Chemical Denudation in a Geoecosystem in Acid Immision Conditions / Denudacja Chemiczna W Geoekosystemie W Warunkach Kwaśnej Imisji

Abstract There is an analysis of the physico-chemical properties and the chemical composition of precipitation in a forest geoecosystem in acid immision conditions. The data used in the analysis was collected between 2000 and 2010. In that period, a drop in the immision scale of S-SO2 in the atmospheric air had been observed, which consequently was one of the reasons for a drop in the precipitation acidity. The conclusion was that rainwater, after penetrating treetops and trunks, undergoes a significant transformation whose intensity depends on species composition of the forest stand. Statistically relevant differences were found in coniferous stands, in which a substantial drop in pH was noted, in addition to an increase in the load of components accumulated in the soil in relation to atmospheric precipitation. The calculated indicators of the eco-chemical state of waters (Ma%) have revealed that throughfall waters in coniferous stands and fir and beech stemflow contain significant amounts of aluminium, manganese, iron and hydrogen ions in the sum of cations. Also the indicator of acid-neutralizing capacity (ANCaq) shows that these waters are more enriched with sulfate, nitrate and chloride ions than bulk precipitation. The recorded variation eventuates from processes related to dry and humid deposition, as well as ion-exchange processes occurring within the stand. The obtained results point to an intensification of chemical denudation within the trunks, triggering disadvantageous changes in both biotic and abiotic part of the ecosystem. The effects of the increased inflow of souring agents to the soil through stemflow are significant acidification of the top mineral soil horizon and an increase in the hydrolytic acidity.

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Decomposition of hydrogen peroxide on nickel-silver two-component catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19842222 ◽

1984 ◽

Vol 49 (10) ◽

pp. 2222-2230 ◽

Cited By ~ 3

Author(s):

Viliam Múčka ◽

Rostislav Silber

Keyword(s):

Hydrogen Peroxide ◽

Chemical Properties ◽

Silver Ions ◽

Surface Concentration ◽

Chloride Ions ◽

Nickel Silver ◽

Silver Catalysts ◽

Physico Chemical ◽

Low Degree ◽

Defective Crystal

The catalytic and physico-chemical properties of low-temperature nickel-silver catalysts with nickel oxide concentrations up to 43.8% (m/m) are examined via decomposition of hydrogen peroxide in aqueous solution. The mixed catalysts prepared at 250°C are composed of partly decomposed silver carbonate or oxide and nickel carbonate or hydroxide decomposed to a low degree only and exhibiting a very defective crystal structure. The activity of these catalysts is determined by the surface concentration of silver ions, which is affected by the nickel component present. The latter also contributes to the thermal stability of the catalytic centres of the silver component, viz. the Ag+ ions. The concentration of these ions varies with the temperature of the catalyst treatment, the activity varies qualitatively in the same manner, and the system approaches the Ag-NiO composition. The catalytic centres are very susceptible to poisoning by chloride ions. A previous exposition of the catalyst to a gamma dose of 10 kGy from a 60Co source has no measurable effect on the physico-chemical properties of the system.

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The Influence of Wildfire on Aqueous-Extractable Soil Solutes in Forested and Wet Meadow Ecosystems Along the Eastern Front of the Sierra-Nevada Range, California

International Journal of Wildland Fire ◽

10.1071/wf9980079 ◽

1998 ◽

Vol 8 (2) ◽

pp. 79 ◽

Cited By ~ 30

Author(s):

RR Blank ◽

DC Zamudio

Keyword(s):

Sierra Nevada ◽

High Performance ◽

Mineral Soil ◽

Chemical Properties ◽

Exchange Chromatography ◽

Soil Horizon ◽

Significant Treatment ◽

Wet Meadow ◽

Soil Extracts ◽

Eastern Front

Information is lacking regarding the influence of pre-fire microsite conditions on post-wildfire soil chemical properties. Following a 1994 wildfire along the eastern front of the Sierra Nevada range, California, high performance ion exchange chromatography was used to quantify anions and cations in aqueous soil extracts by plant microsite (Pinus jeffreyi subcanopy, Calocedrus decurrens subcanopy, Carer microptera meadow, Salix scouleriana subcanopy), by depth (ash or litter, mineral soil horizon 0-5 cm), and by treatment (unburned, burned). As compared to the unburned treatment, post-wildfire ash and surface mineral horizons had significantly (P less than or equal to 0.05) higher concentrations of sodium, magnesium, formate, and chloride. Plant microsite interacted significantly with treatment for ammonium; all plant microsites had significantly higher ammonium in burned treatments and burned S. scouleriana and C. microptera microsites had significantly more ammonium than the C. decurrens or P. jeffreyi microsites. For pH and acetate there was a significant treatment × depth interaction in which concentrations were highest in burned ash layers. For sulfate, ortho-phosphate, and calcium, there was a significant plant microsite × treatment × depth interaction. In general, post-wildfire ash and soil mineral layers had significantly more sulfate and calcium than the unburned controls; ash layers contained significantly less ortho-phosphate than unburned litter layers. There was a significant treatment × depth interaction for magnesium, chloride, formate, acetate, potassium, and nitrate. Initial post-wildfire levels of short-chained aliphatic carboxylic acids were very high, especially in ash layers, and did not decline to preburn values by the following summer.

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Effect of exchanged MgAl-Hydrotalcite with carbonate on increases of acid neutralizing capacity: A good candidate as antacid

Current Nanomaterials ◽

10.2174/2405461506666210526145531 ◽

2021 ◽

Vol 06 ◽

Author(s):

Mustapha Dib ◽

Mohammed Naciri Bennani ◽

Ouchetto Hajiba ◽

Khadija Ouchetto ◽

Hafid Abderrafia ◽

...

Keyword(s):

Ir Spectroscopy ◽

Acid Neutralizing Capacity ◽

Precipitation Method ◽

Dose Titration ◽

Physico Chemical ◽

Neutralizing Capacity ◽

Ft Ir ◽

Chemical Techniques ◽

Co Precipitation ◽

Ft Ir Spectroscopy

Background: In this study, we determined the acid neutralizing capacity (ANC) of Mg/Al-Hydrotalcite-like compounds. The MgAl-hydrotalcites were synthesized by co-precipitation method at room temperature using Mg/Al molar ratios 2 and 3. The synthesized bioactive nanomaterials were characterized by various physico-chemical techniques such as TG/dTG, DRX, FT-IR spectroscopy, BET/BHJ and MEB/EDX. The antacid activity assay was done by converting both synthesized samples into liquids, 1 g of which was added to 50 ml of deionized water at 37°C under vigorous agitation. The acid neutralizing capacity (ANC) was evaluated with 0.1N HCl. The pH was constantly measured using a pH meter and values were recorded every minute up to 35 min. In order to improve the neutralizing power of the samples, we performed on the MgAl-HT3 synthesized an exchange of chlorides by carbonates. The exchanged Mg/Al-Hydrotalcite (MgAl-HTE) shows a high acid neutralization capacity (up to 13.5 mEq/g). Objective: To synthesize an MgAl-hydrotalcite-like compounds and evaluation of their acid neutralizing capacity and thus can be good candidates for pharmaceutical applications as antacid drugs. Methods: Preparation of MgAl-hydrotalcite-like compounds by coprecipitation methods - Characterization of samples by physico-chemical techniques such as TG/dTG, DRX, FT-IR spectroscopy, BET/BHJ and MEB/EDX. - Evaluation of acid neutralizing capacity by titration procedure (Dose-titration) . Results: This protocol describes the preparation of MgAlhydrotalcite-like using the classical coprecipitation method. The synthesized samples were characterized by various physicochemical techniques such as TG/dTG, DRX, FT-IR spectroscopy, BET/BHJ and MEB/EDX. The as-synthetized samples were used for the evaluation of their acid-neutralizing capacity (ANC). Further, an exchanged MgAl-Hydrotalcite with carbonate was described for the purpose to increases the acid-neutralizing capacity. Conclusion: In summary, this study describes a simple synthesis of MgAl-Hydrotalcites compounds by a co-precipitation method at constant pH around 10, with a ratio Mg/Al = 3 and 2 (referred to as MgAl-HT3 and MgAl-HT2). An exchange of the chlorides (not eliminated by washing) by the carbonates was carried out on hydrotalcite with a ratio Mg/Al = 3 and the solid obtained was named MgAl-HT3E. The materials MgAl-HT2, MgAl-HT3 and MgAl-TH3E were used to evaluate their antacid activity. To this end, a study was conducted to determine the acid neutralizing capacity (ANC). As a result, the MgAl-HT3E was able to increase acid neutralizing capacity and maintaining an ideal pH. These results could be interesting to prepare novel antacid drugs (due to the low cost of synthesized materials) essentially the hydrotalcite of Mg/Al ratio equal to 3 because of its relatively slow kinetics of releasing basic species and therefore of its beneficial action as an antacid.

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Selected Chemical Properties of Necrosols from the Abandoned Cemeteries Słabowo and Szymonka (Great Mazurian Lakes District)

Bulletin of Geography Physical Geography Series ◽

10.2478/v10250-012-0003-8 ◽

2012 ◽

Vol 5 (1) ◽

pp. 43-55 ◽

Cited By ~ 5

Author(s):

Leszek Majgier ◽

Oimahmad Rahmonov

Keyword(s):

Chemical Properties ◽

Soil Horizon ◽

Morphological Description ◽

Soil Profiles ◽

Anthropogenic Soils ◽

Physico Chemical ◽

Physical And Chemical ◽

Burial Grounds ◽

Cemetery Soils ◽

And Chemical Properties

Abstract The paper shows the occurrences of cemetery soils and the physico-chemical features of soils in the cemeteries Słabowo and Szymonka (Great Mazurian Lakes District). Necrosols are anthropogenic soils and belong to Urbanosols. They form only in the area of cemeteries. Four soil profiles (Necrosols) were investigated in terms of morphological description and chemical properties especially phosphorus (Pt), organic carbon (OC) and nitrogen (Nt). These profiles were compared with the reference profile (Rusty soil, according to WRB 2007 Brunic Arenosol) made outside the cemetery. On the basis of research Necrosol has been defined as a soil formed by special human activity in cemeteries and burial grounds with specific soil horizon sequence, and also physical and chemical properties.

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Decoration of specific sites on freeze-fractured membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081565 ◽

1978 ◽

Vol 36 (2) ◽

pp. 140-141

Author(s):

H. Gross ◽

H. Moor

Keyword(s):

Pure Water ◽

Freeze Fracture ◽

Chemical Properties ◽

Surface Forces ◽

Sulfate Pentahydrate ◽

Copper Sulfate Pentahydrate ◽

Physico Chemical ◽

Water Of Hydration ◽

Small Container ◽

Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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PHYSICO CHEMICAL PROPERTIES OF NICKEL OXIDE AT HIGH TEMPERATURE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1976798 ◽

1976 ◽

Vol 37 (C7) ◽

pp. C7-438-C7-442 ◽

Cited By ~ 2

Author(s):

R. FARHI ◽

G. PETOT-ERVAS

Keyword(s):

High Temperature ◽

Nickel Oxide ◽

Chemical Properties ◽

Physico Chemical

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Physico-Chemical Properties of Recombinant Desulphatohirudin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645073 ◽

1990 ◽

Vol 63 (03) ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

A Electricwala ◽

L Irons ◽

R Wait ◽

R J G Carr ◽

R J Ling ◽

...

Keyword(s):

Molecular Weight ◽

Gel Filtration ◽

Chemical Properties ◽

Alpha Helix ◽

Apparent Molecular Weight ◽

Correlation Spectroscopy ◽

Nmr Studies ◽

Recombinant Hirudin ◽

Physico Chemical ◽

Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

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KARAKTERISTIK TANAH DAN PERBANDINGAN PRODUKSI KELAPA SAWIT (Elaeis guineensis Jacq.) DENGAN METODE TANAM LUBANG BESAR DAN PARIT DRAINASE 2:1 PADA LAHAN SPODOSOL DI KABUPATEN BARITO TIMUR PROPINSI KALIMANTAN TENGAH - INDONESIA

Jurnal Pertanian Tropik ◽

10.32734/jpt.v2i2.2897 ◽

2015 ◽

Vol 2 (2) ◽

pp. 148-158

Author(s):

Surianto

Keyword(s):

Soil Texture ◽

Oil Palm ◽

Soil Profile ◽

Chemical Properties ◽

Exchangeable Cations ◽

Soil Horizon ◽

Soil Profiles ◽

Negative Effect ◽

Hole Profile ◽

And Chemical Properties

Spodosol soil of Typic Placorthod sub-group of East Barito District is one of the problem soils with the presence of hardpan layer, low fertility, low water holding capacity, acid reaction and it is not suitable for oil palm cultivation without any properly specific management of land preparation and implemented best agronomic practices. A study was carried out to evaluate the soil characteristic of a big hole (A profile) and no big hole (B profile) system and comparative oil palm productivity among two planting systems. This study was conducted in Spodosol soil at oil palm plantation (coordinate X = 0281843 and Y = 9764116), East Barito District, Central Kalimantan Province on February 2014, by surveying of placic and ortstein depth and observing soil texture and chemical properties of 2 (two) oil palm's soil profiles that have been planted in five years. Big hole system of commercial oil palm field planting on the Spodosol soil area was designed for the specific purpose of minimizing the potential of a negative effect of shallow effective planting depth for oil palms growing due to the hardpan layer (placic and ortstein) presence as deep as 0.25 - 0.50 m. The big hole system is a planting hole type which was vertical-sided with 2.00 m x 1.50 m on top and bottom side and 3.00 m depth meanwhile the 2:1 drain was vertical-sided also with 1.50 m depth and 300 m length. Oil palm production was recorded from the year 2012 up to 2014. Results indicated that the fractions both big hole profile (A profile) and no big hole profile (B profile) were dominated by sands ranged from 60% to 92% and the highest sands content of non-big hole soil profile were found in A and E horizons (92%). Better distribution of sand and clay fractions content in between layers of big hole soil profiles of A profile sample is more uniform compared to the B profile sample. The mechanical holing and material mixing of soil materials of A soil profile among the upper and lower horizons i.e. A, E, B and C horizons before planting that resulted a better distribution of both soil texture (sands and clay) and chemical properties such as acidity value (pH), C-organic, N, C/N ratio, CEC, P-available and Exchangeable Bases. Investigation showed that exchangeable cations (Ca, Mg, K), were very low in soil layers (A profile) and horizons (B profile) investigated. The low exchangeable cations due to highly leached of bases to the lower layers and horizons. Besides, the palm which was planted on the big hole system showed good adaptation and response positively by growing well of tertiary and quaternary roots that the roots were penetrable into deeper rooting zone as much as >1.00 m depth. The roots can grow well and penetrate much deeper in A profile compared to the undisturbed hardpan layer (B profile). The FFB (fresh fruit bunches) production of the non-big hole block was higher than the big hole block for the first three years of production. This might be due to the high variation of monthly rainfall in-between years of observation from 2009 to 2014. Therefore, the hardness of placic and ortstein as unpenetrable agents by roots and water to prevent water loss and retain the water in the rhizosphere especially in the drier weather. In the high rainfall condition, the 2:1 drain to prevent water saturation in the oil palm rhizosphere by moving some water into the drain. Meanwhile, the disturbed soil horizon (big hole area) was drier than un disturbance immediately due to water removal to deeper layers. We concluded that both big hole and 2:1 drain are a suitable technology for Spodosol soil land especially in preparing palms planting to minimize the negative effect of the hardpan layer for oil palm growth.

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