Synthesis of PEDOT/ZnO Photocatalyst: Validation of Photocatalytic Activity by Degradation of Azo RR45 Dye Under Solar and UV-A Irradiation

To study the photocatalytic efficiency of wastewater treatment processes, the nanocomposites of conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and ZnO nanoparticles were prepared by in-situ synthesis. ZnO is an excellent photocatalyst under UV light, but due to high band gap, photons of visible light have insufficient energy to excite electrons from valence to conductive band, which limits its activity under visible light and therefore practical usage is limited. The PEDOT conductive polymer was used to increase the photocatalytic activity of ZnO since conductive polymers are known as efficient electron donor and good electron transporters upon visible-light excitation. Polymerization of pure PEDOT and PEDOT/ZnO nanocomposites was carried out at varying monomer:oxidant ratio (1:2; 1:3; 1:5) with the ammonium persulfate (APS) used as the oxidant. Samples were characterized by FTIR spectroscopy, XRD analysis, SEM microscopy, UV-Vis spectroscopy and TG analysis. Photocatalytic activity was assessed through removal of C.I. Reactive Red 45 (RR45) azo dye under simulated Solar and UV-A irradiation. Photocatalysis was monitored by measuring discoloration of RR45 using UV/Vis spectroscopy. The results indicate that very low concentration of PEDOT conductive polymer in PEDOT/ZnO nanocomposite can significantly contribute to the efficiency of the photocatalytic process during wastewater treatment. This work is licensed under a Creative Commons Attribution 4.0 International License

THE IMPORTANCE OF ANESTHESIA IN DIAGNOSTIC TESTS OF ENDOBRONCHIAL ULTRASOUND

Prikazan je mogući anestezijski postupak za dijagnostički endobronhijski ultrazvuk. (EBUS). EBUS je specifi čna pretraga za dijagnostiku novonastale hilarne i/ili medijastinalne limfadenopatije te tumora pluća. Anestezija olakšava izvođenje ovog dijagnostičkog postupka bolesniku i liječniku. Iz dosadašnjih studija vidljivo je da su u primjeni različite tehnike anestezije. Postupak se može izvesti u sedaciji primjenom lokalnog anestetika i općoj anesteziji. Kod primjene sedacije lokalnim anestetikom bolesnik diše spontano, a u općoj anesteziji se dišni put održava laringealnom maskom ili orotrahealnim tubusom. Bolesniku u dobi od 57 godina, tjelesne težine (TM) 94 kg, ASA I (The American Society of Anesthesiologists), uredne plućne funkcije, bez poznatih alergija, indicirana je dijagnostička pretraga EBUS zbog povećanih limfnih čvorova u medijastinumu. Dijagnostička pretraga EBUS izvodi se na udaljenom radilištu koji je opremljen anesteziološkim uređajem Datex-Ohmeda S5 Aespire 1990. godine i monitorom Philips IntelliVue MP60. te smo anestezijski postupak prilagodili postojećim uvjetima. Monitorira se srčana frekvencija, elektrokardiogram (EKG), broj respiracija, krvni tlak, te postotak zasićenja hemoglobina kisikom pulsnim oksimetrom. Postavljena je intravenska kanila čija se prohodnost održava infuzijom 500 mL 0,9 % NaCl. Nakon lokalne anestezije 1-2 mL 1 %-tnim lidokainom orofaringealnog područja bolesnik je sediran midazolamom (2,5 mg), n-fentanilom (5 mcg) te propofolom (bolus 100 mg i doza održavanja kontinuirano 4 mg /min). Nakon fl eksibilne bronhoskopije kroz nos od 5 minuta nastavlja se EBUS kroz usnik u trajanju od 22 minute. Dijagnostički postupak ukupno je trajao 27 minuta. Za vrijeme anestezije bolesnik je bio respiracijski i hemodinamski stabilan, diše spontano uz suplementaciju smjese zrak/kisik 1 : 1 volumnim modalitetom maksimalnog volumena 700 mL i frekvencije maksimalno 33/min. S takvom modifi - kacijom se postigla zadovoljavajuća ventilacija i zasićenost kisikom koja je na periferiji iznosila 94±4 %. Sistolički krvni tlak je iznosio 157±7 mm Hg, a dijastolički 78±9 mm Hg. Srčana frekvencija bila je 88±8/min. Bolesnik se nakon učinjenog dijagnostičkog zahvata uredno probudio. Anestezija je protekla bez komplikacija.A possible anesthetic procedure for diagnostic endobronchial ultrasound (EBUS) is presented. EBUS is a specifi c search for the diagnosis of newly emerged hilar and/or mediastinal lymphadenopathy and lung tumors. Anesthesia facilitates the performance of this diagnostic procedure for the patient and the physician. From previous studies, it is apparent that various anesthetic techniques are employed. The procedure can be performed in sedation with the application of local anesthetic and general anesthesia. When using local anesthetic sedation, the patient breathes spontaneously, general anesthesia maintains the respiratory tract with a laryngeal mask or an orotracheal tube. In the patient aged 57, body mass 94 kg, with regular pulmonary function according to ASA classifi cation, without known allergies, the EBUS diagnostic scan was indicated for increased lymph nodes in the mediastinum. Diagnostic EBUS is run on a remote site equipped with the Datex-Ohmeda S5 Aespire anesthetic device and the Philips IntelliVue MP60 monitor, and we adjusted the anesthetic process to the existing conditions. Heart rate, electrocardiogram, number of breaths, blood pressure, percentage of hemoglobin, oxygen saturation and pulse oximetry were monitored. Intravenous cannula was placed and infusion of 500 mL of 0.9% NaCl maintained. Following local anesthesia with 1-2 mL 1% lidocaine in the oropharyngeal area, the patient was sedated with midazolam (2.5 mg), n-fentanyl (5 mcg) and propofol (bolus 100 mg and continuous maintenance dose of 4 mg/min). After fl exible bronchoscopy through the nose for 5 min, the EBUS was continued through the mouth for 22 min. The diagnostic procedure took a total of 27 min. During anesthesia, the patient was respiratory and hemodynamically stable. The patient breathed spontaneously with the addition of air/oxygen mixture 1:1, with a modality of 700 mL maximum volume and maximum frequency of 33/min. Such modifi cation achieved satisfactory ventilation and oxygen saturation at the periphery of 94±4%. Systemic blood pressure was 157±7 mm Hg and diastolic pressure 78±9 mm Hg. Heart rate was 88±8 min. After completing the diagnostic procedure, the patient woke up neatly. Anesthesia was without complications

Die Abhandlung über den bei Osijek gefundenen römischen Meilenstein… Dissertatio / de / colvmna milliaria / ad / Eszekvm / reperta / … III. Fortsetzung

V. POGLAVLJE U ovom broju Osječkog zbornika objavljujemo V. poglavlje “Rasprave o Rimskom mijlokazu, pronađenom kod Osijeka prilikom izgradnje ceste 1777. godine od Matije Petra Katančića”. U ovom V. poglavlju Katančić govori o rimskim natpisima i značajnijim novcima pronađenim kod Osijeka do kraja 18. stoljeća. Ovo poglavlje je veoma značajno za arheologiju, numizmatiku i antičku povijest Osijeka, jer je njime autor udario znanstvene temelje za obradu zbirke novca i epigrafskih spomenika. Tijekom vremena brojni ostaci rimske Murse su nestali i raznešeni na sve strane, pa su nam ovi Katančićevi podaci dragocjen izvor, tim više što objašnjava natpise i daje mjesto nalaza Ovom raspravom Katančić se proslavio kao vrstan znanstvenik krajem 18. st. i ukazao europskoj javnosti na kulturnu veličinu svojega naroda. Ujedno smo tako završili cjeloviti prijevod Katančićeve rasprave — vidi: Osječki zbornik, 1987., br.18.-19-, str. 349-374; OZ, 1989., br. 20, str. 299-318, te ovaj broj. Tako omogućujemo široj javnosti da koristi tako značajne i vrijedne izvore hrvatske prošlosti. Bilo bi prikladnije da je rasprava objavljena u jednom broju ili zasebnoj knjižici, ali bolje i ovako nego nikako, na čemu hvala Muzeju Slavonije u Osijeku. I. nastavak—Osječki zbornik, 1987., 18-19, str. 349-374 II. nastavak— Osječki zbornik, 1989., 20, str. 299-318 III. nastavak — Osječki zbornik, 1991., 21, str. 51-76V. ABSCHNITT In diesem Sammelband wird der. V. Abschnitt der von Matija Petar Katancic verfaßten Abhandlung “Der im Jahre 1777 beim Straßenbau bei Osijek gefundene Meilenstein" veröffentlicht. In diesem V. Abschnitt behandelt Katancic die bis zum Ende des 18. Jhs. bei Osijek gefundenen römischen Inschriften und wichtigeren Münzen. Dieser Abschnitt ist für die Archäologie, Numismatik und antische Geschichte Osijek sehr bedeutend, denn dadurch schuf der Verfasser die wissenschaftlichen Grundlagen für die Bearbeitung der Münzensammlung und epigraphischen Denkmäler. Im Laufe der Zeit sind zahlreiche Überreste des römischen Mursas verschwunden oder nach allen Seiten verschleppt worden, so daß die von Katancic gesammelten Angaben eine reichhaltige Quelle darstellen, um so meh

Kinetic Study of Thermal Degradation of High-impact Polystyrene Nanocomposites with Different Flame Retardants using Isoconversional and Model Fitting Methods

The non-isothermal degradation of pure high-impact polystyrene (HIPS) and flame retarded HIPS nanocomposites was investigated in the temperature range 25–550 °C at four heating rates in an inert atmosphere. Three different phosphate and polyphosphate based flame retardants were used, while nanosilica and montmorillonite clay were used as nanofillers. Kinetic analysis was performed using isoconversional and model fitting non-linear regression method. Activation energy (Ea) was determined by isoconversional methods of Friedman and Kissinger-Akahira-Sunose while true kinetic triplets (Ea, A, f(α)) were determined by one step and two-step non-linear regression with various reactions mechanisms. It was found that flame retarded samples exhibit complex degradation which cannot be satisfactorily described by single reaction model fitting. Instead, when each distinctive degradation step was modelled individually it was possible to obtain good fit with Reaction order and Avrami-Erofeev proposed mechanisms while the same was not possible for Diffusion and Autocatalytic mechanisms. This work is licensed under a Creative Commons Attribution 4.0 International License

THE IMPORTANCE OF ANESTHESIA IN DIAGNOSTIC TESTS OF ENDOBRONCHIAL ULTRASOUND

Prikazan je mogući anestezijski postupak za dijagnostički endobronhijski ultrazvuk. (EBUS). EBUS je specifi čna pretraga za dijagnostiku novonastale hilarne i/ili medijastinalne limfadenopatije te tumora pluća. Anestezija olakšava izvođenje ovog dijagnostičkog postupka bolesniku i liječniku. Iz dosadašnjih studija vidljivo je da su u primjeni različite tehnike anestezije. Postupak se može izvesti u sedaciji primjenom lokalnog anestetika i općoj anesteziji. Kod primjene sedacije lokalnim anestetikom bolesnik diše spontano, a u općoj anesteziji se dišni put održava laringealnom maskom ili orotrahealnim tubusom. Bolesniku u dobi od 57 godina, tjelesne težine (TM) 94 kg, ASA I (The American Society of Anesthesiologists), uredne plućne funkcije, bez poznatih alergija, indicirana je dijagnostička pretraga EBUS zbog povećanih limfnih čvorova u medijastinumu. Dijagnostička pretraga EBUS izvodi se na udaljenom radilištu koji je opremljen anesteziološkim uređajem Datex-Ohmeda S5 Aespire 1990. godine i monitorom Philips IntelliVue MP60. te smo anestezijski postupak prilagodili postojećim uvjetima. Monitorira se srčana frekvencija, elektrokardiogram (EKG), broj respiracija, krvni tlak, te postotak zasićenja hemoglobina kisikom pulsnim oksimetrom. Postavljena je intravenska kanila čija se prohodnost održava infuzijom 500 mL 0,9 % NaCl. Nakon lokalne anestezije 1-2 mL 1 %-tnim lidokainom orofaringealnog područja bolesnik je sediran midazolamom (2,5 mg), n-fentanilom (5 mcg) te propofolom (bolus 100 mg i doza održavanja kontinuirano 4 mg /min). Nakon fl eksibilne bronhoskopije kroz nos od 5 minuta nastavlja se EBUS kroz usnik u trajanju od 22 minute. Dijagnostički postupak ukupno je trajao 27 minuta. Za vrijeme anestezije bolesnik je bio respiracijski i hemodinamski stabilan, diše spontano uz suplementaciju smjese zrak/kisik 1 : 1 volumnim modalitetom maksimalnog volumena 700 mL i frekvencije maksimalno 33/min. S takvom modifi - kacijom se postigla zadovoljavajuća ventilacija i zasićenost kisikom koja je na periferiji iznosila 94±4 %. Sistolički krvni tlak je iznosio 157±7 mm Hg, a dijastolički 78±9 mm Hg. Srčana frekvencija bila je 88±8/min. Bolesnik se nakon učinjenog dijagnostičkog zahvata uredno probudio. Anestezija je protekla bez komplikacija.A possible anesthetic procedure for diagnostic endobronchial ultrasound (EBUS) is presented. EBUS is a specifi c search for the diagnosis of newly emerged hilar and/or mediastinal lymphadenopathy and lung tumors. Anesthesia facilitates the performance of this diagnostic procedure for the patient and the physician. From previous studies, it is apparent that various anesthetic techniques are employed. The procedure can be performed in sedation with the application of local anesthetic and general anesthesia. When using local anesthetic sedation, the patient breathes spontaneously, general anesthesia maintains the respiratory tract with a laryngeal mask or an orotracheal tube. In the patient aged 57, body mass 94 kg, with regular pulmonary function according to ASA classifi cation, without known allergies, the EBUS diagnostic scan was indicated for increased lymph nodes in the mediastinum. Diagnostic EBUS is run on a remote site equipped with the Datex-Ohmeda S5 Aespire anesthetic device and the Philips IntelliVue MP60 monitor, and we adjusted the anesthetic process to the existing conditions. Heart rate, electrocardiogram, number of breaths, blood pressure, percentage of hemoglobin, oxygen saturation and pulse oximetry were monitored. Intravenous cannula was placed and infusion of 500 mL of 0.9% NaCl maintained. Following local anesthesia with 1-2 mL 1% lidocaine in the oropharyngeal area, the patient was sedated with midazolam (2.5 mg), n-fentanyl (5 mcg) and propofol (bolus 100 mg and continuous maintenance dose of 4 mg/min). After fl exible bronchoscopy through the nose for 5 min, the EBUS was continued through the mouth for 22 min. The diagnostic procedure took a total of 27 min. During anesthesia, the patient was respiratory and hemodynamically stable. The patient breathed spontaneously with the addition of air/oxygen mixture 1:1, with a modality of 700 mL maximum volume and maximum frequency of 33/min. Such modifi cation achieved satisfactory ventilation and oxygen saturation at the periphery of 94±4%. Systemic blood pressure was 157±7 mm Hg and diastolic pressure 78±9 mm Hg. Heart rate was 88±8 min. After completing the diagnostic procedure, the patient woke up neatly. Anesthesia was without complications

Influence of Titanium Dioxide Preparation Method on Photocatalytic Degradation of Organic Dyes

Titanium catalysts (TiO2) were synthesized by three different methods. Their photocatalytic activity was validated through photodegradation of Reactive Red 45 (RR45) azo dye and Acid Blue 25 (AB25) anthraquinone dye in an aqueous solution under UV irradiation. TiO2 photocatalysts were characterized by FTIR, XRD and SEM. Photosensitivity and TiO2 activity range were characterized by UV/Vis spectroscopy. Photocatalytic validation has been made by way of determining the degree of RR45 and AB25 removal. TOC was determined as a measure of the mineralization of RR45 and AB25 by photocatalysis. The stability of TiO2 catalysts and a possibility of using them in consecutive photocatalysis cycles have also been studied. The results show that the photocatalytic efficiency depends on the crystal structure of TiO2. The size of crystallites depends on synthesis conditions. From the results of photocatalytic efficiency it is concluded that the chemical interaction between a catalyst and a dye strongly depends on the dye chemical structure

Peripheral Arterial Catheter Related Infections in the Neurosurgical Intensive Care Unit

Intravascular device infections could be serious complications with significant contributable morbidity and mortality. The aim of this prospective clinical study is to demonstrate the infection rate related to peripheral arterial catheters and their clinical significance in neurosurgical intensive care unit (ICU) patients. After removal, all arterial catheter tips were cultivated by semiquantitative method and clinical data were collected. During a period of two years, 186 arterial catheters were placed in 105 neurosugical ICU patients. In 6 cases (3.2%) infection was presumably related to the arterial catheter. The rate of such probable catheter related infections was found to be 5/1000 catheter days. The isolated microorganisms were: Methicillin resistant Staphylococcus epidermidis (MRSE) in 4 cases, Corynebacterium species and Candida albicans each in one case respectively. Thirteen cases (7.0%) were interpreted as contamination and one as colonization. An association was found between the presence of infection from different sources and significant bacterial growth on the catheter. Patients with positive catheter culture had a significantly longer ICU stay, more cumulative catheter days, and a higher mortality rate than those with sterile catheters. We can conclude that the rate of probable peripheral arterial catheter related infection is low. A higher mortality rate in patients who experienced probable catheter related infection does not seem to be a consequence of the aforementioned infection. A more suitable explanation would be that patients with nosocomial infections and higher mortality risk have prolonged ICU stays. There is an increased chance of developing a catheter related infection in those patients who have more cumulative catheter days

Od makro do mikroplastike; utjecaj fotooksidativne degradacije

The impact of plastic waste on the environment, human health, and ecosystems is one of the most important issues today. Once released into the environment, plastic waste is exposed to various stress factors that can lead to a reduction in its structural integrity and consequently to its fragmentation into smaller pieces. In this work, the effects of simulated UV aging on the surface properties and fragmentation of high-density polyethylene (HDPE) films were studied. HDPE films were prepared from pristine polymer granules, and aged for 14, 28, and 42 days under artificial UV irradiation. The samples were characterised before and after each irradiation period to inspect structural and surface changes. FTIR spectra revealed the appearance of carbonyl (C=O) and carbon-oxygen (C−O, O−C=O, C−O−O−) groups due to photodegradation of HDPE. The change in surface polarity with UV irradiation time was determined by measuring the water contact angle, while the surface morphology was analysed using a SEM microscope. The results revealed a significant increase in carbonyl index, increased hydrophilicity, and increased brittleness resulting from a high degree of photodegradation after 28 and 42 days of UV irradiation. The different particle size distribution yielded upon grinding indicated that aged HDPE films are more prone to fragmentation into micro-sized particles.Utjecaj plastičnog otpada na okoliš, ljudsko zdravlje te ekosustav jedno je od najvažnijih pitanja današnjice. Nakon što se ispusti u okoliš, otpad je izložen različitim okolišnim utjecajima koji mogu dovesti do narušavanja cjelovitosti strukture, a posljedično i do fragmentacije na manje dijelove. U ovom su radu istraživani učinci simuliranog UV starenja na površinska svojstva i fragmentaciju filmova polietilena visoke gustoće (HDPE). HDPE filmovi pripremljeni su od polimernih granula te potom stareni 14, 28 i 42 dana pod utjecajem simuliranog UV zračenja. Uzorci su karakterizirani prije te nakon svakog razdoblja ozračivanja da bi se utvrdile strukturne i površinske promjene. Na temelju FTIR spektara ustanovljena je pojava karbonilnih (C=O) i ugljiko-kisikovih (C−O, O−C=O, C−O−O−) skupina kao rezultat fotodegradacije HDPE-a. Promjena polarnosti površine s vremenom UV ozračivanja određena je mjerenjem kontaktnog kuta, dok je morfologija površine analizirana SEM mikroskopom. Rezultati su ukazali na znatno povećanje karbonilnog indeksa te hidrofilnosti, kao i povećanu lomljivost kao rezultat visokog stupnja fotodegradacije nakon 28 i 42 dana UV zračenja. Različita raspodjela veličine čestica dobivena mljevenjem materijala upućuje na to da su stareni HDPE filmovi skloniji fragmentaciji u čestice mikroveličina