chemical analyses
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Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 239
Author(s):  
Jerzy M. Kupiec ◽  
Agnieszka Bednarek ◽  
Sebastian Szklarek ◽  
Joanna Mankiewicz-Boczek ◽  
Liliana Serwecińska ◽  
...  

The aim of this study was to assess the efficiency of the innovative SED-BIO system in limiting the inflow of pollutants to Jelonek Lake. The analyses were conducted in the Gniezno Lake District in Greater Poland (the western part of Poland). Physical and chemical analyses were conducted in the years 2016–2019. The results demonstrate that the system is highly effective in the reduction of such nutrients as nitrogen (NO3−—63%; NH4+—14.9%) and phosphorus (PO43−—19.3%). Although the presence of cyanobacteria was confirmed practically throughout the whole monitoring period of the system (2016), the specimens found in most samples were not toxigenic genotypes with a potential to produce microcystins. Microcystins (3 µg·L−1) were detected only once, immediately after the SED-BIO system had been installed in the river and pond, which demonstrates that this natural toxin was eliminated from the additional pool of contaminants that might be transported to Jelonek Lake.


Horticulturae ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 52
Author(s):  
Quynh Phan ◽  
Aubrey DuBois ◽  
James Osborne ◽  
Elizabeth Tomasino

Lipids have important impacts on wine sensory. By targeting the lipid sources in wine, mainly from grape tissues and yeast cell walls, it was possible to alter the wine lipid profile thus potentially changing the final product quality. This research examined the changes of wine total lipids, lipid composition and sensory characteristics of Pinot noir wines in response to the winemaking factors, fermentation temperature and yeast product addition. Pinot noir grapes were fermented at 16 °C and 27 °C. After fermentation, Oenolees® yeast product was added to the wines at three levels (0 g/L, 0.5 g/L and 1.0 g/L). The six wine treatments were subjected to chemical analyses measuring total lipids and an untargeted lipidomic approach analyzing lipid composition. High temperature fermentation wines had significantly higher total lipid content. Random forest analysis distinguished the wine groups based on the 25 main lipids, including free fatty acids, acylcarnitines, diglycerides, triglycerides and phospholipids. Taste and mouthfeel characteristics of each treatment were assessed using descriptive analysis and check-all-that-apply (CATA) techniques. Multivariate analyses showed that changing fermentation temperature significantly impacted sweetness and drying perception in Pinot noir wines. Yeast product addition had nuanced effects on wine lipid profiles and sensory perception.


Author(s):  
José Francisco Bergua ◽  
Ruslán Álvarez-Diduk ◽  
Andrea Idili ◽  
Claudio Parolo ◽  
Marc Maymó ◽  
...  

2022 ◽  
Vol 334 ◽  
pp. 08010
Author(s):  
Andrea Franzetti ◽  
Anna Espinoza ◽  
Enrico Barontini ◽  
Matteo Tucci ◽  
Paolo Bonelli ◽  
...  

Planar MFC prototypes were constructed and experimented to operate as sensors of the anoxic condition in a denitrification tank of a wastewater treatment plant in Italy, during different times in 2018 – 2019. Electrodes were differently enriched with carbon paint containing nanotubes and CeO2 nanoparticles. Performances of different electrodes were compared. Results underline critical anoxic conditions in the tank, that caused a very low signal and phenomena of signal reversion during some period of the year. the activity of aerobic microorganisms and protozoa growing and grazing the bacteria on the electrodes strongly influenced the signal of the MFCs. The presence of nanoceria enhanced, for some extent, the MFC signal, both in presence of reversing trends and in absence of these phenomena. In absence of reversing trends, nanoceria enhanced the MFC voltage. Such signal trends from MFCs can give, in real-time, useful information to optimize the purification process without the necessity of frequent biological and chemical analyses.


2021 ◽  
Vol 52 (6) ◽  
pp. 1498-1507
Author(s):  
M. A. Fayyadh ◽  
H. K. Ismail

The study area was located in the North of Iraq. Five sites were selected that have formed from the limestone parent material. One pedon dug in each site and was divided into a number of horizons. Thirty-five soil samples were collected for physical and chemical analyses. The climate of study sites were similar to the Mediterranean Sea climate which is hot dry in summer and cool humid in winter. The mean of annual precipitation, varies from one site to another. Studied soils classified as Mollisols, Inceptisols, Vertisols, and Aridisols. Study soils were relatively high clay content and its content at the surface horizons is lower than it at subsurface horizons, and soil texture was ranged between clayey to loamy, the high value for clay content indicates to soil development. Fine clay/Coarse clay ratio showed that the pathway of fine clay similar to the pathway of total clay. CEC values increased with increasing clay. Organic matter was high in the surface horizons and decrease with depth. The following pedogenic processes occurred in study soils loss, gain, leaching, illuviation, eluviation, alkalization, humification, lessivage, desalinization, calcification, decomposition, and synthesis.


2021 ◽  
Vol 22 (24) ◽  
pp. 13665
Author(s):  
Abbas Amini ◽  
Azadeh Fallah ◽  
Ahmad Sedaghat ◽  
Ahmad Gholami ◽  
Chun Cheng ◽  
...  

Natural phosphate (NP) and synthetic fluorapatite phosphate (SFAP) were proposed as stable, inexpensive, readily available and recyclable catalysts for the condensation of 1,2-diamines with 1,2-dicarbonyls in methanol to afford quinoxaline at room temperature. NP provided as high as 92–99% yield for quinoxalines in short reaction times (i.e., 1–45 min), while SFAP created quinoxalines with 87–97% yield in 60–120 min. From the chemical analyses, X-ray fluoresecency, X-ray diffraction, energy dispersive X-ray and Fourier-transform infrared spectroscopy methods, two main phases (CaO, P2O5) appeared in NP together with other low content phases (SiO2, Fe2O3). Compared to other phases, apatite (CaO and P2O5 as Ca10(PO4)6) played a major role in the catalytic activity of NP. SFAP with similar Ca/P atomic ratio showed a relatively lower catalytic activity than NP for the condensation of 1,2-diamine with 1,2-dicarbonyl in methanol at ambient temperature. To investigate the recyclability of catalysts, the surface properties of NP and 6-recycled NP were investigated using scanning electron microscopy, energy dispersive X-ray and Brunauer–Emmett–Teller and Barrett–Joyner–Halenda methods. Some differences were observed in NP and 6-recycled NP’s particle size, surface area, the volume and size of pores, and the content of elements; nevertheless, the use–reuse process did not noticeably change the catalytic property of NP.


2021 ◽  
Author(s):  
Степан Иванюков ◽  
Наталья Саранчина ◽  
Евгений Саранчин

Изучение существ – создателей важнейшего компонента жизни на планете – почвы, скорее всего, важная часть подготовки межпланетных космических команд. Работа представляет собой многоплановое исследование, где главным объектом выступает насекомое – Палочник аннамский. Автором проведены наблюдения за пищевой активностью и получены данные о количестве помета, то есть скорости формирования будущего гумуса. Проведено выращивание комнатного растения хлорофитум и оценено влияние смеси песка и гуано палочника на рост листьев и корней. Автору удалось провести серию химических анализов на количество нитратов в полученной «почве». Оценка концентрации нитратов в грунте проводилась как с помощью реагентов, так и с использованием прибора «Соэкс Эковизор F4». С их помощью получены данные о разных по времени формирования «почвах». The study of the creatures - creators of the most important component of life on the planet - the soil, first of all, is an important part of the preparation of interplanetary space teams. The work is a multifaceted study, where the main object is the insect – the Annam stick insect. The author carried out observations of food activity and obtained data on the amount of litter, that is, the rate of formation of future humus. A chlorophytum houseplant was grown and the effect of a mixture of sand and stick insect guano on the growth of leaves and roots was evaluated. The author managed to conduct a series of chemical analyses for the amount of nitrates in the resulting "soil". The assessment of the nitrate concentration in the soil was carried out both with the help of reagents and with the use of the device "Soex Ecovisor F4". With their help, data on "soils" of different formation times were obtained.


2021 ◽  
Vol 288 (1965) ◽  
Author(s):  
Michelina Pusceddu ◽  
Desiderato Annoscia ◽  
Ignazio Floris ◽  
Davide Frizzera ◽  
Virginia Zanni ◽  
...  

Honeybees use propolis collected from plants for coating the inner walls of their nest. This substance is also used as a natural antibiotic against microbial pathogens, similarly to many other animals exploiting natural products for self-medication. We carried out chemical analyses and laboratory bioassays to test if honeybees use propolis for social medication against their major ectoparasite: Varroa destructor . We found that propolis is applied to brood cells where it can affect the reproducing parasites, with a positive effect on honeybees and a potential impact on Varroa population. We conclude that propolis can be regarded as a natural pesticide used by the honeybee to limit a dangerous parasite. These findings significantly enlarge our understanding of behavioural immunity in animals and may have important implications for the management of the most important threat to honeybees worldwide.


2021 ◽  
Vol 1 ◽  
Author(s):  
Lucia Lazarowski ◽  
Alison Simon ◽  
Sarah Krichbaum ◽  
Craig Angle ◽  
Melissa Singletary ◽  
...  

Effective explosives detection requires dogs to generalize their response to untrained variations of targets that are related to those with which they were trained. Previous research suggests that dogs tend to be highly specific to their trained odors, and are sensitive to alterations in odor profiles. Triacetone triperoxide (TATP) is an increasingly popular homemade explosive due to the widespread accessibility of starting materials. The large variety of reagent sources and production approaches yields high variability in deployed formulations. Whether dogs trained with pure forms of TATP generalize to other variations is unknown, representing a potentially significant security gap. In the current study, we tested dogs (n = 11) previously trained to detect pure TATP with four variants: diacetone diperoxide (DADP), a homologue often created as a TATP byproduct, and three different clandestine TATP formulations designed to emulate those used by terrorists or insurgents. On average, dogs detected each untrained variant at rates equivalent to the trained TATP (ps > 0.07), with individual variability in first-trial alerts for some of the variants. Chemical analyses paralleled the canine results, showing distinct similarities and differences. For the TATP samples, the laboratory-grade was the purest sample tested and did not contain DADP or the TATP homologue that the three clandestine versions showed in their respective headspace profiles. The headspace results showed that each sample could be clearly identified as TATP, yet they showed recognizable differences due to their individual syntheses. These findings suggest that training on pure TATP may be effective for generalization to untrained variants. Further research is necessary to identify factors that influence individual variation in generalization between dogs, as well as other explosives.


2021 ◽  
Vol 14 (1) ◽  
pp. 22
Author(s):  
I. M. Camacho ◽  
A. T. Hoshino ◽  
B. A. Guide ◽  
R. M. M. Soares ◽  
L. M. de Oliveira ◽  
...  

Acknowledging the bio indicator importance of springtails (Hexapoda: Collembola) for soil quality, this study aimed to determine the abundance of these arthropods in different systems of rotation/succession with commercial and cover crops, while also verifying the agricultural factor associated to these arthropods’ population. In the Instituto de Desenvolvimento Rural do Paraná (IAPAR-EMATER), during six years, areas with differing crops in rotation/succession adopting the no-tillage system were studied. For each system, chemical analyses of the soil were conducted and the number of captured springtails in pitfall traps was counted. The phytosanitary products applied during the evaluations and the quantity of vegetal cover remaining after harvest were considered as well. No difference was found between the rotation/succession systems in relation to chemical soil attributes, however the largest number of springtails was found in crop covers from corn, Brachiaria sp., and canola. These crop covers, including wheat, resulted in the highest straw dry mass. When removing the system in which the predecessor crop had the highest quantities of fungicide application, a positive correlation (r = 0.63; p < 0.01) was found, between springtail abundance and highest amount of straw after the harvest. If no fungicide applications occur, the crops with the largest amount of vegetal cover favor springtail populations.


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