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The preferred orientation of electrodeposited dendrites of lead, tin and zinc
No full textMorphology and crystal orientation of electrolytically produced dendrites of lead, tin, and zinc have been investigated with the aim of establishing any correlation between them. These three metals belong to the same group of metals from an electrochemical point of view (the group of normal metals), but to various types of crystal lattice (Pb-the facecentered cubic type, Sn-the body-centered tetragonal type, and Zn-the hexagonal closed pack type). Pb, Sn and Zn dendrites were produced potentiostatically using the corresponding hydroxide electrolytes and characterized by scanning electron microscopy (morphology) and X-ray diffraction (crystal orientation) techniques. The preferred orientation of the dendritic particles was determined by applying a method based on a comparison of the peak intensity ratios. The fern-like dendrites of various degrees of branchy were obtained by the processes of electrolysis, and regardless of the type of crystal lattice, they exhibited the strong preferred orientation in crystal planes with the lowest surface energy. Based on the performed analysis, a strong correlation between the morphology and the crystal structure of dendrites belonging to the group of normal metals has been established. It is concluded that electrochemical parameters characterized by the high values of the exchange current density (the fast electrochemical processes) prevailed over crystallographic characteristics of metals manifested by the belonging to a determined type of crystal lattice
Optically controlled flexodomains in chiral nematics
No full textPeriodic flexoelectric domains (FDs) stimulated by both electric and optical fields were examined in a photosensitive chiral nematic liquid
crystal. It was observed that the optical field is an excellent candidate to modulate the morphology and electric threshold voltage of FDs, by
either an optically induced surface effect through photo-alignment or an optically induced bulk effect through the optical control of chirality. With preset spatial patterns of the optical field, proof-of-concept prototypes of ring-shaped and fan-shaped gratings were constructed,
which can be used in encoders to measure the angle directly and precisely
Evaluation of Adhesion Properties of Electrodeposited Copper Thin Films: Theoretical and Experimental Approach
No full textThe adhesion of copper thin films galvanostatically electrodeposited on Cu
cathodes from electrolytes without or with the addition of various additives, such as
chloride ions, polyethylene glycol 6000 (PEG 6000), and 3–mercapto–1–propanesulfonic
acid, has been investigated. Morphological and structural analyses of synthesized films
were performed using the SEM, AFM, and XRD methods, while the adhesion of the films
was examined by applying the theoretical Chen–Gao (C–G) composite hardness model
using results from Vickers microindentation, a bidirectional bending test, and a scratch-tape
adhesion test. The morphologies of the films were either very smooth, with mirror-like
brightness, obtained from the electrolyte containing all three additives, or microcrystalline,
with different grain sizes, obtained from other electrolytes. The best adhesion was observed
in the fine-grained film with numerous boundaries among grains, obtained with the
addition of chloride ions and PEG 6000, while the mirror-bright film obtained with a
combination of all three additives showed the worst adhesion. The boundaries among
grains represented barriers that decreased the depth of penetration during microindentation
and, consequently, increased the hardness and enhanced the adhesion of the film. The
size of the grains—and hence, the number of grain boundaries—was regulated by the
composition of the electrolytes achieved by the addition of additives. Good agreement was
observed among the various methods used for the estimation of the adhesion properties of
Cu films
Effects of buckwheat and millet flour addition on the antioxidant potential of wheat flour and rheological properties of the dough
No full textIn this work, the antioxidant properties of three types of flour (wheat, buckwheat and millet
flour) and rheological properties of three types of dough were investigated: wheat flour dough,
dough obtained from a mixture of 50 wt.% wheat flour and 50 wt.% buckwheat flour and dough
obtained from a mixture of 50 wt.% wheat flour and 50 wt.% millet flour. Polyphenol content
and antioxidant tests have shown that buckwheat flour is superior to wheat and millet flour.
The antioxidant activity expressed by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging
activity did not correlate with the content of polyphenols, which is a consequence of the
presence of tannins and phytic acid in millet flour. Determination of rheological properties was
performed by a universal dough characterizer. The substitution of wheat flour with buckwheat
and millet flour leads to a weakening of the protein structure. Furthermore, the addition of
buckwheat or millet flour reduces the rate of gelatinization and viscosity and has a positive
effect on the reduction of retrogradation. The combination of these two types of flour with
wheat flour can reduce the aging of bakery products.U ovom radu su ispitivana antioksidativna svojstva tri vrste brašna (pšeničnog, heljdinog I brašna od prosa)
i reološka svojstva tri vrste testa: testa od pšeničnog brašna, testa od smeše 50 mas.% pšeničnog brašna/
50 mas.% heljdinog brašna i 50 mas.% pšeničnog brašna/ 50 mas.% brašna od prosa. Sadržaj polifenola i
antioksidativna ispitivanja su pokazala da je brašno od heljde značajno superiornije u odnosu i na brašno
od pšenice i na brašno od prosa. Antioksidativna aktivnost izražena preko DPPH radikala nije bila u korelaciji
sa sadržajem polifenola, što je posledica prisustva tanina i fitiske kiseline u brašnu od prosa. Reološka
svojstva su ispitana pomoću univerzalnog uredjaja za karakterizaciju testa. Supstitucija dela pšeničnog
brašna brašnom od heljde i prosa dovodi do slabljenja strukture proteina. Osim toga, dodavanje heljdinog
ili brašna od prosa smanjuje brzinu želatinizacije i viskoznost, a pozitivno utiče na smanjenje retrogradacije.
Kombinacija ove dve vrste brašna sa pšeničnim brašnom može dovesti do smanjivanja brzine starenja
pekarskih proizvoda
Primena DIC metode u određivanju parametara mehanike loma na epruvetama oblika prstena sa oštrim žlebom dobijenih FDM tehnikom
No full textThis paper focuses on the evaluation of fracture mechanics parameters of thin-walled pipeline components using 3D printing and digital image correlation (DIC) techniques. The experimental study is conducted on 3D-printed polymer specimens made of PLA (polylactide acid) using the FDM (Fused Deposition Modelling) process. All specimens were tested on a universal materials testing machine, with strain measurements by the Aramis 2M system based on DIC. This setup allowed for the accurate analysis of key fracture mechanics parameters, including crack mouth opening displacement (CMOD) and crack tip opening displacement (CTOD-δ5). A new test geometry - the Pipe Ring Notched Tension (PRNT) was compared to standard single-edge notched tension (SENT) specimens and their properties were compared to provide a more realistic assessment of the mechanical behaviour of pipeline materials. This research is particularly important given the increasing use of additive manufacturing to produce functional spare parts, which are increasingly integrated into pressure-containing process equipment, highlighting the importance of accurate fracture mechanics assessment in ensuring component reliability and safety.Ovaj rad se fokusira na procenu parametara mehanike
loma komponenata tankozidnih cevovoda korišćenjem 3D
štampe i digitalne korelacije slike (DIC). Eksperimentalna
ispitivanja su sprovedena na 3D štampanim uzorcima polimera napravljenim od PLA (polilaktidne kiseline) korišćenjem FDM (Fused Deposition Modelling) procesa. Svi uzorci
su testirani na univerzalnoj mašini za ispitivanje materijala,
uz merenje deformacije pomoću sistema Aramis 2M zasnovanog na DIC-u. Ova postavka je omogućila preciznu analizu ključnih parametara mehanike loma, uključujući pomeranje otvaranja usta prsline (CMOD) i pomeranje otvaranja
vrha prsline (CTOD-5). Nova geometrija epruvete oblika
prstena sa oštrim žlebom opterećena na zatezanje (PRNT) -
upoređena je sa standardnim uzorcima sa zarezom sa
jednom ivicom (SENT) i njihova svojstva su upoređena da
bi se obezbedila realnija procena mehaničkog ponašanja
materijala cevovoda. Ovo istraživanje je posebno važno s
obzirom na sve veću upotrebu aditivne proizvodnje za proizvodnju funkcionalnih rezervnih delova, koji su sve više integrisani u procesnu opremu pod pritiskom, naglašavajući
važnost tačne procene mehanike loma u obezbeđivanju pouzdanosti i bezbednosti komponenata
Development of Bioactive Cotton, Wool, and Silk Fabrics Functionalized with Origanum vulgare L. for Healthcare and Medical Applications: An In Vivo Study
No full textThis study presents an innovative approach to developing bioactive natural fabrics for healthcare and medical applications. Methods: An ethanol extract of Origanum vulgare L. (in further text: OE), exhibiting exceptional antioxidant (100%) and antibacterial activity (>99% against E.coli and S.aureus), was employed to biofunctionalize cotton, wool, and silk fabrics. Results: All biofunctionalized fabrics demonstrated strong antioxidant activity (>99%), while antibacterial efficacy varied by fabric: cotton > 54%, wool > 99%, and silk > 89%. OE-biofunctionalized wool possessed the highest release of OE’s bioactive compounds, followed by silk and cotton, indicating substrate-dependent release behavior. This tunable fabrics’ OE release profile, along with their unique bioactivity, supports targeted applications: OE-functionalized silk for luxury or prolonged therapeutic use (skin-care textiles, post-surgical dressings, anti-aging products), cotton for disposable or short-term use (protective wipes, minor wound coverings), and wool for wound dressings. The biocompatibility and cytotoxicity of OE-biofunctionalized wool were evaluated via in vitro assays using healthy human keratinocytes and in vivo testing in Wistar albino male rats. The obtained results revealed that OE-functionalized wool significantly accelerated wound closure (97.8% by day 14), enhanced collagen synthesis (6.92 µg/mg hydroxyproline), and improved tissue and systemic antioxidant defense while reducing oxidative stress markers in skin and blood samples of rats treated with OE-biofunctionalized wool. Conclusions: OE-biofunctionalized wool demonstrates strong potential as an advanced natural solution for managing chronic wounds. Further clinical validation is recommended to confirm its performance in real-world healthcare settings. This work introduces an entirely new application of OE in textile biofunctionalization, offering alternatives for healthcare and medical textiles
MOF-derived nanoceria/graphitic carbon nitride as an efficient electrochemical modifier for guanine sensor with diffusional response
No full textThis work presents a novel approach for the electrochemical detection of guanine (GU) using a MOF-derived nanomaterial. CeBTC MOF-derived CeO2 nanoparticles, prepared by calcination and mixed with graphitic carbon nitride (g-C3N4) were structurally and electrochemically characterized and further applied in sensing of GU. XRPD, FTIR, SEM, and XPS measurements were used to study the composition, structure, and morphology of the nanoceria/g-C3N4 electrode modifier. Electrochemical impedance spectroscopy measurements and cyclic voltammetric studies indicated an improved electrocatalytic output of nanoceria/g-C3N4 modified carbon paste electrode (MOFdCeO2/g-C3N4/CPE). The optimal content of electrode modifier in CPE, experimental conditions, and analytical technique parameters were established to achieve sensitive quantification of GU. Kinetic parameters of the electrochemical reaction of GU were determined and a diffusional response at an electrochemical sensor was achieved. The linear working range of the developed square-wave voltammetric method (SWV) in Britton Robinson buffer solution pH 3.0 at MOFdCeO2/g-C3N4/CPE was recorded from 0.5 μM to 100 μM of GU, with a detection limit of 0.12 μM. The proposed guanine sensor showed good storage stability, repeatability, and selectivity, and its real sample applicability was successfully tested by quantification of guanine in spiked urine samples, with excellent accuracy and precision
Impact of Chocolate Cadmium on Vulnerable Populations in Serbia
No full textChocolate is one of the most popular and widely consumed confectionery products. However, elevated cadmium (Cd) content in this commodity threatens food safety and human health. It is crucial to monitor the presence of Cd in chocolate and to evaluate its associated health risks. This study assessed the Cd levels in milk and dark chocolates from the Serbian market (n = 155). Cadmium concentrations varied between 0.010 and 0.29 mg/kg. The obtained values were used to evaluate the hazard quotient (HQ) and cancer risk (CR). The estimated weekly intakes (EWIs) were below the tolerable limits for all samples. However, in some samples, the EWI reached 60.9% and 63.5% of the tolerable limit for toddlers and other children, respectively. No health risk was found based on the HQ. On the other hand, based on CR values, all chocolate products can be classified as posing a moderate risk. The Monte Carlo simulation indicated that toddlers and other children were more exposed to non-carcinogenic risk, whereas vegetarians, adults, pregnant women, and other children were more exposed to cancer risk. Sensitivity analysis indicates that body weight, exposure frequency, and ingestion rate are the most influential factors for non-cancer and cancer health risks
Short-Term Microwave-Assisted Peroxide Treatment for Intensified Lignin and Sugar Recovery from Corncob
No full textDespite important advancements in recent years, the use of lignocellulosic biomass in biorefineries remains rather dif-
ficult due to the low selectivity of conventional fractionation methods. New or improved technologies that can selectively
target specific fraction while preserving the integrity of both polysaccharides and lignin are of utmost importance for
expanding the variety of bio-based products and making biomass valorization more efficient. This study showed that short-
term microwave-assisted alkaline H2O2 treatment of corncob can selectively remove lignin and improve the hydrolysis
efficiency of polysaccharide fractions allowing for higher sugar recovery. A delignification of 75% and an increase of
cellulose content and surface area by 57% and 76%, respectively, were achieved by applying a 1-minute treatment under
optimized conditions. The treatment considerably improved the adsorption capacity and hydrolysis efficiency of corncob,
resulting in a yield of hexose and pentose sugars of 61.18% and 60.24%, which was 2.7-fold and 5.6-fold higher, respec-
tively, compared with untreated biomass. XRD and FTIR analyses confirmed significant structural and compositional
alterations in treated corncob caused by treatment. The purity and yield of recovered lignin suggest the potential integra-
tion of lignin extraction into corncob biorefinery, which can increase the overall efficiency of corncob processing while
contributing to the circularity and sustainability of the food system
Phytopreparations Based on Supercritical Extracts of Immortelle and Hemp Intended for Slowing Up Visible Signs of Aging and Procedure for Obtaining
No full textJedinstvenost pronalaska predstavljaju farmaceutski i kozmetički fitopreparati za topikalnu primenu na bazi superkritičnih ekstrakata smilja (Helihrysum italicum (Roth) G. Don fil., Asteraceae) i konoplje (Cannabis sativa L., Cannabaceae) koji su namenjeni za tretman zrele kože u cilju smanjenja vidljivih znakova i usporavanje biološkog procesa starenja kože. Zahvaljujući efikasnoj kombinaciji esencijalnih sastojaka za održavanje normalnih procesa u ćelijama kože i sinergističkom delovanju aktivnih principa iz okarakterisanih standardizovanih ekstrakata, tokom tretmana kože se postižu iznenađujuće efikasni i blagotvorni rezultati. Dobijeni ekstrakti i poluproizvodi na bazi ekstraktima impregniranih nosača, formulisani su u odgovarajuće farmaceutske oblike (emulgel, krem, gel-krem, pasta, masti), koji su neočekivano efikasni i jednostavni za primenu kod promena na koži i kod promena kod kojih usled dejstva slobodnih radikala dolazi do upala i ubrzanog starenja kože.Broj prijave: P-2020/1428Broj i datum rešenja o priznanju prava: 2025/4547 04.06.2025Espacenet: [https://worldwide.espacenet.com/patent/search/family/081940367/publication/RS20201428A1?q=Phytopreparations%20Based%20on%20Supercritical%20Extracts%20of%20Immortelle%20AND%20Hemp%20Intended%20for%20Slowing%20up%20Visible%20Signs%20of%20Aging%20AND%20Procedure%20for%20Obtaining