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Considerations on the degradation of hydrophobic organic chemicals in humic acid solutions

100%

Badora A.

Zeszyty Problemowe Postępów Nauk Rolniczych

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2001

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tom 476

The aim of this research was to show, that sorption and desorption processes of organic hydrophobic compounds on humic acid fraction can influence the microbial degradation rates of contaminants. This study was carried out in the Netherlands in 1996. Chlorinated benzene (pentachlorobenzene QCB) and a polychlorinated biphenyl (2.5-dichlorobiphenyl) were used as a model compounds.

2

Removal of Cr(III) through bread mold fungus

86%

Shoaib A., Aslam N., Athar M. M., Akhtar S., Nafisa, Khurshid S.

Polish Journal of Environmental Studies

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2013

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tom 22

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nr 4

Cr(III) removal ability of indigenous soil fungus of Pakistan (i.e. Rhizopus arrhizus Fisher) was checked through batch trails. Experiments were performed by taking 0.1 g of powdered fungal biomass in 100 mL of metal solution kept at 150 rpm for 3 hours. Results of FTIR spectroscopy revealed that amine (-NH2) and hydroxyl (-OH) groups participated in Cr(III) binding with the fungal biomass. There was an inversely proportional relationship between adsorption efficiency and capacity on increasing initial metal concentration in the range of 20-100 mg/L. The adsorption capacity of fungal biomass was 43.47 mg/g as determined by Langmuir isotherm. High correlation coefficient (R2: 0.99) acquired through Langumir and Frendulich models adequately described the adsorption mechanism on fungal biomass. pH optimization trials in the range of 2-10 exhibited significantly greater adsorption efficiency of 75% at pH 4, while metal removal rate declined with increasing pH. Adsorption/adsorption trials with four acids indicted that maximum desorption of Cr(III) was found with HCl, followed by HNO3, CH3COOH, and H2SO4. Adsorption-based trials summarized that R. arrhizus is a potential and inexpensive biomaterial with viable application in the removal of Cr(III) from the aqueous solution.

3

Influence of amphiphilic anionic and cationic mixture on calcium ion desorption from lipid membranes. I. Experiments with small unilamellar vesicles

86%

Fogt A., Kubica K., Kuczera J.

Polish Journal of Environmental Studies

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1994

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tom 03

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nr 4

This paper studies the influence of equimolar mixtures of biologically-active cationic and anionic amphiphiles (dodecyl-oxymethylene-methyl-morpholinium chloride (DOMM) and one of the series of sodium alkylsulphonates (ASJ with n = 1,2,4,6,8,10,12 and 14 carbon atoms in the alkyl chain) on calcium ion desorption from lecithin liposome membranes. It was shown that by choosing the hydrophobic part of the amphiphilic anion in the mixture one can regulate the efficiency of the amphiphilic cation towards the desorption process. The rate constant of that process strongly depends on the surfactant concentration. The differences in the effectiveness of the different compounds are most distinct at lower concentrations and vanish when the concentration increases. The results are discussed in response to the amphiphilic ion-pair hydrophobicity and their electrical properties. The role of the hypothetical, temporal complexes consisting of the alkylsulphonate anion(s) and calcium cation (ASn-Ca)+ in the calcium ion exchange is discussed. The mechanism of Ca2+ desorption from the surface of the phospholipid bilayer under the simultaneous action of the cationic and anionic detergents is proposed. According to our proposal calcium ion release occurs due to the joint action of the monovalent cationic and anionic detergents in coincidence with a divalent calcium ion. To authenticate the proposed mechanisms of calcium ion release, the shapes of the experimental curves were compared with the theoretical ones obtained by computer simulation using the cellular automata method.

4

Adsorption and desorption of boron on manganese oxide-coated sand as influenced by pH

86%

Wojcik P., Wojcik M.

Journal of Fruit and Ornamental Plant Research

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1999

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tom 07

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nr 4

5

Comparative analysis of desorptive methods used for mass diffusivity estimation

72%

Garbalinska H.

Acta Scientiarum Polonorum. Architectura

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2006

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tom 05

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nr 2

The paper provides a comparative analysis of three methods used to determine Dm diffusivity, which were tested for non-stationary desorption process and referred to various stages of its course. These are: the √t-type method – linked to the initial phase; the logarithmic procedure – for the advanced phase of the process, and the half-time method – referring to the point of time when 50% of mass has been exchanges. The article presents results of desorption process research carried out in the temperature of 20°C and encompassed three mortars characterized by the following water-cement ratios w/c = 0.50, 0.65 and 0.80. Samples of these mortars were conditioned for several months under air relative humidity φ= 97% until the time of reaching moisture equilibrium, and then they were placed in humidity conditions of φ≈ 0%. The values Dm(√t), Dm(ln), Dm(t0.5), obtained through the analyzed desorption process (T = 20°C, φ= 97% → 0%), presented a good conformity of all the three tested methods in the case of all the mortars – from the fully identical results: Dm(t0,5)/Dm(ln) = 1.00 with w/c = 0.80 to the most diversied ones: Dm(t0,5)/Dm(√t) = 1.23 with w/c = 0.65.

6

Właściwości sorpcyjne wybranych gatunków ryżu

72%

Palacha Z., Sas A.

Acta Agrophysica

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2016

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tom 23

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nr 4

W pracy wyznaczono izotermy adsorpcji i desorpcji wody dla wybranych gatunków ryżu metodą statyczno-eksykatorową w temperaturze 25°C, w zakresie aktywności wody od 0,113 do 0,932 (adsorpcja) i od 0,810 do 0,113 (desorpcja). Do badań użyto ryż długoziarnisty biały, brązowy, czerwony, czarny i biały parzony. Stwierdzono, że izotermy adsorpcji i desorpcji wody badanych gatunków ryżu miały kształt sigmoidalny i zgodnie z klasyfikacją Brunauera i in. odpowiadały II typowi izoterm. Do opisu izoterm adsorpcji i desorpcji wody zastosowano modele Oswina, GAB, Lewickiego i Pelega. Modele GAB, Lewickiego i Pelega bardzo dobrze opisywały otrzymane izotermy adsorpcji i desorpcji wody. Obliczony średni błąd kwadratowy (RMS) nie przekroczył 6,5 %. Wszystkie izotermy wykazały pętlę histerezy, przy czym największą pętlą histerezy charakteryzował się ryż biały parzony, a najmniejszą ryż czarny. Zawartość wody w monowarstwie wyznaczona w modelu GAB była większa w procesie desorpcji niż w procesie adsorpcji wody dla wszystkich badanych gatunków ryżu. Ryż biały posiadał największą zawartość wody w monowarstwie w obu procesach (7,182 g wody·100 gˉ¹ s.m. – adsorpcja; 11,162 g wody·100 gˉ¹ s.m. – desorpcja). Największą powierzchnię właściwą posiadał ryż biały (254,7 m²·gˉ¹ s.m.), a najmniejszą ryż biały parzony – 158,0 m²·gˉ¹ s.m.

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Desorption of phosphate [V] ions from brown soil

72%

Bartoszewicz J., Karp E.

Journal of Elementology

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2010

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tom 15

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nr 1

19-29

The objective of the study was to determine, under laboratory conditions, the rate of phosphate (V) ions leaching down brown soil horizons under the influence of redistilled water of pH 6.2. Laboratory tests were conducted to determine the effect of mineral and organic fertilization on phosphate (V) ion concentrations in brown soil horizons before and after extraction with water. The content of desorbed PO4 3– ions was determined in percolating water samples. The results indicate that the quantity of desorbed phosphate (V) ions was affected by the type and rate of fertilization as well as by the dose of the applied solvent. The highest desorption of phosphate (V) ions from the brown soil profile was reported in the treatment fertilized with manure + PK, while the lowest desorption was observed in the plot fertilized with NPK. The maximum desorption of phosphate (V) ions was noted in soil layers at the depths of 0-25 cm and 26-50 cm. In all filtrate samples, PO4 3– values significantly exceeded the minimum quantity required to initiate eutrophication. The highest content of phosphate (V) ions, at 64.8 mg PO4 3–⋅kg–1 soil, was determined in percolating water from the treatment fertilized with slurry rate II (123.8 t⋅ha–1). Percolating water samples collected in the non-fertilized (control) plot were least abundant in phosphate (V) ions (21.7 mg PO4 3–⋅kg–1 soil).

8

Effect of a magnetic field on water desorption from the surface of potato starch

72%

Ocieczek A., Otremba Z.

Acta Agrophysica

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2019

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tom 26

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nr 3

9

The effect of extractive substances soluble in the alcohol-benzene mixture and in alkalies on some hygroscopic properties of birch wood

72%

Krutul D.

Annals of Warsaw Agricultural University. Forestry and Wood Technology

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1992

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tom 43

10

Sorptive behavior and kinetics of carbendazim in mineral soils

72%

Paszko T.

Polish Journal of Environmental Studies

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2006

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tom 15

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nr 3

Studies on adsorption, desorption and reaction kinetics of carbendazim in grey-brown podzolic soil derived from loamy sand (Albic Luvisls), grey-brown podzolic soil derived from silt (Haplic Luvisols) and brown soil derived from sandy clay loam (Haplic Cambisols) were carried out. Five concentrations of carbendazim (5.0, 3.8, 2.6, 1.0 and 0.2 µg · cm⁻³) in 0.01 mol · dm⁻³ CaCl₂ were used for the 24 h batch adsorption experiments; the desorption experiments were performed by replacing equilibrium solutions with 0.01 mol · dm⁻³ CaCl₂ and shaking again for the same period of time. The experimental data showed a good fit to the Freundlich equation (r² in the range 0.988-0.997 for adsorption and 0.980-0.999 for desorption). The values of KFads varied from 5.45 in the sandy to 11.81 in the loess soil, the KFdes from 7.82 in the sandy to 17.87 in the loamy soil; the 1/n values for adsorption and desorption were in the range 0.636-0.812. Adsorption/desorption kinetics were investigated for 1, 2, 4, 6, 8, 10, 24 and 48 h reaction times. The adsorp- tion process in all soils and the desorption process in sandy soil was time-dependent, initially proceeding quickly but within approximately one hour it slowed and ran slowly. useful models for the description of presented experimental kinetic data were the two-site model (r² in the range 0.727-0.994) and the pseudo second-order model (r² in the range 0.636-0.988).

11

Cyclical cadmium adsorption and desorption by activated sludge immobilized on alginate carriers

72%

Kuczajowska-Zadrozna M., Klimiuk E., Wojnowska-Baryla I.

Polish Journal of Environmental Studies

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2004

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tom 13

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nr 2

This paper concerns cadmium desorption in subsequent cycles of adsorption/desorption by chemical sorbents such as 2% sodium alginate, sodium alginate with the addition of poly(vinyl) alcohol (PVA) in the following proportions: 1.5% alginate and 0.5% PVA, 2% alginate and 2% PVA, 2% alginate and 5% PVA, and two kinds of activated sludge immobilized on alginate sorbents. It was proved that adsorption by alginate and alginate with PVA obeys a second-order rate law. The higher the PVA amount in alginate, the lower the reaction rate. Mineral acids such as hydrochloric and sulphuric acids were used as desorption agents. It was observed that all sorbents tested remove cadmium with high and almost constant efficiency from the solution containing 50 mgCd/dm3, whereas desorption effectiveness depended on the kind of sorbents and desorbing agents.

12

Desorption-ionization on silicon for small molecules: a promising alternative to MALDI TOF

72%

Kraj A., Dylag T., Gorecka-Drzazga A., Bargiel S., Dziuban J., Silberring J.

Acta Biochimica Polonica

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2003

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tom 50

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nr 3

A method has been developed for laser desorption/ionization of catecholamines from porous silicon. This methodology is particularly attractive for analysis of small molecules. MALDI TOF mass spectrometry, although a very sensitive technique, utilizes matrices that need to be mixed with the sample prior to their analysis. Each matrix produces its own background, particularly in the low-molecular mass region. Therefore, detection and identification of molecules below 400 Da can be difficult. Desorption/ionization of samples deposited on porous silicon does not require addition of a matrix, thus, spectra in the low-molecular mass region can be clearly readable. Here, we describe a method for the analysis of catecholamines. While MALDI TOF is superior for proteomics/peptidomics, desorption/ionization from porous silicon can extend the operating range of a mass spectrometer for studies on metabo- lomics (small organic molecules and their metabolites, such as chemical neurotransmitters, prostaglandins, steroids, etc.).

13

Desorption of heavy metals by barium cation in Polish mineral soils. Part I. The influence of barium cation

72%

Gaszczyk R., Jackowska I.

Polish Journal of Environmental Studies

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1996

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tom 05

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nr 5

The process of desorption of Cd2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, Mn2+, Ni2+, Pb2+, and Zn2+ cations in three kinds of Polish mineral soils (Podzoluvisols, Orthic Luvisols, and Eutric Cambisols) were examined. Desorption was carried out by means of a dynamic method through eluting a soil column containing heavy metal ions with a barium chloride solution. Liming of the Podzoluvisols and Eutric Cambisols caused a decrease in the degree of desorption of heavy metal cations (with the exception of Cd2+, Zn2+, and Mn2+ - Podzoluvisols; as well as Fe2+, and Fe3+ - Eutric Cambisols). Liming of the Orthic Luvisols caused differences in the degrees of desorption of heavy metal cations in dynamic conditions.

14

Proteomika w badaniu drobnoustrojów

58%

Szczepanska E., Robak M.

Acta Scientiarum Polonorum. Biotechnologia

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2013

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tom 12

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nr 4

We wstępie do artykułu przedstawiono stosunkowo nową dziedzinę badań – proteomikę, w obrębie której analizowane są: skład, budowa i funkcja białek oraz zachodzące pomiędzy nimi interakcje. W kolejnych rozdziałach opisano najważniejsze techniki analityczne proteomiki: elektroforezę dwukierunkową, metodę laserowej desorpcji/jonizacji próbki wspomaganej matrycą z analizatorem czasu przelotu (MALDI-TOF) oraz elektrorozpraszanie jonizacyjne (ESI, electrospray ionization). W celu przybliżenia zagadnień związanych z proteomiką w opracowaniu zaprezentowano przykłady analizy proteomu drobnoustrojów, w tym wybranych patogenów (Staphylococcus aureus, Vibrio cholerae, Bacillus subtilis, Mycobacterium avium, Borrelia ssp., Aspergillus flavus). Na podstawie wyników badań proteomu udokumentowano możliwość identyfikacji gatunku oraz badanie metabolizmu mikroorganizmu i interakcji gospodarz–patogen, a nawet możliwość różnicowania potencjału enzymatycznego mikroorganizmów utylizujących surowce ligninocelulozowe. W podsumowaniu zaznaczono potencjał analizy proteomicznej, przydatnej w wielostronnej charakterystyce drobnoustrojów.

15

Sorpcja jonów fosforanowych na glebie murszowatej

58%

Bartoszewicz J.

Acta Academiae Agriculturae ac Technicae Olstenensis. Agricultura

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1995

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tom 60

35-42

Zbadano sorpcję jonów fosforanowych pochodzących z wodnych roztworów H3P04, KH2PO4, K2HPO4, K3PO4 na glebie murszowatej oraz desorpcję jonów fosforanowych z tej gleby za pomocą elektrodializy. Stwierdzono, że ilość zasorbowanych i zdesorbowanych jonów fosforanowych zależy od rodzaju i stężenia związku z którego jony pochodziły. Ilość jonów fosforanowych zdesorbowanych elektrodialitycznie zależy od ilości użytej energii elektrycznej.

16

Sorption, degradation and leaching of the phenoxyacid herbicide MCPA in two agricultural soils

58%

Hiller E., Cernansky S., Zemanova L.

Polish Journal of Environmental Studies

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2010

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tom 19

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nr 2

315-321

MCPA is the phenoxyacid herbicide widely used for weed control in cereals in Slovakia. However, little is known on the processes governing the environmental fate of MCPA in soils from Slovakia. Laboratory experiments were performed to evaluate the sorption, desorption, degradation, and leaching behavior of MCPA in two agricultural soils with high sand content and different soil organic carbon content. The extent of MCPA sorption was higher in chernitsa than that in regosol, in accordance with the higher organic carbon content of the former soil than the latter. MCPA was readily desorbed from soils with 10 mmol l⁻¹ CaCl₂ solution with the desorption rate ranging from 44.5 to 77.5% of the sorbed MCPA. The half-life values showed that the degradation of MCPA was fast in chernitsa (t1/2 = 2.2 days) and almost six times faster than in regosol (t1/2 =11.7 days). Leaching tests, performed in manually packed soil columns, indicated that MCPA was more mobile in regosol than in chernitsa with 16.44% of the applied MCPA recovered in the leachates of regosol, and 1.12% found in the leachates of chernitsa. Thus, differences in the leaching behavior of MCPA coincided well with the results of the batch sorption and degradation experiments.

17

Hygroskopizitat von Papier

58%

Matejak M., Przybysz P.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2012

|

tom 79

18

Phosphate desorption from sediments in the Pomeranian Bay [Southern Baltic]

58%

Frankowski L., Bolalek J.

Oceanological Studies

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1997

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tom 26

|

nr 1

19

The effect of poly[vinyl alcohol] on cadmium adsorption and desorption from alginate adsorbents

58%

Klimiuk E., Kuczajowska-Zadrozna M.

Polish Journal of Environmental Studies

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2002

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tom 11

|

nr 4

Cadmium adsorption onto and desorption from sodium alginate and sodium alginate with poly(vinyl alcohol) (PVA) were studied. Intraparticular diffusion was demonstrated to limit adsorption kinetics during the first 20 min of process. The Deff value was dependent on adsorbent chemical composition and ranged from 3.35 ´ 10-10 m2/s to 1.86 ´ 10-10 m2/s for the 1.5% alginate with 0.5% PVA and for the 2% alginate with 5% PVA, respectively. At equilibrium the adsorption was more effective onto the 2% alginate and was lower for the alginate sorbent containing poly(vinyl alcohol). The dimensionless separation factor RL increased from 0.26 to 0.68 for the 2% alginate and the 2% alginate + 5% PVA, respectively. The maximum adsorption capacities in Langmuir isotherm for both the 2% and 1.5% alginate with 0.5% PVA were similar and were 176 and 178 mg/g dry weight, respectively. However, the adsorption capacity decreased to 48 mg/g dry weight for the 2% alginate with the 5% PVA (in proportion to the polymer amount increase in the adsorbent). Cadmium desorption was more effective for nitric acid than for sulfuric and hydrochloric acids (desorption pH 2.2). More cadmium was desorbed from 2% alginate with 5% PVA than from 2% alginate or 1.5% alginate with 0.5% PVA.

20

Effects of secondary transformation of peat-moorsh soils on their physical properties

58%

Slawinski C., Sokolowska Z., Walczak R.

Acta Agrophysica

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2000

|

tom 26

Detoriation of water conditions in the peat soils are closely related to the transformations that take place in the structure of organic soil mass. Changes in water relations together with an increased access of air enable various physical, chemical and biological processes to take place. This, in turn, leads to changes in organic soil mass and soil mass transformation into moorsh. The scope of changes and their rate depends also on the properties of the original materials. Amorphic peats are most susceptible to secondary tranformations, whereas fibrous peats undergo moorsing slower. peat formations after secondary transformations have been divided into 5 groupsassuming numerical values of water absorptivity as the basic for the division. This index expresses the ratio between the lowest water absorptivity of a given formation to its absorptivity in the fresh state.The aim of the present work was to evaluate in what way type of moorsh and degree of its secondary transformation influence some of its physical properties, i.e., retention curves and water conductivity, absorption level (wetting) and desorption (drying) of steam as well as its specific surface area. The study object included peaty moorshes and proper moorshs originating from peats formations at various stages of decomposition. The soil material originated from the region of Polesie Lubelskie.

Ograniczanie wyników

Considerations on the degradation of hydrophobic organic chemicals in humic acid solutions

Removal of Cr(III) through bread mold fungus

Influence of amphiphilic anionic and cationic mixture on calcium ion desorption from lipid membranes. I. Experiments with small unilamellar vesicles

Adsorption and desorption of boron on manganese oxide-coated sand as influenced by pH

Comparative analysis of desorptive methods used for mass diffusivity estimation

Właściwości sorpcyjne wybranych gatunków ryżu

Desorption of phosphate [V] ions from brown soil

Effect of a magnetic field on water desorption from the surface of potato starch

The effect of extractive substances soluble in the alcohol-benzene mixture and in alkalies on some hygroscopic properties of birch wood

Sorptive behavior and kinetics of carbendazim in mineral soils

Cyclical cadmium adsorption and desorption by activated sludge immobilized on alginate carriers

Desorption-ionization on silicon for small molecules: a promising alternative to MALDI TOF

Desorption of heavy metals by barium cation in Polish mineral soils. Part I. The influence of barium cation

Proteomika w badaniu drobnoustrojów

Sorpcja jonów fosforanowych na glebie murszowatej

Sorption, degradation and leaching of the phenoxyacid herbicide MCPA in two agricultural soils

Hygroskopizitat von Papier

Phosphate desorption from sediments in the Pomeranian Bay [Southern Baltic]

The effect of poly[vinyl alcohol] on cadmium adsorption and desorption from alginate adsorbents

Effects of secondary transformation of peat-moorsh soils on their physical properties