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Managing municipal solid waste (MSW) presents many challenges, including the production of methane when MSW biodegrades in landfills. The search for methods to predict methane generation easily and...

Dye-sensitized solar cells (DSSCs) associated to the class of thin-film solar cells which have been under recent research work for more than two decades due to their low cost, simple preparation technology, low energy consumption, roll-to-roll manufacturing, eco-friendly, durable and light weight. Dye-sensitized solar cells (DSSCs) were fabricated using TiO2 as the photo anode and the composite of PANI and FeS2 as a counter electrode. The effect of the contents on the DSSC performance was investigated by adjusting the ratios of PANI and FeS2. It was found that the optimized DSSC efficiency of 0.9 % to 2.02% was achieved. The structure, surface morphology, elemental composition and functional groups of the PANI and FeS2 composites were characterized by XRD, SEM, TEM and FTIR analysis. This article provides an in-depth discussion on fabrication of DSSC based on polyaniline/FeS2 composite as counter electrode, operating conditions, prospective efficient materials and FTIR characteristics. From the obtained results, the composites of PANI and FeS2 counter electrode is served as an efficient, low-cost counter electrode (CE) material for dye-sensitized solar cells (DSSCs).

Between 1979 and 2003, a 35 cm thick layer of laminated tufa formed around a wooden pillar located at the beginning of the Korana River, which emerges from the Plitvice Lakes, Croatia. The laminated tufa structure allowed for the stratigraphic analysis of mineral, elemental and δ18O and δ13C isotope composition. Results are compared to other carbonate archives (lake sediments) from the Plitvice Lakes and to measured water physical–chemical data collected in the same time. An increase in water temperature and decrease in Mg/Ca ratio was observed during that period. Results showed that the tufa Mg/Ca ratio and δ18O could not be used as a temperature proxy, while an observed δ18O increase after 1990 was attributed to increase in evaporation rate. Furthermore, the constant increase in redox-sensitive elements (Mn) towards the external part of tufa may indicate periodic events of anoxia at the sediment/water interface. Local enrichment factors (LEFs) for potentially toxic elements were calculated using the background function and Al as the normalizing element. The LEFs showed an enrichment pattern of Cu and Pb in 1983 and 2001, which could indicate their anthropogenic origin and the sensitivity of the tufa to environmental changes.

A thermo-sensitive film composed of polycaprolactone and poly(N-isopropylacrylamide) was fabricated via electrospinning, with ketoconazole as the model drug. The morphology, elemental composition, ...

‏Shilajit is used commonly as Ayurvedic medicine worldwide which is Rasayana herbo-mineral substance and consumed to restore the energetic balance and to prevent diseases like cognitive disorders and Alzheimer. Locally, Shilajit is applied for patients diagnosed with bone fractures. For safety of the patients, the elemental analysis of Shilajit is imperative to evaluate its nutritional quality as well as contamination from heavy metals. The elemental composition of Shilajit was conducted using three advanced analytical techniques (LIBS, ICP, and EDX). For the comparative studies, the two Shilajit kinds mostly sold globally produced in India and Pakistan were collected. Our main focus is to highlight nutritional eminence and contamination of heavy metals to hinge on Shilajit therapeutic potential. In this work, laser-induced breakdown spectroscopy (LIBS) was applied for qualitative and quantitative analysis of the Shilajit. Our LIBS analysis revealed that Shilajit samples composed of several elements like Ca, S, K, Mg, Al, Na, Sr, Fe, P, Si, Mn, Ba, Zn, Ni, B, Cr, Co, Pb, Cu, As, Hg, Se, and Ti. Indian and Pakistani Shilajits were highly enriched with Ca, S, and K nutrients and contained Al, Sr, Mn, Ba, Zn, Ni, B, Cr, Pb, As, and Hg toxins in amounts that exceeded the standard permissible limit. Even though the content of most elements was comparable among both Shilajits, nutrients, and toxins, in general, were accentuated more in Indian Shilajit with the sole detection of Hg and Ti. The elemental quantification was done using self-developed calibration-free laser-induced breakdown spectroscopy (CF-LIBS) method, and LIBS results are in well agreement with the concentrations determined by standard ICP-OES/MS method. To verify our results by LIBS and ICP-OES/MS techniques, EDX spectroscopy was also conducted which confirmed the presence above mentioned elements. This work is highly significant for creating awareness among people suffering due to overdose of this product and save many human lives.

Radiocesium-bearing microparticles (CsMPs) from Fukushima Daiichi Nuclear Power Plant (FDNPP) are observed in Eastern Japan. To examine their source and formation, multiple particles were isolated from soils from three sites around the FDNPP and their radioactivity, morphology, and elemental composition were analyzed. Cesium-137 radioactivity ranged from 0.23 to 8.57 Bq and particles were primarily composed of Si, Fe, Zn, C, and Cs at each site. Uranium-rich parts in certain CsMPs show their origin in the vicinity of the nuclear reactor. Our results will help characterize CsMPs and evaluate the internal dose exposure of personnel employed at the FDNPP.

To replenish a specific consumable material, experimental samples of transport capsules were made, intended for neutron activation analysis for short-lived isotopes. The correspondence of the manufactured capsules to the real conditions of their transportation has been studied. The study of the elemental composition of the capsule material has been carried out. Analysis of the spectra of induced activity showed the presence of metal impurities in polyethylene, which must be taken into account when performing neutron activation analysis.

Lignocellulosic biomass is an important source of renewable energy and a potential replacement for fossil fuels. In this work, the X-ray fluorescence (XRF) method was used to analyze the elemental composition of raw and pretreated lignocellulosic biomass of cassava peels, corn cobs, rice husks, sugarcane bagasse, yam peels, and mixtures of cassava peels and yam peels, corn cobs and rice husks and all five biomass samples combined. The influence of particle size on elemental properties was investigated by screening the selected biomass into two size fractions, of an average of 300 and 435 µm, respectively. The total concentration of Mg, Al, Si, P, S, Cl, Ca, Ti, Cr, Mn, Fe, Co, Cu, Zn, Sn, Ni, Br, Mo, Ba, Hg, and Pb were determined for each of the biomass samples before and after the different pretreatments adopted in this study. From the results of the analysis, there was a significant reduction in the concentration of calcium in all the analyzed biomass after the alkaline pretreatment with rice husks biomass having the lowest concentration of 66 ppm after the alkaline pretreatment. The sulfur content of the acid pretreated biomass increased considerably which is likely due to the sulfuric acid used for the acid pretreatment. The fact that a mixture of biomass feedstock affects the properties of the biomass after pretreatment was validated in the mixed biomass of cassava peels and yam peels biomass as an example. The concentration of Mg in the mixed biomass was 1441 ppm but was 200 ppm and 353 ppm in individual cassava peels and yam peels respectively. The results of this study demonstrated that pretreated mixtures of biomass have varied elemental compositions, which could be an important factor affecting downstream processes, especially if a hybrid feedstock is used in a large-scale application.

In Siberia, when harvesting commercial coniferous wood and pine nuts, a large amount of waste remains in the form of needles and shells. These organic residues that require recycling may be of interest as raw materials for the production of feed additives in animal husbandry, so it is important to study their chemical composition. The study of the elemental composition of water extracts of pine nut shells and pine needles prepared under different conditions: whole and crushed shells – at an extraction temperature of 25 and 100 °С and duration of infusion 5 and 24 hours; pine needles – at an extraction temperature of 100 °С and duration of infusion 5 and 24 hours. The elemental composition was determined by inductively coupled plasma mass spectrometry. As a result of research, it was found that the most effective extraction of elements in the infusions of the studied raw materials was observed at a water temperature of 100 °С and duration of infusion 24 hours. At the same time, crushing the pine nut shell allowed to increase the degree of extraction of elements. It was found that extracts of pine nut shell from macronutrients contained the most K, Cl, Mg, P, from microelements – Zn, Mn and Fe; extracts of pine needles from macronutrients contained more K, Mg, Cl, from microelements – Mn, Zn and Fe. The highest absorption capacity was found in samples of crushed pine nut shells.

The precise characterization of the elemental composition of cereals and cereal products is becoming crucial to assess their nutritional values, geographical labeling, and also toxicological profile. Inductively coupled plasma-mass spectrometry (ICP-MS) has become popular for the elemental analysis of foods in recent years. Analytical performance of the inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) is improved with a reaction/collision cell that provides an interference-free analysis of most of the elements including phosphorus and sulfur. In this study, an analytical method was optimized for the quantification of 57 elements using ICP-MS/MS technique and validated for 25 elements that were available in certified reference materials (CRMs). Then, the mineral contents of semolina samples obtained from the durum wheat (Triticum durum) cultivars were analyzed according to the validation procedure. Recoveries of the elements were found in the range of 92-108% for the digested CRM. The method was robust for all elements and the results indicated good precision for the analytical method. The inter- and intra-day precision values were found below 5%, and in the range of 0.11-3.31% and 0.09-4.51%, respectively. Analyzed elements showed significant variability among the semolina samples. The variety and growing conditions might have influences on the elemental composition of semolina samples.

Between June and September 2018, particulate matter (PM) samples were taken in the Sartenejas Valley, southeast of Greater Caracas, Venezuela. The aim was to evaluate the morphology and the elemental chemical composition of particulate matter and establish possible emission sources during the rainy season. Functional groups were identified by FTIR spectroscopic analysis, and morphology and elemental composition were obtained by SEM–EDX analysis. The sampling period coincided with a Sahara dust storm. The SEM–EDX and FTIR analyses found evidence of mineral elements related to soil and crustal origins. The presence of C-rich or C-containing aerosols is related to biological sources or mineral carbon. SEM–EDX analysis of PM revealed the following particle groups: geogenic, metallic, C-rich, and secondary aerosols. Quantitative source appointments through principal component analysis (PCA) corroborated PM sources, including soil dust, sea salts, and reacted aerosols. According to the authors’ knowledge, this study represents the first report to indicate that an episode of African dust could influence the particles collected in an intertropical continental sector in Venezuela, South America.

When environmental conditions change, microalgae can modulate the size of their macromolecular pools and their elemental composition in order to accommodate their nutritional and energetic demands....

The seasonal changes in the elemental composition of surface aerosol in Moscow are considered in four data series: for summer and autumn 2019 and winter and spring 2020. The surface aerosol is significantly enriched with sulfur, heavy metals, and metalloids (Cu, Zn, Cd, Sb, Pb, Bi, etc.). The mass concentrations, mass percentages, and enrichment factors for different elements in aerosol particles are determined and compared for different seasons. The spatial distribution of elements in surface aerosol is not uniform through the city, which may be associated with the specificity of local sources, underlying surface, and wind regime in different regions of Moscow. The highest concentrations of a number of terrigenous and anthropogenic elements are revealed in the Central Administrative District of Moscow. The causes for seasonal variability in the elemental composition of surface aerosol in the Moscow megalopolis and possible sources of elements are discussed.

This study aimed to investigate the chemical profile, proximate and elemental composition of leaves and flowers of Ocimum basilicum grown in Sudan. Gas Chromatography-Mass Spectrometer (GC-MS) was used for the analysis of the n-hexane extracts. Results showed that fifty six compounds were detected from the aerial part of the plant. Most of the identified compounds were terpenoids. Monoterpenes represented 47.19%of the n-hexane extract while sesquiterpenes were 32.51%. The major compounds were linalool (18.16%), methyl eugenol (16.18%), α-terpineol (10.02%), and Eucalyptol (8.51%) respectively. Chemical proximate analysis was carried using standard analytical methods. Results showed that the plant was rich in moisture content, total ash, crude fiber and fiber protein. Elemental analysis was performed using the Atomic Absorption Spectrometer and flame emission for the detection of Ca, Fe, Na, K, Mg, Pb and Mn. Results demonstrated higher calcium and potassium contents. In conclusion O. basilicum grown in Sudan was a good source of food and therapeutic agents which could be of use in food and pharmaceutical industries.

Introduction: Terminalia catappa is a large tropical tree in the lead wood tree family, combretacea. This plant is regarded as a medicinal plant and can be used in the treatment of cough, syphilis, hydropsy, rheumatism, and other infections. Aim: This study assessed the nutritional value of Terminalia catappa and the composition of elements present in the plant fruit. Methods: Proximate analysis was carried out according to food chemistry analytical methods and elements were estimated by atomic absorption and flame spectroscopy respectively. Results: Proximate analysis showed that the fruits contained 81.96% moisture content, 1.47% ash, 0.04% crude fat, 1.11% crude protein, 14.05% carbohydrate, and 1.41% crude fibre. The fruits were found to be good sources of minerals. Sodium (2.1±0.01 mg/100 g), potassium (72.5±1.03 mg/100 g), calcium (320±2.00mg/100g), magnesium (20±2.65 mg/100 g), iron (20±3.0 mg/100 g), manganese (2±0.36 mg/100 g), and zinc (8±1.25 mg/100 g). Conclusion: The results revealed the presence of nutrients such as proteins, carbohydrates, crude fats, crude fibre, moisture, and ash in small amounts. And elements analysis shows that sodium, potassium, calcium, magnesium, iron, manganese, and zinc are in appreciable amount. These constituents are therefore responsible for the biochemical values of Terminalia catappa fruits.

For over 25 years, transmission electron microscopy (TEM) has provided a method for the study of aerosol particles with sizes from below the optical diffraction limit to several microns, resolving the particles as well as smaller features. The wide use of this technique to study aerosol particles has contributed important insights about environmental aerosol particle samples and model atmospheric systems. TEM produces an image that is a 2D projection of aerosol particles that have been impacted onto grids and, through associated techniques and spectroscopies, can contribute additional information such as the determination of elemental composition, crystal structure, and 3D particle structures. Soot, mineral dust, and organic/inorganic particles have all been analyzed using TEM and spectroscopic techniques. TEM, however, has limitations that are important to understand when interpreting data including the ability of the electron beam to damage and thereby change the structure and shape of particles, especially in the case of particles composed of organic compounds and salts. In this paper, we concentrate on the breadth of studies that have used TEM as the primary analysis technique. Another focus is on common issues with TEM and cryogenic-TEM. Insights for new users on best practices for fragile particles, that is, particles that are easily susceptible to damage from the electron beam, with this technique are discussed. Tips for readers on interpreting and evaluating the quality and accuracy of TEM data in the literature are also provided and explained.

In this paper, the contrasting properties of titanium dioxide nanoparticles in various compositions were considered. In the course of the work, methods for the synthesis of oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2 and SiO2-TiO2-ZrO2 were developed; the microstructure of oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2and SiO2-TiO2-ZrO2was studied; the stability of oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2and SiO2-TiO2-ZrO2 was determined. The elemental composition of the oxide materials SiO2-TiO2, SiO2-ZrO2, TiO2-ZrO2and SiO2-TiO2-ZrO2 has also been studied using SEM and XRD methods. It was found that SiO2-TiO2-ZrO2 nanocomposites with content of titanium dioxide from 8 to 9.5 % and zirconium dioxide from 0.5 to 2 % are completely insoluble in a highly alkaline medium. Thus, this composition is the most optimal for use as a contrast agent in optical coherence tomography.

This study is focused on the quantification of dust load on snow cover and chemical elements content in the solid phase of snow cover in the impacted areas of cement plants (the south of Western Siberia). Applying the instrumental neutron activation analysis, we identified chemical composition in the samples of the solid phase of snow cover. The results demonstrated that the dust load corresponded to the permissible pollution levels in the living zones. Dust pollution level varied from moderately hazardous to highly hazardous in the north-western impacted zone of the cement plants and raw material open pits. It was found that the predominant chemical element is Ca, as well as a group of rare-earth (Yb, Tb, Sm, La, Ce, etc.) elements in the solid phase of snow cover from the impacted zone of the cement plants.

Chemical constituents and elemental studies of seven Poaceae species were investigated using fourier-transformed infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS) and laser...

The present article introduces an elemental composition analysis of copper and bronze alloys from the burials of the Lepeshkinsky Stage of the Tagar culture, burial site Serebryakovo I in the Kiya-Chulym interfluve. The research featured mounds 2, 12, and 16, which date back to 3–1 centuries B.C. The metal composition of 72 items was investigated by inductively coupled plasma atomic emission spectroscopy (ICP AES). The obtained data were subjected to statistical processing, which revealed seven chemical-metallurgical and metallurgical groups of copper-based alloys. The bronze alloys did not depend on the typology of the tools, i.e. knives, engravings, mirrors, deer plaques, etc. The results confirmed the dating of the Lepeshkinsky site between the Saragashensky and the Tesinsky Stages of the Tagar culture. The items revealed a tendency towards a decrease in the proportion of tin bronzes and average concentrations of tin ligatures. The study proved that archaeometallurgical data can help to determine the relative-chronological position of the Tagar culture burial complexes.

The combined use of non-invasive on-site portable techniques, Raman microscopy, and X-ray fluorescence spectroscopy on seven imperial bowls and two decorated dishes, attributed to the reigns of the Kangxi, Yongzheng, Qianlong, and Daoguang emperors (Qing Dynasty), allows the identification of the coloring agents/opacifiers and composition types of the glazes and painted enamels. Particular attention is paid to the analysis of the elements used in the (blue) marks and those found in the blue, yellow, red, and honey/gilded backgrounds on which, or in reserve, a floral motif is principally drawn. The honey-colored background is made with gold nanoparticles associated with a lead- and arsenic-based flux. One of the red backgrounds is also based on gold nanoparticles, the second containing copper nanoparticles, both in lead-based silicate enamels like the blue and yellow backgrounds. Tin and arsenic are observed, but cassiterite (SnO2) is clearly observed in one of the painted decors (dish) and in A676 yellow, whereas lead (calcium/potassium) arsenate is identified in most of the enamels. Yellow color is achieved with Pb-Sn-Sb pyrochlore (Naples yellow) with various Sb contents, although green color is mainly based on lead-tin oxide mixed with blue enamel. The technical solutions appear very different from one object to another, which leads one to think that each bowl is really a unique object and not an item produced in small series. The visual examination of some marks shows that they were made in overglaze (A608, A616, A630, A672). It is obvious that different types of cobalt sources were used for the imprinting of the marks: cobalt rich in manganese for bowl A615 (Yongzheng reign), cobalt rich in arsenic for bowl A613 (but not the blue mark), cobalt with copper (A616), and cobalt rich in arsenic and copper (A672). Thus, we have a variety of cobalt sources/mixtures. The high purity of cobalt used for A677 bowl indicates a production after similar to 1830-1850., NA

Many studies report organic carbon stabilization by clay minerals, but the effects of land use and soil type on the properties of humic acids (HAs) are missing. The aim of the paper is to determine the effects of land use and soil types on the characteristics of HAs, which have a considerable influence on organic matter quality. It was hypothesised that the effect of the land use on HAs properties depends on the particular size distribution. The research was performed in three ecosystems: agricultural, forest, and meadow, located in Slovakia. From each of them, the samples of 4 soil types were taken: Chernozem, Luvisol, Planosol, and Cambisol. The soil samples were assayed for the content of total organic carbon (TOC) and the particle size distribution. HAs were extracted with the Schnitzer method and analysed for the elemental composition, spectrometric parameters in the UV-VIS range, and hydrophilic and hydrophobic properties, and the infrared spectra were produced. The research results have shown that the properties of HAs can be modified by the land use and the scope and that the direction of changes depends on the soil type. The HAs of Chernozem and Luvisol in the agri-ecosystem were identified with a higher “degree of maturity”, as reflected by atomic ratios (H/C, O/C, O/H), absorbance coefficients, and the FT-IR spectra, as compared with the HAs of the meadow and forest ecosystem. However, as for the HAs of Cambisol, a higher “degree of maturity” was demonstrated for the meadow ecosystem, as compared with the HAs of the agri- and forest ecosystem. The present research has clearly identified that the content of clay is the factor determining the HAs properties. Soils with a higher content of the clay fraction contain HAs with a higher “degree of maturity”.

In order to meet the increase in demand for food with the increase in population, the problem of environmental pollution arises as a result of agricultural practices carried out by moving away from scientific principles. Organic agriculture, on the other hand, is an agricultural method that aims to protect and sustain the health of soil-water-and biological diversity by prioritizing food security. This study was carried out in typic xerofluvent soil to determine the effect of matured farm manure applied in different doses on yield and elemental composition of leek plant. The total N content of the macro plant nutrients of the leek in different doses of animal manure applications differed depending on the application doses. In the first year N 1.62-2.52% and in the second year 1.15-2.17%, low N values were obtained in the control application and high N values in the H3 application in both years. Phosphorus nutrient was determined as 0.41-0.60% in the first year and 0.38-0.40% in the second year. The effect of different doses of animal manure on potassium was determined as 4.72-5.79% in the first year and 4.77-5.60% in the second year, the highest K was determined as H2 (5.79%) in the first year and H3 (5.60%) in the second year, higher than other applications values were obtained. The effect of the applications on Ca content was determined as 0.42-0.52% in the first year and 0.42-0.58% in the second year. It was determined as 0.42-0.52% Mg in the first year and 0.40-0.47% in the second year. Zinc content varying between 38.85-50.04 mg kg-1 in the first year and 39.79-51.39 mg kg-1 in the second year, copper element 4.20-5.04 mg kg-1 in the first year and 2.50-3.30 mg kg-1 in the second year. The Zn content varied according to the applications, and it was determined as 29.64-39.89 mg kg-1 in the first year and 27.07-33.24 mg kg-1 in the second year. According to the aplication, manganese was determined as 16.80-23.54 mg kg-1 in the first year and 19.19-22.10 mg kg-1 in the second year.

A metallurgical investigation was carried out on two early historic silver and copper punch marked coins. The objective was to study the metal composition, and the methods used in making of the early historic coins in India. The inductively coupled mass spectrometry was used to analyze the elemental composition of the coins. Metal formation and its mechanical properties were studied in physical metallurgical laboratory. The study revealed that the coins were not pure metal but an alloy. The silver coin contained copper as a major alloying element with other elements viz., V, Fe, Zn, Sn, Pb, As, Au in trace level while in copper the coin lead was the main alloying element with Ni, Fe, As, Au and Co in trace.

The acquisition of activated carbon on the market remains a major concern for developing countries due to its non-availability on a large scale. The objective of this work is to determine the physical and chemical characteristics of activated carbons produced from neem bark for use. The preparation of activated carbons was carried out using the chemical method with phosphoric acid (H3PO4) as the activating agent at different concentrations. In order to evaluate the performance of these activated carbons, various parameters have been determined. Thus, the BET method by nitrogen adsorption was used to determine the specific surface area. The t-plot and BJH methods provided knowledge of the pore volumes of the different carbons. The pore topography and the elemental composition were determined by the SEM–EDS method. The surface functions were determined using the Boehm method. The preparation resulted in the carbons CA 25, CA 30 and CA 60. The specific surface area values obtained ranged from 305.10 to 666.38 m2/g. Also, the results indicate a large number of pores on the surface of the carbons with volumes evolving with the increase in H3PO4 concentration. The results also indicate the acidic nature of the surface of each carbon. All these results show that the carbons produced from neem bark have very good characteristics for use in water treatment.

An inelastic neutron scattering system was developed to determine the elemental composition of large metallic materials. The geometrical size of the system was optimized by using Monte Carlo simulation. An experimental setup consisted of a DT neutron generator and a HPGe detector was built based on the optimized configuration and applied to analyze titanium samples. The net peak areas of titanium versus sample mass showed a linear dependence and the mass detection limit was 64 g. The prompt gamma spectra were compared to simulation data. The results demonstrated a good agreement for the signal-to-background ratio of titanium peak between measurements and simulations.

In the present study, green synthesis of silver nanoparticles (AgNPs) was performed using flower extracts of Aerva lanata (Al) from Amaranthaceae family. The size, shape, and elemental composition ...

The ability of carbon black samples of grades N115, N339, and OMCARB S820 to adsorb Alizarin Red S was studied. The physicochemical properties (textural characteristics, elemental composition, qualitative composition of oxygen-containing groups) of the initial carbon black samples were studied. The adsorption isotherms of Alizarin Red S on carbon black samples in the examined concentration range at рН 2 are described by the Henry equation; the Henry constants were calculated. The use of Alizarin Red S as a carbon black modifier allows the content of oxygen-containing groups on its surface to be increased. This approach can be used for developing new pigments based on carbon black.

Despite the wide use of urea and ammonium as N-fertilizers, no information is available about the proper ratio useful to maximize the efficiency of their acquisition by crops. Ionomic analyses of maize seedlings fed with five different mixes of urea and ammonium indicated that after 7 days of treatment, the elemental composition of plant tissues was more influenced by ammonium in the nutrient solution than by urea. Within 24 h, similar high affinity influx rates of ammonium were measured in ammonium-treated seedlings, independently from the amount of the cation present in the nutrient solution (from 0.5 to 2.0 mM N), and it was confirmed by the similar accumulation of 15N derived from ammonium source. After 7 days, some changes in ammonium acquisition occurred among treatments, with the highest ammonium uptake efficiency when the urea-to-ammonium ratio was 3:1. Gene expression analyses of enzymes and transporters involved in N nutrition highlight a preferential induction of the cytosolic N-assimilatory pathway (via GS, ASNS) when both urea and ammonium were supplied in conjunction, this response might explain the higher N-acquisition efficiency when both sources are applied. In conclusion, this study provides new insights on plant responses to mixes of N sources that maximize the N-uptake efficiency by crops and thus could allow to adapt agronomic practices in order to limit the economic and environmental impact of N-fertilization.

Trace elemental composition, sex hormones and antioxidant capacity of young women with menstrual irregularities were assessed in this study using standard methods. Forty (40) young female subjects with regular menstrual cycle and 40 young female subjects with different kinds of menstrual irregularities, a total of 80 volunteer subjects were used for the study. The subjects were sourced from the duo of Imo State University and Federal Medical Centre, both in Owerri, Nigeria. Each volunteer subject signed an informed consent form after the procedure and implications of the study were explained using a language the subject would understand. Trace elements such as zinc, copper, iron, and selenium; and antioxidant capacity assessed were insignificantly (p>0.05) affected in test subjects when compared to control subjects. Estrogen and sex hormone-binding globulin (SHBG) levels were significantly (p

The structure of aluminum-containing moieties in and within zeolite H-ZSM-5 catalysts is a complex function of the elemental composition of the catalyst, synthesis conditions, exposure to moisture,...