Recently, due to the corrosion problem in the petroleum industry and the usage of commercial corrosion inhibitors, which, when released untreated into the environment, are considered to be ...environmentally unfriendly, green corrosion inhibitors are being researched. In this paper, the results of dandelion-root-extract testing as a green corrosion inhibitor for carbon steel in simulated brine solution saturated with carbon dioxide (CO2) are shown. The extract’s inhibition efficiency in static and flow conditions was determined by using potentiodynamic polarization with Tafel extrapolation and electrochemical-impedance-spectroscopy methods. In static conditions, the extract was tested at different concentrations. A maximum inhibition efficiency of 98.37% in static conditions at an extract concentration of 12 mL/L and 82.80% in flow conditions at a concentration of 14 mL/L was achieved. Additionally, for the most efficient dandelion-root-extract concentration (12 mL/L), the biodegradability and toxicity were determined. A biodegradability of 0.96 and a toxicity of 2.38% was achieved. Based on the obtained results of the conducted laboratory measurements, it can be concluded that dandelion-root extract has significant potential in terms of its use as a green corrosion inhibitor for carbon steel in a CO2-saturated brine solution.
Due to issues with the corrosion problem in the petroleum industry and the use of less ecologically acceptable corrosion inhibitors, great emphasis, within research on corrosion inhibitors, is now ...being put on green corrosion inhibitors (GCIs). In this study, Lady’s mantle flower extract (LMFE) has been observed as a plant-based GCI for carbon steel in a simulated CO2-saturated brine solution. The effectiveness of the inhibitor in static and flow conditions has been determined using potentiodynamic polarization with Tafel extrapolation and electrochemical impedance spectroscopy (EIS). In static conditions, the inhibitor has been tested at concentrations from 1 g/L to 5 g/L with an increment of 1 g/L per measurement, while, in dynamic (flow) conditions, the inhibitor has been tested at concentrations from 3 g/L to 6 g/L with an increment of 1 g/L per measurement. All measurements were performed at room temperature. EIS and potentiodynamic polarization methods showed that LMFE achieves maximum effectiveness in protecting carbon steel from corrosion when added at a concentration of 4 g/L in static conditions and at a concentration of 5 g/L in flow conditions. The test methods proved that the inhibitory effectiveness of LMFE is greater than 90% in both test conditions (static and flow). The inhibitor efficiency was attributed to the adsorption of LMFE on the carbon steel surface, which was demonstrated by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). A biodegradability of 0.96 and a toxicity of 19.34% for LMFE were determined. The conducted laboratory tests indicate that LMFE could be used as an effective corrosion inhibitor for CO2 carbon steel corrosion.
In this paper, preliminary studies of ten different plant extracts as potential corrosion inhibitors of carbon steel were examined. For each extract, the concentration range in which it shows ...anti-corrosion action was first determined, and then the most effective concentration was determined for each extract. The tests were performed in a brine solution saturated with CO2 at room temperature. The aim of this study was to isolate extracts with high effectiveness and subsequent electrochemical and surface methods to determine the mechanism of inhibitory action. For this purpose, potentiodynamic polarization was performed with Tafel extrapolation. Among all the tested extracts, lady’s mantle (92.17%) and dandelion root (95.07%) stood out with their effectiveness. Both tested extracts showed the behaviour of a mixed corrosion inhibitor with a dominant influence on the anode process.
Due to issues with the corrosion problem in the petroleum industry and the use of less ecologically acceptable corrosion inhibitors, great emphasis, within research on corrosion inhibitors, is now ...being put on green corrosion inhibitors (GCIs). In this study, Lady’s mantle flower extract (LMFE) has been observed as a plant-based GCI for carbon steel in a simulated COsub.2-saturated brine solution. The effectiveness of the inhibitor in static and flow conditions has been determined using potentiodynamic polarization with Tafel extrapolation and electrochemical impedance spectroscopy (EIS). In static conditions, the inhibitor has been tested at concentrations from 1 g/L to 5 g/L with an increment of 1 g/L per measurement, while, in dynamic (flow) conditions, the inhibitor has been tested at concentrations from 3 g/L to 6 g/L with an increment of 1 g/L per measurement. All measurements were performed at room temperature. EIS and potentiodynamic polarization methods showed that LMFE achieves maximum effectiveness in protecting carbon steel from corrosion when added at a concentration of 4 g/L in static conditions and at a concentration of 5 g/L in flow conditions. The test methods proved that the inhibitory effectiveness of LMFE is greater than 90% in both test conditions (static and flow). The inhibitor efficiency was attributed to the adsorption of LMFE on the carbon steel surface, which was demonstrated by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). A biodegradability of 0.96 and a toxicity of 19.34% for LMFE were determined. The conducted laboratory tests indicate that LMFE could be used as an effective corrosion inhibitor for COsub.2 carbon steel corrosion.
Prema diskonekcijskoj hipotezi poremećena interhemisferalna komunikacija u središnjem živčanom susutavu može se
povezati s razvojem shizofrenog poremećaja. Na korpusu kalozumu oboljelih osoba ...pronađene su morfološke i funkcionalne
promjene, ali rezultati su još uvijek nedoslijedni. Prikazi pacijenata s agenezom korpusa kalozuma i shizofrenijom
pružaju priliku za daljnje razumijevanje te povezanosti. U radu je prikazana pacijentica sa sniženim intelektualnim sposobnostima
kod koje je u adolecenciji verificiran prolazni psihotični poremećaj, a u odrasloj dobi došlo je do postupnog
pada sveukupne kvalitete osobnog ponašanja, povlačenja iz socijalnih kontakata, gubitka interesa, uz nemotivirano i
dezorganizirano ponašanje, zanemarivanje higijene te vjerojatne slušne obmane osjetila. Tijekom obrade ustanovljena
je potpuna ageneza korpusa kalozuma s pratećim proširenjem moždanih komora. Parcijalni terapijski pomak postignut
je uz terapiju malim dozama olanzapina.
Ancient DNA research in the past decade has revealed that European population structure changed dramatically in the prehistoric period (14,000-3000 years before present, YBP), reflecting the ...widespread introduction of Neolithic farmer and Bronze Age Steppe ancestries. However, little is known about how population structure changed from the historical period onward (3000 YBP - present). To address this, we collected whole genomes from 204 individuals from Europe and the Mediterranean, many of which are the first historical period genomes from their region (e.g. Armenia and France). We found that most regions show remarkable inter-individual heterogeneity. At least 7% of historical individuals carry ancestry uncommon in the region where they were sampled, some indicating cross-Mediterranean contacts. Despite this high level of mobility, overall population structure across western Eurasia is relatively stable through the historical period up to the present, mirroring geography. We show that, under standard population genetics models with local panmixia, the observed level of dispersal would lead to a collapse of population structure. Persistent population structure thus suggests a lower effective migration rate than indicated by the observed dispersal. We hypothesize that this phenomenon can be explained by extensive transient dispersal arising from drastically improved transportation networks and the Roman Empire's mobilization of people for trade, labor, and military. This work highlights the utility of ancient DNA in elucidating finer scale human population dynamics in recent history.
The aim of this work was to assess the biopotential of the young inflorescence tissues of
,
and
in order to evaluate the possibility of their application in the food industry, and to provide a ...polyphenolic fingerprint for their quality control. The contents of different bioactive compounds and their antioxidant capacities were spectrophotometrically measured, the main phenolic compounds were identified and quantified using LC-DAD-MS, the antidiabetic potential was determined using α-amylase and α-glucosidase inhibition assays, the anti-inflammatory potential was determined using a 5-lipoxygenase inhibition assay, and the cytotoxicity was determined by MTT assay. Using one-way ANOVA, principal component analysis, hierarchical clustering and Pearson's correlation coefficient, the relations between the samples, and between the samples and the measured parameters, were revealed. In total, 77 compounds were identified. The concentration of sugars was low in
at 1.56 ± 0.08 mg/g DW. The most effective sample in the inhibition of antidiabetic enzymes and anti-inflammatory 5-lipoxygenase was
. The inhibition of α-glucosidase was strongly positively correlated with the total and condensed tannins, procyanidin dimers and procyanidin tetramer, and was very strongly correlated with chlorogenic acid. In α-amylase inhibition,
and
'Kiku Shidare Zakura' were equally efficient to the standard inhibitor, maltose. The most effective in the growth and proliferation inhibition of HepG2, HCT116 and HaCaT cells was
. The results suggest
,
and
inflorescences as functional food ingredients.
To develop and test the psychometric characteristics of a questionnaire measuring attitudes toward plagiarism.
Participants were 227 undergraduates and graduate students (128 women and 99 men) from ...three Croatian universities, with a median age of 21 years (range 18 to 48). Research was conducted from March to June 2009. For the purpose of construction of the first version of the questionnaire, 67 statements (items) were developed. The statements were based on the relevant literature and were developed following rules and recommendations for questionnaire writing, and 36 items were chosen for final validation. Factor analysis was used to find out the factor structure of the questionnaire and to measure construct validity.
The final version of the questionnaire consisted of 29 items divided into a three-factor structure: factor I - positive attitude toward plagiarism (12 items); factor II - negative attitude toward plagiarism (7 items); and factor III - subjective norms toward plagiarism (10 items). Cronbach alpha was calculated to confirm the reliability of the scale: factor I - alpha=0.83; factor II - alpha=0.79; and factor III - alpha=0.85. Correlations between factors were: -0.37 between I and II, -0.41 between I and III, and +0.31 between II and III.
Attitudes Toward Plagiarism questionnaire was developed, with good psychometric characteristics. It will be used in future research as a standardized tool for measuring attitudes toward plagiarism.