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This review paper presents a contribution to the research of free and glycosidically bound volatiles in the 2001- 2006 period obtained by work in the Department of Organic Chemistry, Faculty of Chemistry and Technology, University of Split, Croatia. Many terpene structures, phenylpropane derivatives (Fig. 6), as well as aliphatic hydrocarbons, alcohols, carbonyls, fatty acids and others were identified (Fig. 5). The chemotypes of Origanum vulgare ssp. hirtum, Artemisia absinthium and Myrtus communis were determined and some uninvestigated or insufficiently investigated plants (Micromeria juliana, Sequaoiadendron giganteum, Populus nigra, Prunus mahaleb, Ailanthus altissima and others) were analyzed. A newly developed method of co-distillation enabled isolation of unstable volatile compounds without formation of artefacts (Fig. 1). The volatile aglycones liberated by enzymatic hydrolysis of the corresponding glycosides were aliphatic and phenylpropanoic derivatives, as well as monoterpenes, sesquiterpenes and others (Fig. 7). Only partial similarity was observed in the composition of volatile aglycones and corresponding free volatiles of the same plant. Furthermore, glucosides of ubiquitous monoterpene and aliphatic alcohols and phenols were prepared by Koenigs-Knorr glucosylation (Fig. 8), by enzymatic condensation and transglucosidation from cellobiose (Fig. 11) and by direct glucosylation with FeCl3 (Fig. 13). The products were characterized by GC-MS analysis of prepared tetraacetyl glucosides. Fragment ion characteristics of the aglucone moiety were present in all mass spectra, along with the fragments obtained from acetylated glucose (Fig. 12 and Fig. 14). Acetylated glucosides were separable on the HP-101 column, Fig. 9 (even diastereomeric tetraacetyl ß-glucosides of enantiomeric alcohols, Fig. 10). U radu je prikazan doprinos istraživanju slobodnih i glikozidno vezanih isparljivih spojeva u razdoblju 2001. - 2006. koji je ostvaren radom u Zavodu za organsku kemiju Kemijsko-tehnološkog fakulteta, Sveučilište u Splitu. Identificirane su mnoge terpenske strukture, fenilpropanski derivati, kao i alifatski ugljikovodici, alkoholi, karbonili, masne kiseline i dr. Aglikoni oslobođeni enzimskom hidrolizom glikozida isparljivih spojeva bili su alifatski, fenilpropanski derivati, monoterpeni, seskviterpeni i dr. Nadalje, sintetizirani su glukozidi čestih monoterpenskih i alifatskih alkohola, te fenola (Koenigs-Knorrova glukozilacija, izravna glukozilacija uz FeCl3, enzimska kondenzacija i transglukozilacija iz celobioze).

The seeds of the castor oil plant (Ricinus communis L.) are commonly used for obtaining castor oil that has various use in several industries, such as chemical, pharmaceutical, agricultural, and other industrial sectors. It is utilised for the production of care products, such as soaps and shampoo, lubricants, plastics, etc. Previous research has shown the benefits of using castor oil as a biodiesel and a renewable energy source. The aim of this work was to determine the physical and chemical properties of castor oil. Physical and chemical properties of selected sample of castor oil were analysed according to standard analytical methods for fats and oils. The results of analysis showed that castor oil, due to its physical and chemical properties, has a potential and relevance in cosmetic and pharmaceutical application. It can be used as raw material in different formulations, as well as for production of valuable co-products, such as glycerol. Sjemenke biljke ricinusa (Ricinus communis L.) obično se upotrebljavaju za dobivanje ricinusova ulja, koje ima različitu primjenu u nekoliko industrija, kao što su kemijska, farmaceutska, poljoprivredna i druge industrijske grane. Upotrebljava se za proizvodnju sredstava za njegu, kao što su sapuni i šamponi, lubrikanti, plastika itd. Prethodna istraživanja pokazala su prednosti uporabe ricinusova ulja kao biodizela i obnovljivog izvora energije. Cilj ovog rada bio je odrediti fizička i kemijska svojstva ricinusova ulja. Fizička i kemijska svojstva odabranog uzorka ricinusova ulja analizirana su prema standardnim analitičkim metodama za masti i ulja. Rezultati analize pokazali su da ricinusovo ulje zbog svojih fizičkih i kemijskih svojstava ima potencijal i značaj u kozmetičkoj i farmaceutskoj primjeni. Može se upotrebljavati kao sirovina u različitim formulacijama, kao i za proizvodnju vrijednih nusproizvoda, poput glicerola.

Cilj ovog rada bio je razviti tri metode temeljene na umjetnoj inteligenciji za modeliranje trostruke adsorpcije iona teških metala {Pb2+, Hg2+, Cd2+, Cu2+, Zn2+, Ni2+, Cr4+} na različitim adsorbatima {aktivni ugljen, kitozan, danski treset, treset Heilongjiang, ugljik glave suncokreta i ugljik stabljike suncokreta). Rezultati pokazuju da se regresija potpornih vektora (SVR) pokazala nešto boljom, preciznijom, stabilnijom i bržom od regresije potpornih vektora najmanjih kvadrata (LS-SVR) i umjetnih neuronskih mreža (ANN). Za procjenu kinetike trostrukog adsorpcijskog sustava višekomponentnog sustava preporučuje se model SVR. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna. The aim of this work was to develop three artificial intelligence-based methods to model the ternary adsorption of heavy metal ions {Pb2+, Hg2+, Cd2+, Cu2+, Zn2+, Ni2+, Cr4+} on different adsorbates {activated carbon, chitosan, Danish peat, Heilongjiang peat, carbon sunflower head, and carbon sunflower stem). Results show that support vector regression (SVR) performed slightly better, more accurate, stable, and more rapid than least-square support vector regression (LS-SVR) and artificial neural networks (ANN). The SVR model is highly recommended for estimating the ternary adsorption kinetics of a multicomponent system. This work is licensed under a Creative Commons Attribution 4.0 International License.

Gjilan (42˚28’08” V, 21˚27’48” L) is one of the seven largest cities in Kosovo. Throughout the city flow three rivers: Mirusha and Stanishor which mix and discharge into the largest river called Morava. The reason for the research of these rivers is the extreme pollution resulting from the discharge of industrial waters. Analysis of these rivers shows that they are extremely polluted and some physicochemical parameters are not in accordance with the regulations of the European Union (EU) and the World Health Organization (WHO). Parameters analysed are: pH, CW, NTU, DO, COD, BOD5, A-HCl, HCO3, GH, CS, Cl–, Cl2, Ca2+, Mg2+, NO2–, NO3–, PO43–, and NH3–. This work is licensed under a Creative Commons Attribution 4.0 International License. Grad Gjilan (42˚28’08”, V 21˚27’48” L) jedan je od sedam najvećih gradova na Kosovu. Kroz njega prolaze tri rijeke: Mirusha i Stanishor koje se miješaju i ulijevaju u najveću rijeku Moravu. Razlog za istraživanje tih rijeka je njihovo onečišćenje nastalo ispuštanjem industrijskih voda. Analiza tih rijeka pokazuje izrazito onečišćenje te neusklađenost nekih fizikalno-kemijskih parametara s propisima Europske unije (EU) i Svjetske zdravstvene organizacije (SZO). Analizirani su sljedeći parametri: pH, CW, NTU, DO, COD, BOD5, A-HCl, HCO3, GH, CS, Cl–, Cl2, Ca2+, Mg2+, NO2–, NO3–, PO43– i NH3–. Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna.

In recent years, the detection and determination of numerous drugs and pharmaceuticals in various media have become crucial aspects of modern healthcare and environmental management. Among the available sensing techniques, electrochemical methods, particularly those utilising screen-printed electrodes (SPEs) and different portable equipment have emerged as rapid, effective, sensitive, and inexpensive. This study focuses on the detection of the anti-inflammatory drug diclofenac in neutral media. Cyclic voltammetry measurements were conducted to identify diclofenac and determine the kinetics and electrochemical mechanism of its oxidation, along with assessing the surface characteristics of the employed SPEs. Graphene and modified graphene SPEs were explored as nanosensors for this purpose. The surface of the graphene SPE was modified using polyvinylidene fluoride, applied through a drop modification procedure. The morphology of the examined SPEs was observed by means of scanning electron microscope, while the electrolyte (0.1 g of diclofenac per litre of phosphate-buffered solution, pH = 7.4) was analysed using UV-Vis spectroscopy. The results indicate that the studied SPEs exhibit promising potential for the detection of diclofenac. Identifikacija i kvantifikacija brojnih lijekova i drugih farmaceutskih proizvoda u različitim medijima postali su ključni aspekti u suvremenoj zdravstvenoj zaštiti i upravljanju okolišem. Elektrokemijske metode, osobito one koje koriste sitotiskane elektrode i različitu prijenosnu opremu, pokazale su se kao brzim, učinkovitim, osjetljivim i ekonomičnim analitičkim pristupom. Fokus ovog istraživanja bio je na detekciji protuupalnog lijeka diklofenaka u neutralnom mediju. S ciljem identifikacije diklofenaka te određivanja kinetike i elektrokemijskog mehanizma njegove oksidacije, primijenjena je metoda cikličke voltametrije. Procijenjene su i površinske karakteristike primijenjenih sitotiskanih elektroda. U tu svrhu ispitana je primjenjivost grafenskih i modificiranih grafenskih sitotiskanih elektroda kao nanosenzora. Površina grafenskih sitotiskanih elektroda modificirana je kapljičnim postupkom primjenom poliviniliden fluorida. Morfologija sitotiskanih elektroda analizirana je skenirajućom elektronskom mikroskopijom, a elektrolit (0,1 g diklofenaka u litri fosfatnog pufera, pH = 7,4) UV-Vis spektroskopijom. Dobiveni rezultati ukazuju na potencijal proučavanih elektroda za detekciju diklofenaka.

Biological activity of different adamantane derivatives and their application has been described in various reviews. Similarly, many reviews deal with biological activity and application of guanidine compounds. However, up to now no review has been made concerning the guanidine derivatives of adamantane and other polycycles, compounds which incorporate both of these moieties in the same molecule. Therefore, a literature survey of polycyclic guanidine derivatives is here provided and their application as potential pharmacophores stressed. Biološka aktivnost različitih adamantanskih derivata i njihova primjena opisane su u brojnim preglednim člancima. Isto tako, mnogi revijalni članci opisuju biološku aktivnost i primjenu gvanidinskih spojeva. Međutim do sada nije načinjen pregled koji bi se bavio gvanidinskim derivatima adamantana i drugih policikla, tj. spojevima koji sadrže obje navedene podjedinice u istoj molekuli. U ovom radu bit će stoga dan pregled policikličkih derivata gvanidina, i to s naglaskom na njihovu primjenu kao potencijalnih farmakofora.

The region of Médéa (Algeria) located in an agricultural site requires a large amount of drinking water. For this purpose, the water analyses in question are imperative. To examine the evolution of the drinking water quality in this region, firstly, an experimental protocol was done in order to obtain a dataset by taking into account several physicochemical parameters. Secondly, the obtained data set was divided into two parts to form the artificial neural network, where 70 % of the data set was used for training, and the remaining 30 % was also divided into two equal parts: one for testing and the other for validation of the model. The intelligent model obtained was evaluated as a function of the correlation coefficient nearest to 1 and lowest mean square error (RMSE). A set of 84 data points were used in this study. Eighteen parameters in the input layer, five neurons in the hidden layer, and one parameter in the output layer were used for the ANN modelling. Levenberg Marquardt learning (LM) algorithm, logarithmic sigmoid, and linear transfer function were used, respectively, for the hidden and the output layers. The results obtained during the present study showed a correlation coefficient of <i>R</i> = 0.99276 with root mean square error RMSE = 11.52613 mg dm<sup>–3</sup>. These results show that obtained ANN model gave far better and more significant results. It is obviously more accurate since its relative error is small with a correlation coefficient close to unity. Finally, it can be concluded that obtained model can effectively predict the rate of soluble bicarbonate in drinking water in the Médéa region.

Energy costs are the key characteristic of any industrial plant, so that adequate importance should be given to the heat balances calculations at its design stage. The precondition for corresponding calculations is the knowledge of heat properties of reaction system components. To that end, this paper presents data on the heat capacities of vegetable oils and biodiesel. Particular importance has been given to the biodiesel components data, which are fully presented here for the first time. The heat of transesterification reaction calculation is presented here for the first time as well. The heat balances of separate production process phases are delineated. The advances in production technologies and process unit development are also described.