on Ti substrates, offering insights for developing immunomodulatory coatings for medical and dental applications.
Graphical Abstract
Electrophoretic deposition (EPD) occurs as a cataphoretic deposition ? the coating is deposited on the cathode, and anaphoretic deposition ? the coating is deposited on the anode. The primary purpose ...of EPD is to obtain compact and uniform organic/inorganic coatings of the desired thickness and adhesion on metal surfaces by applying an electric field to the particles of coating precursor. EPD basic principles for coatings deposition concerning fundamental explanations and considerations of practical parameters of the process are presented. Cataphoretic deposition has become popular because it can apply organic coatings to complex structures that are otherwise very difficult to coat. These coatings were found to improve the characteristics of the substrate, such as biocompatibility, appearance and resistance to the corrosion processes. The key EPD parameters are composition, pH value and viscosity of deposition medium, as well as zeta potential of the particles, electric field strength, etc. A special survey is given to the process of anaphoretic deposition, which is relatively new, and its advantages over cataphoretic deposition are discussed. Through the process of joint anaphoresis/substrate anodization process, the surface of the substrate is simultaneously anodized and modified by incorporation of the foreign particles into the anodic layer. The coatings of mixed composition of better adhesion and corrosion resistance with respect to cataphoretically- deposited coatings are obtained as result.
Abstract The present study compared the photothermal anticancer activity of near-infrared (NIR)-excited graphene nanoparticles and carbon nanotubes (CNT). Despite lower NIR-absorbing capacity, ...suspension of polyvinylpyrrolidone-coated graphene sheets exposed to NIR radiation (808 nm, 2 W/cm2 ) generated more heat than DNA or sodium dodecylbenzenesulfonate-solubilized single-wall CNT under the same conditions. Accordingly, graphene nanoparticles performed significantly better than CNT in inducing photothermal death of U251 human glioma cells in vitro. The superior photothermal sensitivity of graphene sheets could be largely explained by their better dispersivity, which has been supported by a simple calculation taking into account thermodynamic, optical and geometrical properties of the two type of carbon nanoparticles. The mechanisms of graphene-mediated photothermal killing of cancer cells apparently involved oxidative stress and mitochondrial membrane depolarization resulting in mixed apoptotic and necrotic cell death characterized by caspase activation/DNA fragmentation and cell membrane damage, respectively.
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