scholarly journals Changes in the Physical Properties of Precipitation in Pine Stands in the Area with A Low Degree of Air Pollution (Western Pomerania)

2013 ◽  
Vol 32 (3) ◽  
pp. 27-37 ◽  
Author(s):  
Robert Kruszyk
Keyword(s):  
Air Pollution ◽  
Physicochemical Properties ◽  
Physical Properties ◽  
Dry Deposition ◽  
Bulk Precipitation ◽  
Total Load ◽  
Low Degree ◽  
Canopy Leaching ◽  
Pine Stands

Abstract The study presents the results of research conducted in the years 2010-2012 in pine stands in Western Pomerania. The research included physicochemical properties of bulk precipitation and throughfall. The results confirm that despite a decrease in the total throughfall in the interception process, the size of mineral and organic depositions in pine stands exceeded values recorded for bulk precipitation. It was caused both by the process of enriching the throughfall with (K+, Mg2+) rinsed out of needles and leaves and by washing off the dry deposition (NH4+, Cl-, Na+, SO42-, NO3 -). The share of leaching processes for K+ was 74.1%, while for Mg2+ 23.6% of the total load of these elements brought to the ground with throughfall. In the case of Ca2+ no canopy leaching was observed for this element. The throughfall acidification processes were mostly caused by NO3-.

scholarly journals Preliminary Studies Regarding the Physicochemical Characteristics of Some Balsamic Vinegars

1970 ◽  
Vol 66 (2) ◽  
Author(s):  
Delia Mihaela TRUTA ◽  
Maria TOFANA ◽  
Sonia Ancuţa SOCACI ◽  
Rowena CHELEMAN
Keyword(s):  
Physicochemical Properties ◽  
Physical Properties ◽  
Quality Evaluation ◽  
Physicochemical Characteristics ◽  
Production Method ◽  
Chemical Information ◽  
Grape Must ◽  
The Third ◽  
The Future ◽  
Balsamic Vinegar

The aim of this work is to analyze the chemical and physical properties of balsamic vinegar, in order to improve the chemical information about this product, useful for its authentication and quality evaluation. Using three balsamic vinegars purchased in local markets as samples, this study investigated the labeling and the physicochemical properties of commercial concentrated balsamic vinegar in order to understand their production method and quality. Two of the samples were balsamic vinegars from Modena (BVM) and the third was a balsamic vinegar from Kalamata (BVK). According to the labels, all the balsamic vinegars samples were made of grape must and had an acidity of 6%. The appearance of the samples of vinegar differed significantly, but the acidity from the label was the same for all. Since people are paying much more attention to health, the number of concentrated vinegar products is expected to increase in the future. Thus, appropriate rules and physicochemical properties are required to regulate vinegar production and quality.

scholarly journals Influences of Temperature on the Conversion of Ammonium Tungstate Pentahydrate to Tungsten Oxide Particles with Controllable Sizes, Crystallinities, and Physical Properties

2018 ◽  
Vol 16 (2) ◽  
pp. 124 ◽  
Author(s):  
Asep Bayu Dani Nandiyanto ◽  
Heli Siti Halimatul Munawaroh ◽  
Tedi Kurniawan ◽  
Ahmad Mudzakir
Keyword(s):  
Physicochemical Properties ◽  
Physical Properties ◽  
Undergraduate Students ◽  
Tungsten Trioxide ◽  
Model Material ◽  
Effect Of Temperature ◽  
Water Molecules ◽  
Ammonium Ions ◽  
Experimental Procedure ◽  
Ammonium Tungstate

The purpose of this study was to investigate influences of temperature on the conversion of ammonium tungstate pentahydrate (ATP) powder to tungsten trioxide (WO3) particles with controllable sizes, crystallinities, and physicochemical properties. In this study, we used a simple thermal decomposition method. In the experimental procedure, we explored the effect of temperature on the physicochemical properties of ATP by testing various heating temperatures (from 100 to 900 °C). The heated ATP samples were then characterized by a physical observation (i.e. color) and various analysis methods (i.e. a thermal gravimetric and differential thermal analysis, infrared spectroscopy, an X-ray diffraction, and a scanning electron microscope). Experimental results showed that increases in temperature had an impact to the decreases in particle size, the change in material crystallinity, and the change in physical properties (e.g. change of color from white, orange, to yellowish green). The relationships between the reaction temperatures and the physicochemical properties of the ATP were also investigated in detail along with the theoretical consideration and the proposal of the WO3 particle formation mechanism. In simplification, the phenomena can be described into three zones of temperatures. (1) Below 250 °C (release of water molecules and some ammonium ions).; (2) At 250-400 °C (release of water molecules and ammonium ions, restructurization of tungsten and oxygen elements, and formation of amorphous tungsten trioxide). (3) At higher than 400 °C (crystallization of tungsten trioxide). Since ATP possessed reactivity on temperature, its physicochemical properties changing could be observed easily, and the experimental procedure could be done easily. The present study will benefit not only for “chemistry and material science” but also potentially to be used as a model material for explaining the thermal behavior of material to undergraduate students (suitable used for a class and laboratory experiment and demonstration).

Dispiroacridine-indacenobisthiophenes positional isomers: Impact of the bridge on the physicochemical properties

2021 ◽  
Author(s):  
Jean-David Peltier ◽  
Benoît Heinrich ◽  
Bertrand Donnio ◽  
Olzhas A. Ibraikulov ◽  
Thomas Heiser ◽  
...  
Keyword(s):  
Phase Transitions ◽  
Physicochemical Properties ◽  
Physical Properties ◽  
Charge Transport ◽  
Energy Levels ◽  
Molecular Organization ◽  
Positional Isomers ◽  
Lumo Energy ◽  
Positional Isomerism ◽  
Homo Lumo

We report the influence of positional isomerism on the electronic (electrochemical HOMO/LUMO energy levels), photophysical and physical properties (molecular organization, crys¬¬tallinity and phase transitions) and charge transport properties of dispiroacridine-in¬da¬ce¬no¬bis¬thio¬phene...

scholarly journals Vegetation feedbacks during drought exacerbate ozone air pollution extremes in Europe

2020 ◽  
Author(s):  
Meiyun Lin ◽  
Larry Horowitz ◽  
Yuanyu Xie ◽  
Fabien Paulot ◽  
Sergey Malyshev ◽  
...  
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Drought Stress ◽  
Dry Deposition ◽  
Surface Ozone ◽  
Ozone Pollution ◽  
Ozone Uptake ◽  
Vegetation Feedbacks ◽  
Ozone Episodes ◽  
Pollution Episodes

<p>This study highlights a previously under-appreciated “climate penalty” feedback mechanism - namely, substantial reductions of ozone uptake by water stressed vegetation – as a missing piece to the puzzle of why European ozone pollution episodes have not decreased as expected in recent decades, despite marked reductions in regional emissions of ozone precursors due to regulatory changes. The most extreme ozone pollution episodes are linked to heatwaves and droughts, which are increasing in frequency and intensity over Europe, with severe impacts on natural and human systems. Under drought stress, plants close their stomata to reduce water loss, consequently limiting the ozone uptake by vegetation (a component of dry deposition), leading to increased surface ozone concentrations. Such land-biosphere feedbacks are often overlooked in prior air quality projections, owing to a lack of process-based model formulations. Here, we use six decades of observations and Earth system model simulations (1960-2018) with an interactive dry deposition scheme to show that declining ozone removal by water-stressed vegetation in the warming climate exacerbate ozone air pollution over Europe. Incorporated into a dynamic vegetation land – atmospheric chemistry – climate model, the dry deposition scheme mechanistically describes the response of ozone deposition to atmospheric CO<sub>2 </sub>concentration, canopy air vapor pressure deficit, and soil water availability. Our observational and modeling analyses reveal drought stress causing as much as 70% reductions in ozone removal by forests. Reduced ozone removal by water-stressed vegetation worsens peak ozone episodes during European mega-droughts, such as the 2003 event, offsetting much of the air quality improvements gained from regional emission controls. Accounting for vegetation feedbacks leads to a three-fold increase in high surface ozone events above 80 ppbv (8-hour average) and a 20% increase in the sensitivity of ozone pollution extremes (95<sup>th </sup>percentile) to increasing temperature. As the frequency of hot and dry summers is expected to increase in the coming decades, this ozone climate penalty could be severe and therefore needs to be considered when designing clean air policy in the European Union. </p><p>Notes: This study is currently under review for possible publication in Nature Climate Change. </p>

scholarly journals Measurement of Physicochemical Properties, Electrical and Thermal Conductivity of Wood Ash for Effective Soil Amendment

2021 ◽  
Vol 11 (2) ◽  
pp. 176
Author(s):  
M O Kanu ◽  
Gabriel Wirdzelii Joseph ◽  
Israel George
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Plant Growth ◽  
Physicochemical Properties ◽  
Physical Properties ◽  
Soil Amendment ◽  
Agricultural Soils ◽  
Wood Ash ◽  
Heat Energy ◽  
Total Dissolved Solid

The ability of the soil to regulate heat energy is important for plant growth, soil texture and strength. Many agricultural soils are acidic in nature which tends to limit plant growth and microbial activity. Aside from agricultural lime, wood ash is used to amend physical and physicochemical properties of the soil. To maintain the soil hydraulic and physicochemical properties and to increase plant yield, it is important to know the physicochemical and physical properties of the ash used. The physiochemical and physical properties vary across various plant species. Ash samples from seven different plants were used for this study. The Horiba metre was used to measure the electrical conductivity, pH, Total Dissolved Solid (TDS) and salinity of the samples, while the Lees Disc apparatus was used to measure the thermal conductivity of the samples. The study revealed that moringa olieferra ash has the highest salinity, TDS and Electrical conductivity, while azadichta indica and tiobroma cacoa have least pH. Also, Kyah seleelygalisis and azadichta indica had the highest and lowest thermal conductivity respectively.

scholarly journals Violaxanthin and diadinoxanthin de-epoxidation in various model lipid systems.

2012 ◽  
Vol 59 (1) ◽  
Author(s):  
Dariusz Latowski ◽  
Reimund Goss ◽  
Monika Bojko ◽  
Kazimierz Strzałka
Keyword(s):  
Physicochemical Properties ◽  
Physical Properties ◽  
Mathematical Description ◽  
Xanthophyll Cycle ◽  
Three Dimensional ◽  
Enzyme Activation ◽  
Special Focus ◽  
Hydrophobic Core ◽  
Hydrophobic Fraction ◽  
Lipid Micelles

The xanthophyll cycle is an important photoprotective process functioning in plants. One of its forms, the violaxanthin (Vx) cycle, involves interconversion between: Vx, antheraxanthin (Ax) and zeaxanthin (Zx). Another kind of the xanthophyll cycle is the diadinoxanthin (Ddx) cycle in which interconversion between Ddx and diatoxanthin (Dtx) occurs. In this study an information on molecular mechanism and regulation of these two types of the xanthophyll cycle is presented. The influence of lipids on the de-epoxidation of the xanthophyll cycle pigments was investigated, with special focus put on the significance of physical properties of the aggregates formed by inverted lipid micelles, which are necessary for activity of the xanthophyll cycle enzymes. In particular, thickness of the hydrophobic fraction of the aggregates, size of the inverted micelles, suggested by mathematical description of the structures and solubility of Vx and Ddx in various kind of lipids were studied. Obtained results show that the rate of de-epoxidation is strongly dependent on the physicochemical properties of the lipids used. The key role for enzyme activation play non-bilayer lipids and the parameters of inverted micelles such as thickness, fluidity of hydrophobic core and their diameter. The presented results show that MGDG and other non-lamellar lipids like different forms of phosphatidylethanolamine are necessary for the Vx and Ddx de-epoxidation because they provide the three-dimensional structures, which are needed for the binding of de-epoxidases and for the accessibility of Vx and Ddx to these enzymes.

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