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Productivity and flower quality of different pot marigold (Calendula officinalis L.) varieties on the compost produced from medicinal plant waste
No full textThis article describes still insufficiently known technology of pot marigold cultivation with the compost produced from the organic waste of the processing of medicinal plants. For the first time the application was analyzed of different amounts of compost (control – without compost, 2, 10 and 30 kg/m2) on the morphological, productive and qualitative parameters of two pot marigold varieties (Domaći oranž and Plamen Plus). During the five-year period, the best results in both tested pot marigold varieties were achieved with the 30 kg/m2 compost application. The yield of dry flower was higher for the Domaći oranž pot marigold variety fertilized with 30 kg/m2 compost (1957.4 kg/ha) compared with the Plamen Plus variety (451.1 kg/ha). A significantly higher fresh flower yield of the Domaći oranž variety greatly influenced the increase in the quantities of examined quality parameters (total carotenoids, total phenolic, total flavonoids, and DPPH reduction), whose content was higher in the Plamen Plus variety. The artificial neural network model, was built applying the Broyden-Fletcher-Goldfarb-Shanno algorithm, exerted the adequate forecasting abilities for the productivity and quality of pot marigold flowers and the influence of compost material, produced from medicinal plants waste (R2 was 0.837 for the training period). This research demonstrates that it is possible to use organic waste obtained in the processing of medicinal plants, supporting the effectiveness of a circular economy model in the cultivation of pot marigold
Green Infrastructure Designed through Nature-Based Solutions for Sustainable Urban Development
No full textWith the goal of enhancing the quality of the environment, urban green infrastructure (UGI) is an essential element in sustainable cities, and nature-based solutions (NBS) are being carried out as new infrastructure solutions that increase the resilience of cities. In this research, the method of theoretical analysis and the content analysis as the basic fact-gathering technique was applied to answer to following questions: What are the hindrances and bottlenecks in implementing NBS? Are the current decision-making mechanisms helping NBS get in route to shape cities? Is there any binding policy in practice that promotes NBS? In Belgrade is planned Type 3 of the degree of intervention/level and engineering type-Creation and new ecosystem management in the classifications of intensive urban green space management; urban planning strategies; urban water management; ecological restoration of degraded terrestrial ecosystems; and restoration and creation of semi-natural water bodies and hydrographic networks. In the future, it is essential to implement policies and incentives on national, regional, and local scales that help encourage the usage of NBS in the development of urban infrastructure
Energy Potentials of Agricultural Biomass and the Possibility of Modelling Using RFR and SVM Models
No full textAgricultural biomass is one of the most important renewable energy sources. As a byproduct of corn, soybean and sunflower production, large amounts of biomass are produced that can be used as an energy source through conversion. In order to assess the quality and the possibility of the use of biomass, its composition and calorific value must be determined. The use of nonlinear models allows for an easier estimation of the energy properties of biomass concerning certain input and output parameters. In this paper, RFR (Random Forest Regression) and SVM (Support Vector Machine) models were developed to determine their capabilities in estimating the HHV (higher heating value) of biomass based on input parameters of ultimate analysis. The developed models showed good performance in terms of HHV estimation, confirmed by the coefficient of determination for the RFR (R-2 = 0.79) and SVM (R-2 = 0.93) models. The developed models have shown promising results in accurately predicting the HHV of biomass from various sources. The use of these algorithms for biomass energy prediction has the potential for further development
Recovery of Biologically Active Compounds from Stinging Nettle Leaves Part II: Processing of Exhausted Plant Material after Supercritical Fluid Extraction
No full textStinging nettle (Urtica dioica L.) is one fantastic plant widely used in folk medicine, pharmacy, cosmetics, and food. This plant's popularity may be explained by its chemical composition, containing a wide range of compounds significant for human health and diet. This study aimed to investigate extracts of exhausted stinging nettle leaves after supercritical fluid extraction obtained using ultrasound and microwave techniques. Extracts were analyzed to obtain insight into the chemical composition and biological activity. These extracts were shown to be more potent than those of previously untreated leaves. The principal component analysis was applied as a pattern recognition tool to visualize the antioxidant capacity and cytotoxic activity of extract obtained from exhausted stinging nettle leaves. An artificial neural network model is presented for the prediction of the antioxidant activity of samples according to polyphenolic profile data, showing a suitable anticipation property (the r(2) value during the training cycle for output variables was 0.999)
Structural and Functional Picosecond Laser Modification of the Nimonic 263 Superalloy in Different Environmental Conditions and Optimization of the Irradiation Process
No full textIn this experimental study, picosecond laser treatment was performed on a nickel-based superalloy Nimonic 263, aiming to investigate the surface effects induced by irradiation in different atmospheric conditions and, concerning changes in surface composition, regarding the possibility for improvement of its functionality. Besides the varying laser parameters, such as a number of pulses and pulse energy, environmental conditions are also varied. All surface modifications were carried out in standard laboratory conditions and a nitrogen- and argon-rich atmosphere. The resulting topography effects depend on the specific laser treatment and could be categorized as increased roughness, crater formation, and formation of the laser-induced periodic surface structures (LIPSS). Changes in the chemical surface composition are distinguished as the potential formation of the protective oxides/nitrides on the sample surface. Numerous characterization techniques analyse the resulting effects on the topography and surface parameters. The multi-response parametric optimization of the picosecond laser process was performed using an advanced statistical method based on Taguchi's robust parameter design. Finally, the optimal parameter conditions for Nimonic 263 modification are suggested
Thermophoresis or When Small Objects Meet Temperature Gradient: Numerous Applications
No full textThis mini review discusses the phenomenon of thermophoresis, also known as the thermophoretic effect. Thermophoreticeffect arises from the combination of a temperature gradient and particles of very small dimensions, on the order of magnitudeof the mean free path of the molecules of the surrounding gas. Despite being a little-known effect, it is critical to many physicaland chemical processes and for characterising the properties of nanostructured materials that could be used in industry forsensing applications. A description and definition of otherwise very similar thermophoresis terms is provided, as well as a briefoverview of the literature on this topic, with a focus on research in the twenty-first centur
The role of Gentiana lutea extracts in reducing UV-induced DNA damage
No full textUltraviolet (UV) radiation can result in DNA damage, mainly through direct formation of pyrimidine dimers and generation of reactive oxygen species, which can lead to the skin disorders including cancer. In accordance with this, the use of natural antigenotoxins and/or antioxidants could contribute to human health protection. Considering that plants are rich in both, the aim of this study was to investigate UV-protective and antioxidative properties of yellow gentian (Gentiana lutea), being well established in pharmacopeias and traditional medicine. Tested extracts were derived from root and shoot of the in vitro cultivated plants. Prescreening of the genotoxic properties of UVC, UVA, and the extracts, as well as the extracts' antigenotoxicity were estimated by applying alkaline comet assay on normal fetal lung fibroblast (MRC-5) and human melanoma cells (Hs 294T). Antioxidant potential was tested in ferrous ions chelating ferric reducing antioxidant power and cupric reducing antioxidant capacity assays. Genotoxicity testing, which revealed moderate DNA-damaging potential of root extract on MRC-5 cells and high genotoxicity of shoot extract on both cell lines, pointed out nongenotoxic concentrations that could be used in antigenotoxicity assay. Doses of 63 and 3 J/cm(2) for UVC and UVA, respectively, were established for antigenotoxicity study, since they induced sufficient DNA damage without notable cytotoxicity. Results of antigenotoxicity revealed strong protective effect of both extracts against UVC (the highest inhibitions 58% and 47%) and UVA (the highest inhibitions 69% and 60%), in Hs 294T and MRC-5 cells, respectively. Study of the antioxidative properties demonstrated stronger activity of shoot extract. Results obtained proved to be encouraging but further research of the UV-protective role of Gentiana lutea extracts and underlying molecular mechanisms is recommended
Screening of Native Trichoderma Species for Nickel and Copper Bioremediation Potential Determined by FTIR and XRF
No full textSoil pollution with heavy metals is a serious threat to the environment. However, soils polluted with heavy metals are considered good sources of native metal-resistant Trichoderma strains. Trichoderma spp. are free-living fungi commonly isolated from different ecosystems, establishing endophytic associations with plants. They have important ecological and biotechnological roles due to their production of a wide range of secondary metabolites, thus regulating plant growth and development or inducing resistance to plant pathogens. In this work we used indigenous Trichoderma strains that were previously isolated from different soil types to determine their tolerance to increased copper and nickel concentrations as well as mechanisms of metal removal. The concentrations of bioavailable metal concentrations were determined after extraction with diethylene-triamine pentaacetate (DTPA)-extractable metals (Cd, Cr, Co, Cu, Pb, Mn, Ni, and Zn) from the soil samples by inductively coupled plasma-optical emission spectrometry (ICP-OES). Two indigenous T. harzianum strains were selected for copper tolerance, and three indigenous T. longibrachiatum strains were selected for nickel tolerance tests. Strains were isolated from the soils with the highest and among the lowest DTPA-extractable metal concentrations to determine whether the adaptation to different concentrations of metals affects the mechanisms of remediation. Mechanisms of metal removal were determined using Fourier-transform infrared spectroscopy (FTIR) and X-ray fluorescence spectroscopy (XRF), non-destructive methods characterized by high measurement speed with little or no need for sample preparation and very low costs. Increased DTPA-extractable metal content for nickel and copper was detected in the soil samples above the target value (TV), and for nickel above the soil remediation intervention values (SRIVs), for total metal concentrations which were previously determined. The SRIV is a threshold of metal concentrations indicating a serious soil contamination, thus confirming the need for soil remediation. The use of FTIR and XRF methods revealed that the presence of both biosorption and accumulation of metals in the Trichoderma cells, providing good bioremediation potential for Ni and Cu
Optimization of Caper Drying Using Response Surface Methodology and Artificial Neural Networks for Energy Efficiency Characteristics
No full textOne of the essential factors for the selection of the drying process is energy consumption. This study intended to optimize the drying treatment of capers using convection (CD), refractive window (RWD), and vacuum drying (VD) combined with ultrasonic pretreatment by a comparative approach among artificial neural networks (ANN) and response surface methodology (RSM) focusing on the specific energy consumption (SEC). For this purpose, the effects of drying temperature (50, 60, 70 degrees C), ultrasonication time (0, 20, 40 min), and drying method (RWD, CD, VD) on the SEC value (MJ/g) were tested using a face-centered central composite design (FCCD). RSM (R-2: 0.938) determined the optimum drying-temperature-ultrasonication-time values that minimize SEC as; 50 degrees C-35.5 min, 70 degrees C-40 min and 70 degrees C-24 min for RWD, CD and VD, respectively. The conduct of the ANN model is evidenced by the correlation coefficient for training (0.976), testing (0.971) and validation (0.972), which shows the high suitability of the model for optimising specific energy consumption (SEC)
Synthesis, characterization and electrochemical properties of iron doped phosphate tungsten heteropoly acid (Fe-PWA) and it’s bronze (Fe-PWB): Comparative study
No full textIn this work, synthesized 12-tungstenphosphoric acid (H3PW12O40 × nH2O; PWA) was further ionically exchanged with Fe3+ ions, which led to the formation of the 12-tungstophosporic acid iron salt, (FePW12O40 × nH2O; Fe-PWA). Fe-PWA was then subjected to thermal analysis (TGA/DTA), determining the phase transition temperature of 576 °C from Fe-PWA to its corresponding phosphate tungsten bronze doped with iron, Fe-PWB. Using the X-ray powder diffraction (XRPD), Fourier-transform infrared spectroscopy (FTIR), and Scanning electron microscopy with an energy dispersive X-ray spectroscopy (SEM-EDS) method, the obtained Fe-PWA and Fe-PWB were additionally characterized, and compared. Due to channels and cavities in their structures, Fe-PWA and Fe-PWB were next examined as electrode materials for aqueous rechargeable batteries. Electrochemical measurements were done in aqueous solutions of 6 M LiNO3 by cyclic voltammetry. Fe-PWA and Fe-PWB exhibit different redox processes, which are discussed thoroughly in this work. Electrochemical results are showing that within the Fe-PWA structure, more Li+ ions can be intercalated in the first discharge cycle, but consecutive cycling leads to a fast capacity fade. While the Fe-PWB redox process was stable during cycling, its specific capacity is limited by the material's poor electrical conductivity. Improvements in Fe-PWB conductivity must be addressed in future studies in order to boost material’s electrochemical performance.У овом раду синтетисана је 12-волфрам фосфорна киселина (H3PW12О40 × nH2О; PWA), која је даље јонски допирана са Fe3+ јонима, што је довело до формирања соли гвожђа 12-волфрам фосфорне киселине Fe-PWA соли (FePW12О40×nH2О). Fe-PWA је затим испитан помоћу термијске анализе (TGA/DTА), фазни прелаз Fe-PWA одиграва се на температури од 576 oC, формирајући фосфат волфрамову бронзу допирану гвожђем Fe-PWB. Применом метода дифракције рендгенских зрака на праху, инфрацрвене спектроскопије са Фуријеовом трансформацијом и скенирајуће електронске микроскопије уз енергетску дисперзивну рендгенску спектроскопију, добијени Fe-PWB је додатно карактерисан, чиме је потврђена жељена структура. Због канала и шупљина у њиховим структурама, Fe-PWA и Fe-PWB су затим испитани као електродни материјали за пуњиве батерије. Електрохемијска мерења вршена су у воденим растворима 6М LiNО3 цикличном волтаметријом. Електрохемијски резултати показују да унутар структуре Fe-PWA, више Li+ јона може бити интеркалирано у првом циклусу пражњења, али даље циклирање доводи до брзог смањења капацитета. Док је редокс процес Fe-PWB био стабилан током циклирања, његов специфични капацитет је ограничен слабом електричном проводљивошћу материјала. Специфични капацитет Fe-PWB је скоро незнатан, па је неопходно оптимизовати његове физичко-хемијске особине како би се вредност његовог специфичног капацитета повећала. Побољшање проводљивости Fe-PWB биће истраживана у будућим студијама, како би се побољшале електрохемијске перформансе материјала