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Photoluminescence imaging under sunlight excitation has in the recent years been proposed as a promising inspection technique of field-installed photovoltaic modules. Virtually, all studies have been conducted in full sunlight and clear sky conditions. A study in which photoluminescence images had been acquired at an irradiance level below 100 W m−2 using the lock-in technique has shown the potential of these images with respect to defect analysis. Additionally, as on-site measurement techniques are subject to weather conditions, it would be favorable to extend the applicability of photoluminescence imaging to a wider range of irradiance levels. A method for photoluminescence imaging which does not use the lock-in technique for the purpose of filtering of sunlight was proposed recently. The present study extends the application of this approach to diffuse irradiance conditions. We demonstrate that the method gives valuable information about the modules also in the case of image acquisition under diffuse global in-plane irradiance as low as 40 W m−2. Photoluminescence images acquired under low irradiance are comparable to electroluminescence images acquired at 10% of short-circuit current. Photoluminescence imaging has also been conducted successfully from the rear of bifacial modules in these illumination conditions. [ABSTRACT FROM AUTHOR]

Photoluminescence imaging of field-installed photovoltaic modules has the potential to be a high throughput on-site inspection technique. A contribution to this development is a noninvasive photoluminescence imaging method that has been proposed recently. It is based on acquiring images during a progressing current–voltage curve sweep, resulting in a detection of a continuously changing photoluminescence signal. From this follows the necessity to employ an alternative algorithm based on the Pearson correlation coefficient, which will contribute to efficient, unsupervised image processing and, thus, easier (in real-time) implementation. The new algorithm separates photoluminescence from the reflected sunlight, similar to the conventional subtraction algorithm. However, it is robust to varying solar irradiance and can process the photoluminescence signal emitted from multiple asynchronized strings. We predict that it will enable unsupervised real-time surveillance and detection of functional anomalies at a low computational cost. It is also more sensitive at segmenting ground-reflected photoluminescence. [ABSTRACT FROM AUTHOR]

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Silver powders produced by both electrochemical (galvanostatic (DC) and potentiostatic (POT) regimes of electrolysis) and chemical processes were examined by scanning electron microscope, and particle size distribution (PSD) of the obtained particles was done. In the DC regime, the current densities of –14.4 mA cm-2 for the nitrate (NIT; powder denoted with DC(NIT)) and –13.05 mA cm-2 for the ammonium (AM; DC(AM)) electrolytes were applied. In the POT regime, the used overpotentials were –90 mV (NIT(90)) and –150 mV (NIT(150)) for the nitrate, and –625 mV (AM(625)) and –925 mV (AM(925)) for the ammonium electrolytes. Reduction with hydrazine was used for chemical synthesis (powder denoted with HYD). On the basis of SEM and PSD analysis, Ag powders were grouped into three groups. In the first group DC(AM), AM(925) and HYD powders with the (8.4–8.9 %) volume ratios were placed. In the second group were AM(625) and DC(NIT) powders with the (6.5–6.6 %) volume ratios. NIT(90) and NIT(150) powders with the volume ratios of (5.2–5.7 %) made the third group. The obtained volume ratios were correlated with the morphology of synthesized particles in order to perceive advantages and lacks of powder production via electrochemical and chemical routes.

Quality management is a continuous and dynamic approach to business that seeks to increase the quality, competitiveness and productivity of the organization through the process of continuous improvement of the quality of products, services, processes, people and the environment. The production of plastic injection molding tools is characterized by single production and high product prices. Mistakes in the process of development, design and production of tools most often lead to high costs, non–fulfillment of agreed delivery dates and loss of image with the customer. Because of this, the manufacturer should establish an effective quality management system in its processes, and especially the quality control subsystem. In modern production, product quality control is indispensable and is imposed as a mandatory function of the organization. Controlling and testing of the product during the process of its creation and delivery to the customer is carried out according to pre–defined control points and characteristics for control. These elements are defined in the process of design and technological preparation and are an integral part of the appropriate control documentation. Adequate application of control documentation improves product quality, identifying sources of variation in individual processes and establishing controls for their monitoring. This has the effect of increasing customer satisfaction, reducing waste and improving the financial results of the business. The aim of this paper is to analyze the processes of making plastic injection molding tools and to define and implement the control documentation required for their production. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Healthcare professionals lack the knowledge about the impact of formulations on treatment effectiveness. This is further complicated by the existence of dietary supplements containing the same active pharmaceutical ingredients (API) as drug formulations [e.g., alpha-lipoic acid (ALA)], to which the strict formulation testing requirements do not apply. This research aimed to compare ALA-containing drugs and dietary supplements through the determination of uniformity of content, disintegration time and dissolution rates. MATERIALS AND METHODS: A total of seven different ALA formulations (5 dietary supplements, 2 drugs) were tested for uniformity of content, disintegration time and dissolution rates. All tests were performed in accordance with the 10th European Pharmacopoeia. ALA was determined spectrophotometrically. RESULTS: Uniformity of content testing revealed larger variations of ALA content in three formulations of dietary supplements. Dissolution curves generated at 50 and 100 rpm differed significantly. Testing requirements were met only by one dietary supplement at 50 rpm, and one drug and two dietary supplements at 100 rpm. Disintegration testing showed limited impact on the release kinetic of ALA, as opposed to formulation type. CONCLUSIONS: Considering the lack of regulation on dietary supplement formulations and the variable success of them conforming to pharmacopoeial requirements, it is an imperative for stricter regulations on the dietary supplements' formulations to be imposed globally. [ABSTRACT FROM AUTHOR]

Treatment of wastes and leachate evolved in landfills is today an imperative due to rigorous environmental protection legislation. In this work, biodegradation of the organic fraction in tobaccowaste leachate was studied. Experiments were carried out in a batch reactor at initial concentra tion of activated sludge of 3.03 g dm–3 and different initial concentrations of organic matter in leachate, expressed as COD, which ranged from 0.5 to 3.0 g dm–3 . The working volume of the reactor (Fig. 1) was 7 dm3 within the cylindrical porous liner and it was filled with the suspension of leachate and activated sludge . The liner was designed such that it did not allow activated sludge to pass through. Continuous up-flow aeration was provided by a membrane pump. The temperature during the biodegradation process was 23 ± 2 °C. Dissolved oxygen, pH and temperature in reactor were monitored continuously by probes connected to a remote meter. Toxicity of leachate was performed by toxicity test using marine bacteria Vibrio fischeri before starting with the biodegradation in the batch reactor. The obtained results showed that effective concentration of leachate is EC 50 = 1.6 g dm–3 and toxicity impact index is TII50 = 9.99, meaning that untreated leachate must not be discharged into the environment before treatment. The results of the biodegradation process of leachate in batch reactor are presented in Table 1 and Fig. 2. The ratio γXv/γX was almost constant throughout the experiments and ranged from 0.69 do 0.73. This implies that the concentration of biomass remained unchanged during the experiments, and average yield was 5.26 %. The important kinetic and stoichiometric parameters required for performance of the biological removal process, namely the Y, Ks, Kd, and μmax were calculated from the batch experiments (Table 2). The experimental results of the influence of initial substrate concentrations on substrate degradation rate, and influence of initial substrate concentrations on biomass growth rate in comparison with Monod model are presented in Figs. 3 and 4. These results suggest that selected model de scribes well the biodegradation process of leachate in batch reactor. Microscopic examination of activated sludge showed that flocs were healthy and compact, with simultaneous formation of young flocs (Table 3, Figs. 5a and 5b). Figure 6 presents the decrease in organic matter in the leachate and increase in activated sludge concentration within two days of biodegradation during which activated sludge showed strong ability to degrade organic matter, while process efficiency (Fig. 7) was approximately 80.3 %.

The influence of the presence of Sb atoms, as foreign metal atoms in anode copper, on kinetics, and, on the mechanism of anodic dissolution and cathodic deposition of copper in acidic sulfate solution has been investigated. The galvanostatic single-pulse method has been used. Results indicate that presence of Sb atoms in anode copper increase the exchange current density as determined from the Tafel analysis of the electrode reaction. It is attributed to the increase of the crystal lattice parameter determined from XRD analysis of the electrode material.

Anodic oxidation of the natural mineral chalcopyrite from the Bor ore deposit has been studied by cyclic voltammetry in pure sulfuric acid solutions. At the obtained voltammograms, the appearance of peaks at certain potential regions was identified and found to be much less pronounced than those previously reported in the literature. The voltammetric kinetic analysis confirmed that two-electron exchange electrochemical reactions occur. The explanation for this somewhat different electrochemical behavior of natural chalcopyrite compared to the concentrates widely used in studies of this mineral will also be given.

OBJECTIVE: In this study, we analyzed breast cancer mortality data overall and by age groups in women in Montenegro, to determine if there were any changes in trend for period 1990-2018. MATERIALS AND METHODS: The study gathered data on breast cancer mortality in Montenegro obtained from Vital Registration System. Annual data on breast cancer mortality were extracted for period 1990-2018 and analyzed using World Standard Population age-standardized and age-specific rates and Joinpoint regression. RESULTS: In 2018 in Montenegro, breast cancer accounted for 4.64% of all deaths in women and for 19.78% of all cancer deaths in women. In terms of total cancer mortality, it ranked first among women. Age-standardized rates ranged from 11.41/100,000 in 1990 to 20.46/100,000 in 2016. Joinpoint regression showed no one joinpoint for the entire population of all women and age groups. In the observed period, breast cancer mortality rates significantly increased in the women in Montenegro [average annual percentage change (AAPC) = 1.44%; 95% confidence interval (CI): 0.9-2.0]. The most affected age group was 55-64 years. CONCLUSIONS: There is a growing breast cancer mortality trend in Montenegro. It is necessary to create specific programs for urgent action, in order to reduce this undesirable trend. At the same time, support from the competent institutions is needed for increasing screening coverage and better prevention of breast cancer in the target population. [ABSTRACT FROM AUTHOR]

Copyright of Agriculture / Poljoprivreda is the property of Josip Juraj Strossmayer University of Osijek, Faculty of Agriculture in Osijek and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)