Calcium oxalate and gallic acid: structural characterization and process optimization toward obtaining high contents of calcium oxalate monohydrate and dihydrate

The search for an efficient drug or inhibitor in the formation process of kidney stones has been a promising research topic towards reducing the risks of the formation of disease. However, several challenges have been faced in investigating the most common constituents of kidney stones, calcium oxalate and its hydrate forms (COM, COD and COT). This study focuses on the preparation and structural characterization (TG, XRD, FTIR, SEM) of calcium oxalate hydrates in the presence of gallic acid (GA) and by varying operating parameters such as temperature (25 °C, 36.5 °C and 48 °C), pH (5.6, 6.5 and 7.5) and amount of added GA (ranging from 100 mg to 1000 mg). Response surface methodology was applied in order to evaluate the effects of operating parameters in the formation of COM and COD, and for the process optimization towards maximizing their content in samples. The results indicated that GA inhibited the formation of COM (0–100%) and promoted the formation of COD (0 ≤ 99%), while a medium pH and the amount of added GA showed a significant effect in the process of COD formation. In order to investigate the interactions established in the formation process and the possible adsorption between GA and the formed crystals, electrochemical measurements were performed

Synthesis of lithium-nickel-based complex oxides for energy storage

Složeni metalni oksidi jedni su od najistraživanijih vrsta spojeva zbog svojih raznolikih svojstava i primjene, posebno u današnje vrijeme kada postoje sve veći zahtjevi za inovativnim materijalima sa širokim spektrom svojstava. Ovim radom istraživane su optimalne količine litijevih iona dopiranih u sustav niklova oksida, s ciljem nastanka različitih kristalnih struktura Li-Ni-O sustava. Svi spojevi sintetizirani su modificiranom citratnom sol-gel sintezom uz provođenje kalcinacije u struji zraka, pri temperaturama od 600°C i 700°C. Nastali produkti detaljno su okarakterizirani pomoću nekoliko analitičkih metoda: rentgenske difrakcije na prahu (PXRD), termogravimetrijske analize s razlikovnom pretražnom kalorimetrijom (TGA/DSC) te analize specifične površine Brunauer–Emmett–Teller metodom (BET) i poroznosti teorijom funkcionala gustoće (DFT).Complex metal oxides are one of the most investigated types of compounds due to their diverse properties and applications, especially nowadays when there are increasing demands for innovative materials with a wide range of properties. This work presents the fundamental research of the optimal amounts of lithium ions doped into the nickel oxide system, with the aim of producing different single-phase Li-Ni-O systems. All compounds were synthesized by a modified citrate sol-gel synthesis with calcination in a stream of air, at temperatures of 600°C and 700°C. The products were characterized in detail using several analytical methods such as: powder X-ray diffraction (PXRD), thermogravimetric analysis with differential scanning calorimetry (TGA/DSC), specific surface area analysis using the Brunauer–Emmett–Teller method (BET) and porosity analysis using the density functional theory method (DFT)

Influence of gallic acid on calcium oxalate precipitation

Potraga za učinkovitim lijekom ili inhibitorom u procesu stvaranja bubrežnih kamenaca ima bila obećavajuća tema za istraživanje smanjenja rizika od nastanka bolesti. Međutim, suočeno je s nekoliko izazova u istraživanju najčešćih sastojaka bubrežnih kamenaca, kalcijev oksalat i njegovi hidratni oblici (COM, COD i COT). Ova studija usmjerena je na pripremu i strukturna karakterizacija (TG, XRD, FTIR, SEM) hidrata kalcijevog oksalata u prisutnosti galne kiseline (GA) i mijenjanjem radnih parametara kao što su temperatura (25 C, 36,5 C i 48 C), pH (5,6, 6,5 i 7,5) i količinu dodanog GA (u rasponu od 100 mg do 1000 mg). Odgovor površinska metodologija primijenjena je kako bi se ocijenili učinci radnih parametara u formiranje COM i COD, te za optimizaciju procesa prema maksimiziranju njihovog sadržaja uzorci. Rezultati su pokazali da GA inhibira stvaranje COM (0-100%) i pospješuje formiranje KPK (0 99%), dok su srednji pH i količina dodanog GA pokazale značajan učinak u procesu nastanka KPK. Kako bi se istražile interakcije uspostavljene u proces stvaranja i moguća adsorpcija između GA i formiranih kristala, elektrokemijski izvršena su mjerenja.The search for an efficient drug or inhibitor in the formation process of kidney stones has been a promising research topic towards reducing the risks of the formation of disease. However, several challenges have been faced in investigating the most common constituents of kidney stones, calcium oxalate and its hydrate forms (COM, COD and COT). This study focuses on the preparation and structural characterization (TG, XRD, FTIR, SEM) of calcium oxalate hydrates in the presence of gallic acid (GA) and by varying operating parameters such as temperature (25 C, 36.5 C and 48 C), pH (5.6, 6.5 and 7.5) and amount of added GA (ranging from 100 mg to 1000 mg). Response surface methodology was applied in order to evaluate the effects of operating parameters in the formation of COM and COD, and for the process optimization towards maximizing their content in samples. The results indicated that GA inhibited the formation of COM (0–100%) and promoted the formation of COD (0 99%), while a medium pH and the amount of added GA showed a significant effect in the process of COD formation. In order to investigate the interactions established in the formation process and the possible adsorption between GA and the formed crystals, electrochemical measurements were performed

Influence of gallic acid on calcium oxalate precipitation

Potraga za učinkovitim lijekom ili inhibitorom u procesu stvaranja bubrežnih kamenaca ima bila obećavajuća tema za istraživanje smanjenja rizika od nastanka bolesti. Međutim, suočeno je s nekoliko izazova u istraživanju najčešćih sastojaka bubrežnih kamenaca, kalcijev oksalat i njegovi hidratni oblici (COM, COD i COT). Ova studija usmjerena je na pripremu i strukturna karakterizacija (TG, XRD, FTIR, SEM) hidrata kalcijevog oksalata u prisutnosti galne kiseline (GA) i mijenjanjem radnih parametara kao što su temperatura (25 C, 36,5 C i 48 C), pH (5,6, 6,5 i 7,5) i količinu dodanog GA (u rasponu od 100 mg do 1000 mg). Odgovor površinska metodologija primijenjena je kako bi se ocijenili učinci radnih parametara u formiranje COM i COD, te za optimizaciju procesa prema maksimiziranju njihovog sadržaja uzorci. Rezultati su pokazali da GA inhibira stvaranje COM (0-100%) i pospješuje formiranje KPK (0 99%), dok su srednji pH i količina dodanog GA pokazale značajan učinak u procesu nastanka KPK. Kako bi se istražile interakcije uspostavljene u proces stvaranja i moguća adsorpcija između GA i formiranih kristala, elektrokemijski izvršena su mjerenja.The search for an efficient drug or inhibitor in the formation process of kidney stones has been a promising research topic towards reducing the risks of the formation of disease. However, several challenges have been faced in investigating the most common constituents of kidney stones, calcium oxalate and its hydrate forms (COM, COD and COT). This study focuses on the preparation and structural characterization (TG, XRD, FTIR, SEM) of calcium oxalate hydrates in the presence of gallic acid (GA) and by varying operating parameters such as temperature (25 C, 36.5 C and 48 C), pH (5.6, 6.5 and 7.5) and amount of added GA (ranging from 100 mg to 1000 mg). Response surface methodology was applied in order to evaluate the effects of operating parameters in the formation of COM and COD, and for the process optimization towards maximizing their content in samples. The results indicated that GA inhibited the formation of COM (0–100%) and promoted the formation of COD (0 99%), while a medium pH and the amount of added GA showed a significant effect in the process of COD formation. In order to investigate the interactions established in the formation process and the possible adsorption between GA and the formed crystals, electrochemical measurements were performed

Synthesis of lithium-nickel-based complex oxides for energy storage

Složeni metalni oksidi jedni su od najistraživanijih vrsta spojeva zbog svojih raznolikih svojstava i primjene, posebno u današnje vrijeme kada postoje sve veći zahtjevi za inovativnim materijalima sa širokim spektrom svojstava. Ovim radom istraživane su optimalne količine litijevih iona dopiranih u sustav niklova oksida, s ciljem nastanka različitih kristalnih struktura Li-Ni-O sustava. Svi spojevi sintetizirani su modificiranom citratnom sol-gel sintezom uz provođenje kalcinacije u struji zraka, pri temperaturama od 600°C i 700°C. Nastali produkti detaljno su okarakterizirani pomoću nekoliko analitičkih metoda: rentgenske difrakcije na prahu (PXRD), termogravimetrijske analize s razlikovnom pretražnom kalorimetrijom (TGA/DSC) te analize specifične površine Brunauer–Emmett–Teller metodom (BET) i poroznosti teorijom funkcionala gustoće (DFT).Complex metal oxides are one of the most investigated types of compounds due to their diverse properties and applications, especially nowadays when there are increasing demands for innovative materials with a wide range of properties. This work presents the fundamental research of the optimal amounts of lithium ions doped into the nickel oxide system, with the aim of producing different single-phase Li-Ni-O systems. All compounds were synthesized by a modified citrate sol-gel synthesis with calcination in a stream of air, at temperatures of 600°C and 700°C. The products were characterized in detail using several analytical methods such as: powder X-ray diffraction (PXRD), thermogravimetric analysis with differential scanning calorimetry (TGA/DSC), specific surface area analysis using the Brunauer–Emmett–Teller method (BET) and porosity analysis using the density functional theory method (DFT)