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'Malvazija istarska' (Vitis vinifera L.) jedna je od najznačajnijih bijelih sorata u Hrvatskoj. Njezina kvaliteta prepoznata je kako u Hrvatskoj, tako i šire, stoga se domaći proizvođači sve češće odlučuju za ovu sortu. Razvojem tehnologije i sve većom potražnjom tržišta za pjenušavim vinima, raste i interes lokalnih proizvođača za proizvodnjom pjenušca od 'Malvazije istarske'. Mošt za proizvodnju baznoga vina za pjenušce po svom sastavu treba zadovoljavati svojstva kao što su niža pH vrijednost i koncentracija šećera, te viša ukupna kiselost s većim udjelom vinske kiseline, naspram jabučne. S obzirom na to da se 'Malvazija istarska' uzgaja pretežito u Istri, gdje je klima mediteranska, a najzastupljenije tlo crvenica, teško je zadovoljiti sva navedena svojstva potrebna za proizvodnju baznoga vina, posebice u suhim i vrućim godinama. Poznato je da sastav i dostupnost minerala iz tla ima značajan utjecaj na kemijski sastav mošta. Posebno je to važno za dostupnost kalija, za koji je dokazano da utječe na porast pH vrijednosti mošta i smanjuje koncentraciju ukupne kiselosti što ima nepovoljan utjecaj na kakvoću baznog vina. Također višak kalija često blokira usvajanje magnezija, te dolazi do njihovog nepovoljnog međuodnosa. Kako nedostatak vode tijekom vegetacije može usporiti i smanjiti dostupnost minerala, posebice magnezija bitnog za proces fotosinteze, a time i utjecati na kvalitetu baznoga vina, folijarna gnojidba jedan je od načina da se taj nedostata nadoknadi. Unatoč ovim važnim saznanjima mali broj autora se bavio istraživanjima utjecaja folijarne gnojidbe na sastav i kvalitetu baznoga vina u proizvodnji pjenušca. Stoga je cilj ovog istraživanja bio utvrditi utjecaj folijarne gnojidbe na količinu biogenih elemenata i suhu tvar u lišću vinove loze, te na svojstva mošta (ukupnu kiselost, organske kiseline, pH vrijednost, koncentraciju šećera) i baznoga vina (alkohol, ukupni suhi ekstrakt, pepeo, pH vrijednost, ukupnu kiselost, hlapljivu kiselost). Istraživanje je uključivalo četiri gnojidbena tretmana (T1, T2, T3 i T4) u tri repeticije. Pokus je bio postavljen po slučajnom bloknom rasporedu (RCBD) na sorti 'Malvazija istarska', podloga SO4, kroz dvije godine (2013. i 2014.). Tretmani su bili: T1 - NPK, T2 - NPK + Agromag (6 % MgO), T3 - NPK + Agromag + Fosforo (30 % P205) i T4 - NPK + Agromag + Fosforo + Bio Prot). Dobiveni rezultati ukazuju na postojanje značajnog utjecaja gnojidbenih tretmana na količinu kalija, kalcija, magnezija, željeza, cinka i bakra u lišću 2013., te kalija 2014. godine. Najveći utjecaj na smanjenje kalija u obje godine istraživanja imao je tretman T2 odnosno tretman magnezijem. Pozitivan utjecaj folijarnih tretmana na koncentraciju šećera, pH vrijednost i ukupnu kiselost mošta zabilježen je u 2013. godini, te na pH vrijednost i koncentraciju šećere u 2014. godini. Viši udio vinske kiseline i najniži udio jabučne kiseline imali su tretmani T3 i T4 u obje godine. Istraživanjem je utvrđena pozitivna korelacija između suhe tvari s pH vrijednosti i prinosom, te kalija i kalcija s ukupnom kiselosti u sušnoj 2013. godini. U vlažnoj 2014. godini utvrđena je pozitivna korelacija ukupne kiselosti i kalija, te negativna ukupne kiselosti i magnezija, što dodatno upućuje da je međuodnos kalija i magnezija za vinovu lozu bitniji od njihovih apsolutnih količina. Iako nije utvrđen značajan utjecaj tretmana na kemijski sastav baznoga vina, iz dobivenih rezultata vidljiv je trend opadanja pH vrijednosti i rasta ukupne kiselosti 2013. godine, te trend rasta ukupnog suhog ekstrakta u obje godine. Iz dobivenih rezultata vidljivo je da postoji povoljan utjecaj gnojidbenih tretmana na svojstva mošta i baznoga vina, a kako su se u istraživanju koristile minimalne doze preporučene od proizvođača za pojedina folijarna gnojiva, ostaje mogućnost daljnjih istraživanja. Dobiveni rezultati mogli bi biti znanstveni temelj pri dizajniranju folijarnih gnojidbenih tretmana u vinogradima sličnih agroekoloških karakteristika, gdje se grožđe ciljano koristi za proizvodnju pjenušavog vina. 'Istrian Malvasia' (Vitis vinifera L.) is one of the most important white cultivars in Croatia. Its quality is recognized both in Croatia and throughout the world, which is the reason why domestic producers are increasingly opting for this cultivar. With the development of technology and an increase in the market demand for sparkling wines, there is also a growing interest of local producers in the production of sparkling wines from 'Istrian Malvasia'. In 2018., sparkling wine production accounts for an average of 7 % of global wine production and the volume of global exports accounted for 9 % of the total wine exported worldwide, representing 20 % of the total value of exported wine. That indicate sparkling wines are was increasingly produced in warmer and drier regions of the world, so it is difficult to achieve satisfactory parameters in the chemical composition of the base wine, which limits their production despite the adaptation of agricultural techniques and earlier harvest dates. The composition of must for the production of base wine for sparkling wine should satisfy components such as a lower pH value and sugar concentration, as well a higher content of total acidity with a higher proportion of tartaric acid, compared to malic acid. A high pH in the must is not desirable because it directly affects the wine by reducing the quality and stability of the color, negatively affecting the freshness and aging potential, and giving the wines an inharmonious taste. These negative effects are undesirable in the pro-duction of base wines for sparkling wine, because sparkling wines need freshness and a long aging potential. Preferably, base wines have a pH between 2,90 and 3,10. In base wine, a total acidity of 6,00 – 8,00 g/L is desirable, and this level is reduced by the precipitation of potassium bitartrates during must vinification. Since a high alcohol content in base wines is not desirable and an addi-tional 1,3 – 1,5 % vol. alcohol is formed during secondary fermentation, it is important that the sugar content in the must is not too high. The preferred alcohol content in the base wine is up to 11,5 %. vol. Given that 'Istrian Malvasia' is grown mainly in Istria, where the climate is Mediterranean, and the most common soil is red, it is difficult to satisfy all the mentioned components required for the production of base wine, especially during dry and hot years. It is known that the composition and availability of minerals from the soil have a significant influence on the chemical composition of the must. This is especially important for the availability of potassium, which has been proven to increase the pH value of the must and reduce the concentration of total acidity, which are unfavorable components for base wine. The idea of the possible positive effect of foliar fertilization with magnesium, phosphorus and amino acid-based biostimulants on the potassium decrease of leaves and, consequently, on the chemical composition of must arose from the knowledge of the strong antagonistic effect of potassium and magnesium. Potassium blocks the uptake and especially the translocation of magnesium in the plant much more than vice versa. Therefore, in soils with excess potassium or excessive application of potassium fertilizers, magnesium deficiency often occurs due to their antagonistic relationship and large K/Mg ratio. Foliar application of magnesium decreases the K/Mg ratio. Since the lack of water during growing season can slow down and reduce the availability of minerals, especially magnesium, which is essential for the photosynthesis process, and thus affect the quality of the base wine, foliar fertilization is one of the possibilities which can compensate for this lack. Also, foliar application of magnesium decreases the K/Mg ratio. Despite this important knowledge, a small number of authors have done research on the influence of foliar fertilization on the composition and quality of the base wine in the production of sparkling wines. Therefore, the aim of this research was to determine the influence of foliar treatments on the amount of plant nutrients and dry matter in the leaves, as well as on the properties of the must (total acidity, organic acids, pH value, sugar concentration) and base wine (alcohol, total dry extract, ash, pH value, total acidity, volatile acidity). The research included four fertilization treatments (T1, T2, T3 and T4) in three repetitions. The experiment was set up according to a randomized block arrangement (RCBD) on the cultivar 'Istrian Malvasia', rootstock SO4, for the duration of two years (2013 and 2014). The treatments were as follows: T1 - NPK, T2 - NPK + Agromag (6 % MgO), T3 - NPK + Agromag + Fosforo (30 % P205) and T4 - NPK + Agromag + Fosforo + Bio Prot). The obtained results indicate that there is a significant influence of fertilization treatments on the amount of potassium, calcium, magnesium, iron, zinc and copper in the leaves in 2013, and potassium in 2014. Treatment T2, treatment with magnesium, had the greatest influence on the decrease of potassium in both years. A positive influence of foliar treatments on the sugar concentration, pH value and total acidity of must was recorded in 2013, and on pH value and sugars concentration in 2014. Treatments T3 and T4 had a highest proportion of tartaric acid and the lowest proportion of malic acid in both years. A positive correlation between dry matter with pH value and yield was established by this research, and potassium and calcium with total acidity in the dry year of 2013. In the wet year of 2014, a positive correlation of total acidity and potassium, and a negative correlation of total acidity and magnesium was determined, which additionally indicates that the relationship between potassium and magnesium is more important for grapevine than their absolute amounts. Although no significant influence of the treatment on the chemical composition of the base wine was determined, the obtained results show a trend of a decrease in pH values and an increase of total acidity in 2013, as well as a trend of growth of total dry extract in both years. From the obtained results, it is evident that there is a certain favorable influence of fertilization treatments on the components of the must and the base wine, and as minimum dosages recommended by the manufacturer for individual foliar fertilizers were used in the research, this leaves room for additional research. This approach to the application of foliar fertiliza-tion aimed at correcting the chemical composition of the must could reduce the need for corrective measures in the must and wine during the production process. The obtained results could be a scientific foundation for designing foliar fertilization treatments in vineyards with similar agroecological characteristics, where grapes are targeted for the production of sparkling wines.

Small pore zeolites comprise 8-membered ring pore opening within their framework. They are commercially exploited in automotive catalysis, and they also excel in the industrial production of olefins from methanol (MTO) [1, 2]. In addition, they are extensively studied in gas adsorption, e.g. for selective uptake of CO2 from CH4 that is of great importance for upgrading of natural gas and biogas, as well as for nitrogen oxides abatement from exhaust gases [3, 4]. Herein is reported the preparation of LEV-type as well as LEV/ERI-type intergrown materials at temperatures ranging from 100-200 °C.

High alumina LTA-type zeolite material, so called zeolite A (Si/Al = 1), is an archetype drying agent (water adsorbent) as well as ion exchanger (e.g. in water softening) [1]. Incorporating more Si in the framework, i.e. increasing Si/Al ratio, renders this kind of materials more (hydro)thermally stable and apt for catalytic application, in particular for vehicle exhaust gases purification [2, 3]. Cu-LTA were found exceptionally active catalysts in NH3-SCR even after hydrothermal aging at 900 °C, the temperature at which the commercial catalyst deforms and loses activity [4]. In the scope of this research challenges of preparing high/all- silica LTA zeolites are going to be addressed. Besides, several examples of their successful preparation will be demonstrated.

Organobromine compounds, also called organobromides, are found in a variety of marine natural products (e.g. aeroplysinin-1, tyrian purple, 14-debromoaraplysillin and 14- debromoprearaplysillin) [1]. They are essential synthetic intermediates in the manufacture of derivatives of many natural products, pharmaceuticals, agrochemicals and other fine chemicals [2]. Organobromides are also very useful building blocks for some fundamental chemical transformations such as Grignard reactions, cross- coupling, nucleophilic substitution, etc [3]. Zeolites, as a class of inorganic microporous crystalline aluminosilicate materials [4], are widely used in numerous large-scale applications as catalysts, ion exchange materials, and adsorbents for organic compoundsn[5]. In addition to these conventional uses, zeolites have also emerged as advanced functional materials applied in the fields of luminescence, electricity, magnetism, medicine and microelectronics, etc [6]. In the present research, various esters of trans- cinnamic acid were chosen for 1, 2- dibromination with 1, 3-dibromo-5, 5- dimethylhydantoin (DBDMH) over zeolites beta, Y and ZSM-5 to study the influence of zeolite pore architecture and the reactant size on the product selectivities and reaction mechanism. The 1, 2-dibromination of a various cinnamates was carried out using a stable, non-toxic, inexpensive bromine source, DBDMH, and a zeolite (beta, Y or ZSM-5) as a catalyst at room temperature. In the present research, methyl trans-cinnamate was chosen to study the molar ratio of DBDMH (1.0 or 1.5 equiv), solvents (aceton, acetonitrile, chloroform, dichloromethane, diethyl ether, diisopropyl ether, dimethyl sulfoxide, ethanol, tetrahydrofuran and toluen), the reaction period (2 h to 24 h) and the quantity of zeolite catalysts (20 and 40 wt%) have been varied. Blank reactions were also carried out in the absence of catalyst. The progress of the reaction was monitored by TLC and by RP-HPLC. Reaction conditions were optimized by use of diethyl ether as solvents with 1.5 molar equivalents of DBDMH and 40 wt% of the catalyst. With the optimal condition in hand, esters were explored as electron-withdrawing groups on the 1, 2- dibromination reaction. The obtained results showed that the cinnamate conversion over 90% was achieved for both zeolite beta and Y in diethyl ether at room temperature. ZSM-5 is not as effective catalyst as the other two. In the absence of a catalyst the reactions were significantly slower. According to the 1H NMR it was found that in all cases the 1, 2-dibromination proceeded with anti- stereoselectivity to give the 1, 2- dibromide compounds.

S obzirom na široku primjenu tekstilija u bolničkom okružju za različite namjene kao što su posteljno rublje, zaštitna odjeća, gaze i zavoji, osim strukturalnih, mehaničkih, fizikalno- kemijskih i antimikrobnih svojstva nužno je zadovoljiti i svojstvo udobnosti pri dodiru s kožom. Na osjet udobnosti imaju utjecaj različite karakteristike tkanine kao što su savojna i tlačna svojstva, toplinska vodljivost te frikcijska svojstva površine. Za detaljnu karakterizaciju morfoloških karakteristika površine tkanog materijala potrebno je profil hrapavosti sagledati na nekoliko razina: razini površine niti (uvojitost pređe, dlakavost), razini niti (gustoća osnove i potke i utkanje) te razini jedinice veza. Na svim tim razinama uočavaju se topografske specifičnosti površine tkanine koje se opisuju parametrima hrapavosti i valovitosti površine te morfologijom profila. Tipična topografija se izražava periodičnim ponavljanjem valova u okomitom i horizontalnom smjeru koji proizlazi iz strukture tkanine. U radu je provedeno ispitivanje udobnosti na razini površine niti pamuk/poliesterske (50:50) tkanine u atlas vezu s ciljem karakterizacije morfologije njene površine prije i nakon provedenih 3 i 10 ciklusa pranja primjenom uređaja za mjerenje opipa tkanine, Fabric Touch Tester (FTT) SDL Atlas, FTT M293. Obzirom da FTT daje samo brojčane vrijednosti ocjene i srednje vrijednosti amplituda i valnih duljina unutar profila hrapavosti, za analizu izmjerenih vrijednosti metoda obrade podataka je dodatno modificirana radi dubljeg uvida u hrapavost tkanine koja se ispituje s ciljem definiranja udobnosti. Iz rezultata filtriranih profila vidljivo je kako se povećavanjem broja pranja na razini površine niti hrapavost smanjuje, dok se na razini jedinica veza hrapavost povećava. Također, dobiveni rezultati ukazuju da promjene morfološkog parametra zaobljenosti profila ovisi o broju ciklusa pranja, a na razini jedinice veza o ponašanju sustava osnove i potke tijekom procesa pranja.

Cilj ovog rada bio je istražiti utjecaj i postojanost obrade pamučnih tkanina otopinom kitozana i ulja čajevca uz prisutnost maleinske kiseline primjenom UV-C zračenja. Kupelj za obradu pripremljena je uz miješanje na magnetskoj miješalici u trajanju od 15 minuta uz 800 o/min. Nakon toga su pamučni uzorci namočeni u kupelj i ocijeđeni na fularu uz efekt cijeđena približno 100 %. Uzorci su stavljeni na odležavanje u autoklav na 80 oC u vremenu od 24 h. Nakon odležavanja uzorci su osušeni konduktivno na temperaturi od 100 oC u vremenu od 4 minute te su kondenzirani primjenom UV zračenja UV komore (Solarscreen Test Chamber STC 01) s UV-C žaruljom snage 11 W, napona 37V i struje 0, 33 A u trajanju od 30 minuta. Uzorci su podvrgnuti postupku pranja prema standardu EN ISO 15797:2017 uz primjenu standardnog deterdženta s optičkim bjelilima bez fosfata (WFK 88060) i ɛ(ftalimido) peroksi heksanske kiseline (PAP). U okviru istraživanja ispitana je antimikrobna aktivnost tkanine u skladu sa standardom AATCC 147. Fizikalno kemijske promjene na obrađenim tkaninama prije i nakon ciklusa pranja ispitane su Fourierovom transformacijskom infracrvenom spektroskopijom u tehnici prigušene ukupne refleksije (FTIR-ATR). Gustoća pamučne tkanine u smjeru osnove i potke prije i nakon provedenog ciklusa pranja određena je pomoću Dino Lite svjetlosnog digitalnog USB mikroskopa. Rezultati ispitivanja antimikrobne učinkovitosti pokazuju da su obrađene tkanine prije i nakon provedenih ciklusa pranja otporne na djelovanje bakterija i gljivica, što ukazuje na pozitivan učinak ulja čajevca te uspješnost provedenog procesa umrežavanja.

Nikada kao do sada nije bila toliko jaka svijest o potrebi za ostvarenjem higijene na svim poljima društvenog života. Ono što je godinama bilo na marginama, pojavom koronavirusa promijenilo je shvaćanje i gledište u svakodnevnom životu čovjeka. Higijena, dezinfekcija i antimikrobnost postali su nezamjenjiv parametar. Štetni utjecaji mikroorganizama povećali su potrebu za razvojem antibakterijskih i antimikrobnih materijala u mnogim područjima primjene. Idealni antimikrobno obrađen tekstil trebao bi biti učinkovit protiv širokog spektra bakterijskih i gljivičnih vrsta, ali istodobno pokazivati i nisku toksičnost prema čovjeku i okolišu. Zbog uštede na svim poljima, pa tako i u njezi, danas se tekstilije nastoji prati na što nižoj temperaturi. Upravo radi toga postoji opasnost nedostatne termičke dezinfekcije tekstilija. Kako bi se ovo spriječilo, tekstil se antimikrobno obrađuje različitim postupcima. Vodeći se načelom racionalizacije i uštede, ranijim istraživanjima je modificiran standardni proces pranja bolničkih tekstilija tako da je snižena temperatura pranja i primijenjeno ekološko sredstvo za kemijsko izbjeljivanje i dezinfekciju. Optimirani proces pranja je pokazao povoljne primarne i sekundarne učinke na višestruko opranim pamučnim materijalima. Kako bi se dobila vrijedna saznanja koja će ili potvrditi njegovu svrsishodnost ili pokazati novi smjer istraživanja, optimirani proces pranja je primijenjen i na antimikrobno obrađene tekstilije. U tu svrhu tekstilije su deset puta prane, a rezultati su pokazali da antimikrobna svojstva u potpunosti ostaju očuvana.

Interzeolite conversion is a zeolite synthesis avenue that uses a crystalline zeolite material as a source of T atoms to obtain another crystalline zeolite [1, 2]. It is a principal method for preparation of certain zeolites such as CHA-type materials [3, 4]. The benefits of this approach with respect to conventional direct synthesis route from chemicals via amorphous precursors are reduced syntheses periods (enhanced crystallization rate), high yields, and the use of alternative organic structure directing agents (OSDAs) [5]. Besides, interzeolite conversion may provide materials of distinct features compared to the ones from classical synthesis mixtures thus expanding the opportunities of designing zeolite materials with target properties [2, 6]. Taking all this into consideration, interzeolite conversion is regarded as synthesis route with high potential in green chemistry era. Recently was reported mechanochemically induced interzeolite conversion [7] that may improve zeolite production in terms of chemicals used, their quantity, yielded waste and energy consumption as well as costs and thus represents an advancement in environment protection. Mechanochemical methods have gained a lot of attention in the past several years, especially as a possible solution for various drawbacks of solution-based syntheses and processes [8]. The present work brings the previous results to potentially even more environment-friendly level – naturally occurring zeolite mineral clinoptilolite (HEU-type) was used as source material in zeolite synthesis. Clinoptilolite was milled with NaOH, KOH, CsOH and tetramethylammonium hydroxide (TMAOH) with a small amount of added water at 110 °C. The reactions were overseen in situ by synchrotron XRD. In the presence of TMAOH any change takes place and the starting material remains intact for 90 minutes. With NaOH and KOH are observed peaks of the clinoptilolite, but they appear and disappear which may be due to experimental issues. The interzeolite conversion occurred promptly in the milled system using CsOH as mineralizer, yielding ANA after 30 minutes suggesting that the interzeolite conversion is quicker in the presence of CsOH than NaOH, KOH and TMAOH. It is expected that the findings reported here will provide guidelines for designing and conducting further ball milling experiments to achieve even more environment-friendly process of zeolite synthesis.

Nanosized Cu-containing ZSM-5 catalysts with different n(Si)/n(Al) ratio of 20.4-54.7 were prepared by ion-exchange. The physico- chemical characterization clearly shows that the molar ratio of framework T atoms influences the nature and distribution of copper species. According to DR UV-Vis, TPR-H2, EPR, or FT-IR spectroscopy analyses, the amount of aggregated copper species increases with increasing the framework n(Si)/n(Al) ratio. Thus, the activity of the Cu-containing ZSM-5 with n(Si)/n(Al) ratio of 50.9- 54.7 in the selective catalytic NO reduction with NH3 (NH3-SCR- DeNOx) significantly decreases compared to the other materials (n(Si)/n(Al) ratio of 20.4-21.2). The reaction mechanism has been discussed in light of the results of 2D COS (two-dimensional correlation spectroscopy) analysis of IR spectra and catalytic properties of the zeolites. The results make evident that enhanced activity of Cucontaining ZSM-5 in NH3-SCR-DeNOx is correlated with the formation of different NOx- under the experimental conditions.

Bromination reactions represent one of the most useful transformations in organic chemistry as the reaction delivers products with new C–Br bonds that can be further functionalized. Traditionally, bromination of arenes is conducted in solution using molecular bromine, a corrosive and toxic reagent. In this presentation a solvent-free mechanochemical alternative to carry out the bromination of arenes in a ball mill will be described. Key for the mechanochemical protocol was the use of zeolites as recyclable catalysts which enabled the halogenation to proceed using various solid brominating agents. Posterior transfer of the ball milling approach into a continuous mechanochemical protocol using a twin- screw extruder was also accomplished. This new approach features green chemistry aspects of mechanochemistry, and complements other mechanochemical bromination methodologies.

Zeoliti su klasa anorganskih spojeva koji se sastoje od atoma aluminija i silicija premoštenih kisikom. U svojoj strukturi sadrže kanale i šupljine koje, ovisno o strukturnom tipu zeolita mogu biti do 2 nm u promjeru, u kojima su obično smješteni kationi alkalijskih i zemnoalkalijskih metala. Ti kationi se mogu zamijeniti drugim kationima [1] ili kompleksnim spojevima. Pokazano je kako se razni policijanometalati, kompleksni anioni opće formule [M(CN)x]y- mogu otopinski sintetizirati unutar šupljina zeolita. [2] U ovom radu mehanokemijski su sintetizirani policijanometalati prijelaznih metala unutar šupljina zeolita Y (strukturnog tipa FAU). Niklov(II) klorid (NiCl2), kobaltov(II) nitrat (Co(NO3)2), manganov(II) klorid (MnCl2) i bakrov(II) nitrat (Cu(NO3)2), zajedno sa kalijevim cijanidom (KCN) i natrijevom formom zeolita Y, korišteni su u mehanokemijskoj sintezi. Mehanokemijska sinteza provedena je na dva načina: postupno i u jednom koraku. U postupnoj sintezi prvo je mljevenjem napravljena ionska izmjena natrijevih kationa sa kationima prijelaznih metala. Dobiveni produkti su zatim mljeveni s KCN u odgovarajućim omjerima. Dobiveni produkti analizirani su infracrvenom spektroskopijom i difrakcijom rentgenskog zračenja na polikristalnom uzorku. Postupnom sintezom dobiveni su tetracijanonikelat(II) ; [Ni(CN)4]2−, heksacijanokobaltat(II) ; [Co(CN)6]4− i heksacijanomanganat(III) ; [Mn(CN)6]3-. U slučaju bakra(II) uspješno je napravljena ionska zamjena, ali policijanometalatni kompleks nije dobiven. Sintezom u jednom koraku priređen je niklov(II) cijanid ; Ni(CN)2. Ovim je istraživanjem pokazano kako je mehanokemija pogodna alternativa za sintezu policijanometalat unutar šupljina zeolita uz očuvanje kristalne strukture istog.

Zeolites are microporous crystalline materials broadly used as ion-exchangers, adsorbents and catalysts, among others. They are comprised of TO4 tetrahedra which assemble into a supramolecular network with well-defined channels and cavities.1 Today there are 253 structural types of zeolites with different properties and applications.2 Zeolites are usually synthesized over a few days or weeks by solvothermal methods.1 This kind of process is very inefficient in terms of time and resources. In an attempt to develop eco-friendlier, cheaper and more rapid methods of zeolite synthesis, we have employed thermally controlled mechanochemistry ; enabling mechanochemical reactions to be conducted at temperatures up to 250 °C.3 We have found that by milling zeolite Y with different bases (sodium, potassium and cesium hydroxide) with and without water at 110 °C yields new products in only a few minutes. Combined with in situ PXRD measurements collected at the Deutsches Elektronen-Synchrotron (DESY), we have identified the intermediate and final products along with the time of their formation. This is to our knowledge the first successful interzeolite conversion carried out by mechanochemical means.

The synthesis of BEA- and MFI-type zeolites was studied in a system that in the all-silica form remains amorphous upon hydrothermal treatment at 150 and 180 °C. In the Al containing systems the initially formed phase is BEA-type zeolite. MFI-type material is formed once the reaction temperature is increased. Moreover, the addition of Na+/K+ to silicate mixture also yields MFI-type materials. The collected data indicate distinct formation mechanisms of these two types of materials.

The collected set of results clearly illustrates the potential of mechanochemical treatment for carrying out interzeolite conversion reactions in a rather short period of time and with significantly reduced water content with respect to conventionally performed reactions of this type. Evidently, this makes the ball milling procedure more ecologically sound than the classic method of interzeolite conversion. Further, the phase composition and the properties of the formed material arise as an outcome of the subtle interplay of kinetic and thermodynamic factors. They ensue as a consequence of numerous events (condensation, (de)polymerization, (de)protonation, etc.) taking place concurrently in the synthesis mixture. It is expected that the findings reported here will provide guidelines for designing and conducting further ball milling experiments to achieve even more environment-friendly process of interzeolite conversion.

In this study, the antimicrobial ability of textile fabrics achieved with dimethyltetradecyl (3-(trimethoxysilyl) ammonium chloride in the presence of 1, 2, 3, 4-butane tetracarboxylic acid was investigated. A conventional dip-pad-dry-cure method was applied for antimicrobial textile finishing. After dipping samples were aged in the bath for 24 h and then padded on a padding machine, dried for 2 min at 110 °C and then thermocondensed at 160 °C for 5 min. Samples were washed according to the standard EN ISO 15797 up to 3 washing cycles. Physicochemical changes on the treated fabrics before and after washing were tested by Fourier infrared spectrometry in ATR technique (FTIR-ATR), and the electrokinetic analyse was performed to determine change in the fabric surface charge on SurPASS. The antimicrobial activity of the fabrics was determined according to the AATCC 147 standard. The pH values of the material surface after one and three washing cycles were also determined.

Zeoliti su mikroporozni kristalni materijali koji se sastoje od TO4 tetraedara koji grade supramolekulske mreže s dobro definiranim kanalima i šupljinama. Danas su poznata 253 različita strukturna tipa zeolita. Našli su široku primjenu kao ionski izmjenjivači, adsorbensi i katalizatori, zbog čega su vrlo značajni materijali u industriji. Klasične metode priprave zeolita obično uključuju korištenje solvotermalnih metoda i uvjeta koje traju nekoliko dana ili čak tjedana i troše puno resursa i vremena.[1] S ciljem da se pronađu jeftinije i brže metode sinteze zeolita, koristili smo termički kontroliranu mehanokemiju – novo razvijenu tehniku koja omogućuje izvođenje mehanokemijskih reakcija pri povišenim temperaturama do 250 °C. [2] U ovom smo radu pokazali kako se mljevenjem zeolita Y s različitim bazama (kalijevim, natrijevim i cezijevim hidroksidom), s i bez vode, pri 110 °C produkt može dobiti u samo nekoliko minuta, dok solvotemalnim metodama takav produkt ne nastaje niti nakon dva dana. Uz pomoć in situ PXRD mjerenja napravljenih na Deutsches Elektronen- Synchrotronu (DESY), identificirali smo intermedijerne faze, finalne produkte te vremena njihovog nastajanja, dajući mogućnost provođenja selektivnih reakcija interzeolitne konverzije zeolita Y kako bi se priredili drugi zeoliti.

This paper deals with the synthesis conditions–defect formation relationship in zeolites. Silicalite-1 (MFI-type) is used as a model material. Samples synthesized from a system with high basicity (at 100 °C), a system with moderate basicity (at 150 °C), and a fluoride- containing system in neutral medium (at 170 °C) were compared. Well-crystallized materials with sizes ca. 0.1, 1-10, and 30-40 µm were obtained. The samples are analyzed by complementary methods providing information on the short- and long-range order in the zeolite framework. A strong correlation between the number of point defects in the zeolite framework and preparation conditions is established. Silicalite-1 synthesized under mild synthesis conditions from a highly basic system exhibits a larger number of framework defects and thus low hydrophobicity. Further, the calcined samples were subjected to aluminum and silicon incorporation by post- synthesis treatment. The Al/Si incorporation in the zeolite framework and its impact on the physicochemical properties is studied by XRD, TEM/SEM, solid-state NMR, FTIR, and thermogravimetric analyses. The defects healing as a function of the number of point defects in the initial material and zeolite crystal size is evaluated. The results of this study will serve for fine-tuning zeolite properties by in situ and post-synthesis methods.

International audience; Fischer-Tropsch synthesis (FTS) is an essential approach to convert coal, biomass, and shale gas into fuels and chemicals, such as lower olefins, gasoline, diesel, and so on. In recent years, there has been increasing motivation to deploy FTS at commercial scales which has been boosting the discovery of high performance catalysts. In particular, the importance of support in modulating the activity of metals has been recognized and carbonaceous materials have attracted attention as supports for FTS. In this review, we summarised the substantial progress in the preparation of carbon-based catalysts for FTS by applying activated carbon (AC), carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon spheres (CSs), and metal-organic frameworks (MOFs) derived carbonaceous materials as supports. A general assessment of carbon-based catalysts for FTS, concerning the support and metal properties, activity and products selectivity, and their interactions is systematically discussed. Finally, current challenges and future trends in the development of carbon-based catalysts for commercial utilization in FTS are proposed.

CHA-type zeolites are commercially employed materials in the exhaust gas treatment for the selective catalytic reduction of nitrogen oxides and as the main catalyst in the methanol to olefin conversion technology. In line with general trends of modern society, there is a demand to develop more environment-friendly synthesis routes and improve their performance in the mentioned applications as well as in the other potential fields of usage. For this reason, numerous studies with the aim to meet these requirements are conducted. Acidic properties and particularly the distribution of Al species represent some of the crucial features that determine the efficiency of zeolite materials. Herein is investigated the correlation between the synthesis conditions of a series of SSZ-13 zeolite materials and their respective properties are evaluated by a range of characterization techniques.

Zeolites are used in many fields of human activities [1]. Besides, new potential applications constantly emerge so understanding their possible impact on the environment is necessary [2]. In the frame of this study, zeolite beta nanoparticles were synthesized and characterized by a complimentary set of experimental techniques. Their potential negative impact towards environment was evaluated using zebrafish Danio rerio embryos embryotoxicity test [3]. Such a comprehensive study pinpointed zeolite nanoparticles as safe materials and opened the door for their application, but also emphasized the need to reduce the presence of organic structure directing agents in nanosized zeolite synthesis reaction mixtures.

Malvazija istarska (Vitis vinifera L.) smatra se autohtonom istarskom sortom i jedna je od najznačajnijih bijelih sorata u Hrvatskoj. Potražnja za vinima ove sorte sve više raste, jer su njezinu kvalitetu prepoznali mnogi potrošači kako Hrvatske, tako i cijeloga svijeta. Domaći porizvođači u Istri sve češće biraju ovu sortu i kao bazu za proizvodnju pjenušavih vina, koja su izuzetno popularna tokom turističke sezone. No, kako Istru karakterizira mediteranska klima, a najzastupljenije tlo je crvenica, vina od Malvazije istarske najčešće imaju povišenu pH vrijednost. Jedan od razloga je i previsoka količina kalija u tlu koji negativno utječe na pH vrijednost mošta. Kako je pH vrijednost važan parametar u proizvodnji baznog vina i poželjno je da bude što niži, pretpostavlja se da bi ga se moglo smanjiti folijarnom primjenom Mg zbog međusobnog antagonističkog odnosa ta dva iona. Ukupna kiselost i pH međusobno su povezani, a direktno utječu na svježinu i potencijal starenja baznoga vina i pjenušaca. Stoga je cilj ovog istraživanja bio utvrditi utječe li folijarni tretman s Mg na pH vrijednost u moštu. Dvogodišnji pokus postavljen je 2013. i 2014. godine, s četiri gnojidbena tretmana u tri ponavljanja (NPK, NPK + Agromag (6% MgO), NPK + Agromag + Fosforo(30% P205) i NPK + Agromag + Fosforo + Bio Prot). Značajni utjecaj postignut je sa tretmanima NPK + Agromag + Fosforo i NPK + Agromag + Fosforo + Bio Prot. Sveukupno određena pH vrijednost u moštu bila je od 3, 00 do 3, 23.

Zeolites are one of the most widely used solid heterogeneous catalysts due to their unique properties. Herein, a series of nanosized ZSM-5 samples (MFI framework type-material) was synthesized at 170, 150, 120, and 100 °C. Experimental data show that the decrease of crystallization temperature leads to significant changes in zeolite properties. Crystals synthesized at 100 °C exhibit many framework defects with lower acid-site density, strength, and a larger external surface area. The prepared materials have been tested as catalysts in DME synthesis and MTO reaction.