Valorization of cobalt from the cathode material of spent lithium-ion batteries

U doktorskoj disertaciji ispitivana je mogućnost valorizacije kobalta iz istrošenih litijumjonskih baterija. Detaljno je proučen i razvijen svaki stadijum u procesu reciklaže baterija. Primenom TGA analize određena je vrednost optimalne temperature za odvajanje katodnog materijala od aluminijumske folije. Metode ICP-OES i XRD korišćene su za razvoj metodologije za klasifikaciju litijum-jonskih baterija na osnovu hemijskog sastava katodnog materijala. Razvijena je i aparatura za praćenje koncentracije kobalta u lužnim rastvorima, uz dobijanje preciznih informacija o valentnom stanju jona kobalta. Utvrđeni su optimalni uslovi luženja katodnog materijala u atmosferi azota, kiseonika i sumpor-dioksida. Sprovedena kinetička analiza procesa luženja katodnog materijala u tri ispitivana sistema za luženje, ukazala je da se rastvaranje katodnog materijala u atmosferi N2, O2 i u prisustvu redukcionog sredstva, odvija u jednom stadijumu. U reakciji rastvaranja katodnog materijala u atmosferi N2 i O2 nastaje mešoviti oksid Co3O4. Nagrađeni oksid kobalta formira teško rastvorni, porozni sloj, koji sa vremenom raste. Narastajući sloj Co3O4 sprečava transport jona Li i Co iz katodnog materijala, kao i transport agensa za luženje do reakcione površine. Posledice navedenog su manje vrednosti stepena izluženja kobalta. Za razliku od sistema luženja katodnog materijala u atmosferi O2 i N2, mehanizam izluženja Co u atmosferi SO2 odvija se u jednom stadijumu, bez formiranja čvrstog Co3O4 kao produkta reakcije luženja. Snimljeni ciklični voltagrami ukazali su da dobijeni lužni rastvori nisu pogodni za elektrolitičko taloženje kobalta, i da je za veći stepen efikasnosti procesa neophodno povećati pH i električnu provodljivost rastvora.In this doctoral dissertation, the possibility of valorization of cobalt from spent lithium-ion batteries was investigated. Each stage in the battery recycling process was studied and developed in detail. Using TGA analysis, the optimal temperature value for separation of the cathode material from the aluminium foil was determined. The ICP-OES and XRD methods were used to develop the methodology for classification of lithium-ion batteries based on the chemical composition of the cathode material. In addition, the apparatus for monitoring cobalt concentration in the leach solutions was developed, providing precise information on the valence state of cobalt ions. Optimal conditions for the cathode material leaching process in the atmospheres of nitrogen, oxygen and sulfur-dioxide were determined. The performed kinetic analysis of cathode material leaching in the three investigated leaching systems indicates that dissolution of the cathode material in the N2 and O2 atmospheres and in the presence of a reducing agent, proceeds in one stage. The dissolution reaction of the cathode material in N2 and O2 atmospheres results in the formation of Co3O4 mixed oxide. This oxide forms a hardly soluble porous layer which grows with time. The growing Co3O4 layer prevents the transport of Li and Co ions from the cathode material, as well as the transport of the leaching agents to the reaction surface. Consequently, the values of the degree of cobalt leaching are lower. Unlike the cathode material leaching in O2 and N2 atmosphere, the leaching mechanism of Co in SO2 atmosphere occurs in one stage, without the formation of solid Co3O4 as the product of the leaching reaction. The recorded cyclic voltagrams indicate that the obtained leach solutions are not convenient for electrolytic deposition of cobalt and that in order to achieve higher process efficiency it is necessary to increase the pH value and electrical conductivity of the solution

Kultivisanje, održavanje i primena Caenorhabditis elegans u biomedicinskim istraživanjima

Caenorhabditis elegans je neparazitska nematoda koja živi u zemljištu. Prvi podaci o primeni C. elegans u eksperimentalne svrhe potiču još iz 1965. kada je Sidni Brener, južnoafrički biolog, proučavao ponašanje i razvoj životinja (naročito neuralni razvoj) na ovoj nematodi. Nedugo zatim C. elegans je postao jedan od napopularnijih eksperimentalnih modela u biomedoicinskim istraživanjima. Tome u prilog govori činjenica da su do danas tri Nobelove nagrade dodeljene naučnicima koji su istraživanja upravo radili na C. elegans, a pored toga, dobijena su i mnoga druga značajna otkrića u različitim oblastima biomedicine. Veoma brz i kratak životni ciklus (3-5 dana), velikog broja potomaka i lako kultivisanja u laboratorijskim uslovima neke su od glavnih prednosti C. elegans. Za kultivaciju ove nematode koristi se podloga za rast nematoda (Nematode Growth Median) u koju se dodaje E. coli OP 50 kojom se C. elegans hrani. Postoje dva pola: samooplodni hermafroditi i mužjaci. U najvećem broju odrasli C. elegans su 1 mm dugi hermafroditi sa reproduktivnim ciklusom od 2,5-4 dana na sobnoj temperaturi i srednjim životnim vekom od približno 18-20 dana na 20°C. Nakon izleganja, C. elegans može ili da se razvije direktno kroz četiri stadijuma larve (L1-L4) ili da nastavi sa stadijumom „dauer“ larve, umesto stadijuma L3. Faza „dauer“ larve je razvojno zaustavljena faza disperzije koja se koristi za preživljavanje u nepovoljnim uslovima. Kada se nepovoljni uslovi povuku, C. elegans se može oporaviti i razviti u stadijum larve L4. C. elegans se intenzivno koristi u ispitivanju apoptoze, transdukcije, starenja, zelenog fluorescentnog proteina i njegove uloge u ekspresiji gena, ispitivanju jonskih kanala, testiranju modela bolesti, ispitivanju lekova i dr. U našoj laboratoriji C. elegans koristimo u ispitivanjima mehanizma dejstva antinematodnih lekova i mehanizmima razvoja rezistencije nematoda

Lyophilization as a method for pathogens long term preservation

Lyophilization (freeze-drying) is one of the most suitable methods used for a long term preservation of pathogens. The aim of this paper was the application of lyophilization for storage of three significant plant pathogens: Fusarium graminearum, Helminthosporium gramineum, and Pseudomonas syringae pv. gylicinea, respectively. The plant material was collected continuously (during a four year period 2002-2006), depending on a plant development stage, from different localities in Vojvodina. Pathogens were isolated from diseased parts with characteristic symptoms, and placed on nutritive media specific for a certain pathogen, using standard phytopathological methods. Lyophilization was carried out in marked and coded ampoules by freezing and drying of pathogen suspension and nutritive medium. Revitalization of lyophilized isolates was done after four days. High percentage of revitalization was characteristic for all studied isolates, and it ranged from 85-92%, confirming that lyophilized pathogens would be capable of keeping viability for a long time in the collection. Besides above mentioned pathogens, there were 200 isolates in the collection, originating mostly from field and vegetable crops. Each isolate that was put into the Collection, was followed by all the necessary data such as: name of the pathogen, number of isolates, locality, host plant year of isolation, name of the researcher and other relevant data

TRPV1: A Promising drug target for the treatment of various conditions

Nobelova nagrada za fiziologiju i medicinu za 2021. dodeljena je naučnicima koji su identifikovali receptore za temperaturu i dodir. Da bi sproveli ovo ispitivanje, istraživači su koristili kapsaicin, jedinjenje koje čili paprici daje toplotu, kako bi otkrili receptore koji omogućavaju ljudima da osete “gorući” ukus čilija. Pokazano je da se transient receptor potential vanilloid 1 (TRPV1), koji predstavlja jonski kanal prisutan na senzornim neuronima, otvara u prisustvu kapsaicina ili toplote, propuštajući naelektrisane jone kalcijuma u ćeliju. Takav priliv kalcijuma pokreće električne signale koji se šalju u mozak da upozore na toplotu. TRPV1 se nalazi u somatosenzornom sistemu i služi kao multimodalni senzor različitih štetnih stimulusa. Brojne farmakološke i genetičke studije su potvrdile TRPV1 kao terapeutsku metu u nekoliko pretkliničkih modela hroničnog bola, uključujući maligni, neuropatski, postoperativni i mišićno-skeletni bol. Pored toga, ekspresija TRPV1 se takođe primećuje na ne-neuronskim lokalizacijama, kao što su epitel bešike i pluća, ćelije kohlee u uhu. Stoga, lekovi koji mogu da modulišu aktivnost kanala TRPV1 mogu biti korisni za lečenje različitih stanja u rasponu od hroničnog bola do gubitka sluha. Iako je utvrđeno da antagonisti TRPV1 mogu predstavljati važan dodatak terapiji bola, njihova klinička upotreba je i dalje ograničena značajnim neželjenim efektima, kao što je hipertermija. U ovom radu ćemo opisati najvažnije uloge TRPV1 u fiziološkim i patofiziološkim procesima i predstaviti najperspektivnije lekove koji deluju preko TRPV1.The 2021. Nobel Prize in Physiology or Medicine was awarded to scientists who have identified receptors for temperature and touch. In order to conduct this examination, researchers used capsaicin, the compound that gives chili peppers their heat, to discover receptor proteins that allow people to feel chili’s burn. It is shown that transient receptor potential vanilloid 1 (TRPV1), which represents an ion channel present on sensory neurons, opens when it encounters capsaicin or heat, allowing charged calcium ions into the cell. That flood of calcium triggers electrical signals that are sent to the brain to warn of heat. TRPV1 is found in the somatosensory system and serves as a multimodal sensor of different noxious stimuli. Numerous pharmacological and genetic studies have validated TRPV1 as a therapeutic target in several preclinical models of chronic pain, including cancer, neuropathic, postoperative and musculoskeletal pain. Additionally, expression of TRPV1 is also observed in non-neuronal sites such as the epithelium of bladder and lungs, cells of the cochlea. Therefore, drugs which could modulate TRPV1 channel activity could be useful for the treatment of conditions ranging from chronic pain to hearing loss. While antagonists of TRPV1 were found to be a valuable addition to therapy of pain, their clinical use has still been limited by significant side effects, such as hyperthermia. In this review, we will describe the most important roles of TRPV1 in physiological and pathophysiological processes and present the most promising TRPV1-targeted drugs

Occurence of Fusarium equiseti Corda (Saccardo) as causal agent of seed rot of Hyssopus officinalis L.

Hyssop (Hyssopus officinalis L.) is a perennial polymorphous plant species with essential oil mainly accumulated in the flowers and leaves. It is grown in Serbia for the needs of pharmaceutical companies and tea production, because of its quality and chemical composition. During a routine quality control of hyssop seeds collected from Rumenka (Vojvodina Province), in 2018, fungal infection followed by seed rot was noticed on an average of 22%. Infected seeds were covered with white mycelium followed with violet pigmentation occurring under the seeds. The presence of Fusarium spp. was confirmed with microscopic observation. Isolation was done aseptically by arranging infected seeds onto surface of potato dextrose agar (PDA), and incubated at 25 °C with a 12-h photoperiod (Mathur and Kongsdall, 2003). After seven days, 12 Fusarium spp. isolates were designated as JBL 4003/1 - 4003/12. Pathogenicity test was performed in vitro using a modified agar slant method in the test tube with PDA amended. After 10 days, fungal mycelia of tested isolates caused seed rot and seedling decay, like naturally infected hyssop seeds. All isolates were re-isolated and sub-cultured on Potato Dextrose Agar (PDA) and Carnation Leaf Agar (CLA) using a hyphal tip transfer technique, fulfilling Koch's postulates. Isolate JBL 4003/1 was distinguished based on pathogenicity and cultural characteristics. It caused seed rot after four days, on PDA colony was fast growing reaching 6-8 cm in diam. in five days, forming abundant, whitish to peach aerial mycelium followed with beige to light brown pigmentation in agar

Pharmacotherapy of Rare Diseases in Serbia: The Current State of Art

Rare diseases affect less than 1 in 2000 or 5 in 10,000 people by definition. Most of those diseases have genetic basis (80% of cases) and first symptoms appear in early childhood (50% of cases). Most of these diseases are chronic and degenerative and pharmacotherapy is not available for many of them. Until today, there are more than 7000 rare diseases. In Serbia, the problem of diagnosis and pharmacotherapy of rare diseases is currently under public scrutiny. Patients who suffer from rare diseases in Serbia face many challenges in terms of awareness, timely diagnosis, and adequate treatment. These people are often misdiagnosed or the diagnosis is delayed due to several problems: lack of awareness among medical professionals, lack of expertise, unavailability and/or high costs of diagnostic tests, etc. According to the National Organization of Patients with Rare Diseases in Serbia (NORBS), many diagnostic procedures have to be conducted abroad and the process comprises many difficulties: high costs, travel expenses, or transportation of biological material. Although national legislation ensures the availability of drugs for those diseases, pharmacotherapy is faced with many problems. In this work, we aim to show that improvement of the knowledge regarding rare diseases among both professionals and patients represents a crucial step for enhancement of perspectives for those patients in our community

PVDF-HFP/NKBT composite dielectrics: Perovskite particles induce the appearance of an additional dielectric relaxation process in ferroelectric polymer matrix

Na0.25K0.25Bi0.5TiO3 (NKBT) perovskite particles are synthesized by solid-state method and used as a filler for polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) co-polymer. X-ray diffraction analysis of NKBT powders shows that the particles have a rhombohedral perovskite crystal structure (R3c symmetry). Raman spectroscopy reveals that the co-polymer crystallizes predominantly into the mixture of polar beta- and gamma-crystals, while there is also a contribution of the non-polar a-crystal phase. The introduction of the NKBT into the PVDF-HFP results with an increase in effective dielectric permittivity and this effect depends on the inorganic content in the composite. The most interesting result of the present study is that the introduction of NKBT particles induces the appearance of an additional transition peak in the dielectric spectra of the co-polymer matrix. At the fixed frequency of similar to 2 kHz, the observed process appears at similar to 10 degrees C (about 45 degrees above the glass transition temperature) and its magnitude strongly depends on the amount of the NKBT in the composite. Dielectric spectroscopy measurements of the composites are carried out in the wide range of frequencies (from 0.1 Hz to 1 MHz) and temperatures (from -100 to 100 degrees C). They reveal that the novel process can be clearly distinguished in the frequency range between 160 Hz and similar to 50 kHz

Pharmacological effects of monoterpene carveol on the neuromuscular system of nematodes and mammals

The control of parasitic nematode infections relies mostly on anthelmintics. The potential pharmacotherapeutic application of phytochemicals, in order to overcome parasite resistance and enhance the effect of existing drugs, is becoming increasingly important. The antinematodal effects of carveol was tested on the free-living nematode Caenorhabditis elegans and the neuromuscular preparation of the parasitic nematode Ascaris suum. Carveol caused spastic and geraniol atonic paralysis in C. elegans. In A. suum carveol potentiated contractions induced by acetylcholine (ACh) and this effect was confirmed with two-electrode voltage-clamp electrophysiology on the A. suum nicotinic acetylcholine receptor expressed in Xenopus oocytes. However, potentiating effect of carveol on ACh-induced contractions was partially sensitive to atropine, indicates a dominant nicotine effect but also the involvement of some muscarinic structures. The effects of carveol on the neuromuscular system of mammals are also specific. In micromolar concentrations, carveol acts as a non-competitive ACh antagonist on ileum contractions. Unlike atropine, it does not change the EC50 of ACh but reduces the amplitude of contractions. Carveol caused an increase in Electrical Field Stimulation-evoked contractions of the isolated rat diaphragm, but at higher concentrations it caused an inhibition. Also, carveol neutralized the mecamylamine-induced tetanic fade, indicating a possibly different pre-and post-synaptic action at the neuromuscular junction

Actual contamination of the Danube and Sava Rivers at Belgrade (2013)

This study was focussed on a comprehensive investigation on the state of pollution of the Danube and Sava Rivers in the region of Belgrade. Different complementary analytical approaches were employed covering both i) organic contaminants in the river water by target analyses of hormones and neonicotinoids as well as non-target screening analyses and ii) heavy metals in the sediments. Finally, some common water quality parameters were analysed. The overall state of pollution is on a moderate level. Bulk parameters did not reveal any unusual observations. Moreover, quantification of preselected organic contaminants did not indicate to elevated pollution. More significant contaminations were registered for chromium, nickel, zinc and partially copper in sediments with values above the target values according to Serbian regulations. Lastly, non-target screening analysis revealed a wider spectrum of organic contaminants comprising pharmaceuticals, technical additives, personal care products and pesticides. The study presented a comprehensive view on the state of pollution of the Sava and Danube Rivers and is the base for setting up further monitoring programs. As a superior outcome, it was illustrated how different chemical analyses can result in different assessments of the river quality. A comparison of target and non-target analyses pointed to potential misinterpretation of the real state of pollution

Nove NS sorte povrtarskih biljnih vrsta

Povrće je važan deo ljudske ishrane jer ono prvenstveno sadrži materije korisne za ljudsko zdravlje kao što su: vitamini, minerali, biljna vlakna, antioksidansi, organske kiseline i dr. U svetu je poznato oko hiljadu vrsta povrća, od kojih se gaji oko 150, a najširu upotrebu ima 30-50 vrsta, koliko je zastupljeno u ishrani u Srbiji (Gvozdanovic-Varga i sar., 2016). U Institutu za ratarstvo i povrtarstvo Novi Sad do sada je stvoreno više od 50 sorti povrća priznatih u zemlji i delom u inostranstvu. Sortiment povrća Odeljenja za povrtarske i alternativne biljne vrste čine nove sorte povrća, kao i odomaćene sorte, te se proizvodi seme 27 povrtarskih vrsta i 10 vrsta cveća. Pored rada na novim sortama povrća koje se odlikuju visokim prinosom, vodilo se računa da sorte svojim izgledom i ukusom zadovoljavaju zahteve probirljivog tržišta i da su prilagođene našim agroklimatskim uslovima (Gvozdenovic i sar., 2008). Zadatak ovog rada je da se prikažu karakteristike novopriznatih sorti povrća, koje su dobijene kao rezultat višegodišnjeg rada, u cilju zadovoljenja potreba proizvođača i potrošača za novim, atraktivnim i kvalitetnim sortama povrtarskih vrsta