Wyniki wyszukiwania - Biblioteka Nauki

1

Selective adsorption of trypsin using molecularly imprinted polymers prepared with PEG-based hydrogels containing anionic functional monomers

100%

Kubo T. , Arimura S. , Naito T. , Otsuka K.

Molecular Imprinting

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2014

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tom 2

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nr 1

EN

Molecularly imprinting (MI) hydrogels for selective adsorption of trypsin are reported. The trypsin imprinted hydrogels were prepared using a polyethylene glycol (PEG)-based dimethacrylate as a crosslinker and anionic functional monomers. The hydrogel prepared without any functional monomers showed significantly low ability to adsorb a variety of proteins. We optimized the concentration and the length of PEG units of the crosslinkers to achieve the complete removal of the template molecule and suitable selective adsorption. Additionally, the functional monomers chosen were anionic since the template, trypsin, is a basic protein. The adsorption tests for proteins, done on the prepared MI gels, indicated that the MI gel prepared with sodium allyl sulfonate (AS) as a functional monomer showed much higher selective adsorption for trypsin, even though a mixture of trypsin and cytochrome c was used as the protein solution. The selective adsorption was more effective in a NaCl solution in which the non-specific adsorption by a sulfonate is suppressed, similarly to our findings in a previous study. The MI gel prepared with acrylic acid also showed the selectivity, although the adsorption strength was lower than that of the MI gel containing AS. We believe that the present study constitutes the first approach for the selective adsorption of trypsin using PEG-based hydrogels.

2

Chaoticity analysis of the current through pure, hydrogenated and hydrophobically modified PEG-Si thin films under varying relative humidity

100%

Atak K. , Aybar O. , Şahin G. , Hacınlıyan A. , Skarlatos Y.

Open Physics

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2009

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tom 7

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nr 3

568-574

EN

Polyethylene Glycol has an irregular current characteristic under constant voltage and slowly varying relative humidity. The current through a thin film of Gamma-isocyanatopropyltriethoxysilane added Polyethylene glycol (PEG-Si), its hydrogenated and hydrophobically modified forms, as a function of increasing relative humidity at equal time steps is analyzed for chaoticity. We suggest that the irregular behavior of current through PEG-Si thin films as a function of increasing relative humidity could best be analyzed for chaoticity using both time series analysis and detrended uctuation analysis; the relative humidity is kept as a slowly varying parameter. The presence of more then one regime is suggested by the calculation of the maximal Lyapunov exponents. Furthermore, the maximal Lyapunov exponent in each of the regimes was positive, thus confirming the presence of low dimensional chaos. DFA also confirms the presence of at least two different regimes, in agreement with the behavior of the maximal Lyapunov exponent in the time series analysis. We also suggest that the irregular behavior of the current through PEG-Si can be reduced by hydrogenating and hydrophobically modifying PEG-Si and the improvement in stability can be confirmed by our study.

3

Minimizing the explosion enthalpy of ammonium nitrate with polyethylene glycol and carboxymethyl cellulose to prevent terrorist attacks

88%

Gezerman A. O. , Gezerman A. O.

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4

Self-assembling micelles obtained from PLLA/PEG and PDLA/PEG block copolymers in aqueous solutions

88%

Wu X. , Li S.

Engineering of Biomaterials

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2012

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tom Vol. 15, no. 113

6--8

EN

A series ofpolylactide-poly(ethylene glycol) (PLA- PEG) block copolymers were synthesized by ring-opening polymerization of L- or D-lactide in the presence of mono- or dihydroxyl PEG, using nontoxic zinc lactate as catalyst. Micelles were then prepared by direct dissolution of the obtained copolymers in aqueous medium without heating or using any organic solvents. Aqueous gel permeation chromatography and dynamic light scattering measurements were carried out to characterize the resulting micelles. Generally, mixed micelles containing both PLLA/PEG and PDLA/PEG copolymers appear lager and more compact compared to single ones. However, the size of mixed micelles is smaller than that of single ones which exhibit an anisotropic structure since stereocomplexation disfavors the formation of anisotropic micelles. The copolymer parameters such as structures, molar mass and PEG fraction strongly influence the formation of anisotropic micelles, and thus lead to various micellar sizes.

5

Hg (II) extraction in a PEG-based aqueous two-phase system in the presence of halide ions. I. Liquid phase analysis

88%

Bulgariu L. , Bulgariu D.

Open Chemistry

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2006

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tom 4

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nr 2

246-257

EN

The partition behaviour of Hg (II) was studied in an aqueous polyethylene glycol (PEG) - (NH4)2SO4 two-phase system as a function of halide, halide concentration, and pH. For a system prepared by mixing equal volumes of 40 % (w/w) PEG (1550) with 40 % (w/w) (NH4)2SO4, Hg(II) remains almost exclusively in the salt-rich phase. The addition of NaX (X = Cl−, Br−, I−) enhances Hg (II) partition into the PEG-rich phase due to the formation of halide complexes. The efficiency of halide extractants increases in the order: Cl− < Br− < I−. Mercury extraction is improved at lower halide ion concentration by higher stock salt solution acidity. From the distribution coefficients determined as a function of halide ion concentration, the extracted species were identified. The Hg (II) extractability is determined by the type and stability of the Hg (II) halide species, and depends on the stock salt solution acidity. The observed behaviour is discussed and a possible extraction mechanism is proposed.

6

Characterization of SnO2/TiO2 with the Addition of Polyethylene Glycol via Sol-Gel Method for Self-Cleaning Application

88%

Halin D. S. C. , Azliza A. , Razak K. A. , Abdullah M. M. A. B. , Salleh M. A. A. M. , Wahab J. A. , Chobpattana V. , Kaczmarek Ł. , Nabiałek M. , Jeż B.

Archives of Metallurgy and Materials

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2023

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tom Vol. 68, iss. 1

243--248

EN

TiO2 is one of the most widely used metal oxide semiconductors in the field of photocatalysis for the self-cleaning purpose to withdraw pollutants. Polyethylene glycol (PEG) is recommended as a stabilizer and booster during preparation of water-soluble TiO2. Preparation of SnO2/TiO2 thin film deposition on the surface of ceramic tile was carried out by the sol-gel spin coating method by adding different amount of PEG (0g, 0.2g, 0.4g, 0.6g, 0.8g) during the preparation of the sol precursor. The effects of PEG content and the annealing temperature on the phase composition, crystallite size and the hydrophilic properties of SnO2/TiO2 films were studied. The X-ray diffraction (XRD) spectra revealed different phases existed when the films were annealed at different annealing temperatures of 350°C, 550°C and 750°C with 0.4 g of PEG addition. The crystallite sizes of the films were measured using Scherrer equation. It shows crystallite size was dependent on crystal structure existed in the films. The films with mixed phases of brookite and rutile shows the smallest crystallite size. In order to measure the hydrophilicity properties of films, the water contact angles for each film with different content of PEG were measured. It can be observed that the water contact angle decreased with the increasing of the content of PEG. It shows the superhydrophilicity properties for the films with the 0.8 g of PEG annealed at 750°C. This demonstrates that the annealed temperature and the addition of PEG affect the phase composition and the hydrophilicity properties of the films.

7

Improved performance of muskmelon [Cucumis melo] seeds with osmoconditioning

88%

Singh G. , Gill S. S. , Sandhu K. K.

Acta Agrobotanica

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1999

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tom 52

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nr 1-2

EN

Seeds of muskmelon (Cucumis melo) cultivars viz. Pb. Hybrid and Pb. Sunehri were osmoconditioned with Polyethylene glycol j(PEG) and KNO, solutions to enhance their performance at low temperature. Osmoconditioning both with PEG 6000 and KNO3 increased per cent germination, speed of germination, vigour in terms of dry weight and length of the seedlings and root/shoot ratios. KNO3 priming recorded more pronounced effect in all the above mentioned parameters. Other vigour parameters such as electrical conductance of seed leachates was decreased with osmoconditioning while dehydrogenase activity was enhanced. Osmoconditioning resulted in increased activity of amylases.

PL

Nasiona dwóch odmian melona (Cucumis melo) byty osmokondycjonowane glikolem polietylenowym ( PEG ) i KNO3 dla poprawienia ich reakcji na niskie temperatury. Użycie obu wymienionych preparatów zwiększyło procent i szybkość kiełkowania, wigor roślin określany ich suchą masą i wielkością siewek oraz stosunek korzeń/pęd. KNO3 miał bardziej wyraźny wpływ na wszystkie wymienione cechy. Inne parametry wigoru, np. przewodnictwo elektryczne cieczy otrzymanej w wyniku przemywania nasion ulegało obniżeniu pod wpływem osmokondycjonowanía, podczas gdy aktywność dehydrogenazy i amylaz była zwiększona.

8

A comparison of oxygen diffusion rates in sand moistened with water or PEG 20000 solution

88%

Hiller S. , Dexter A. R.

International Agrophysics

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1997

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tom 11

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nr 3

9

Efficiency of non-ionic surfactant removal in biological sewage treatment plants

88%

Traczyk L. , Szymanski A. , Wyrwas B. , Jaroszynski T. , Lukaszewski Z.

Polish Journal of Environmental Studies

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2006

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tom 15

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nr 3

EN

The removal of non-ionic surfactants (NS), as well as a long-chained ethoxylates, short-chained NS and poly(ethylene glycols)(PEG), was investigated in two sewage treatment plants (STP) of the activated sludge type and one trickling filter type. The indirect tensammetric method (ITM), and the ITM combined with the Bismuth Active substances (BiAS) separation scheme (BiAS-ITT) were used for the determination of NS and their metabolites. on average, 85% reduction of total Ns was determined in the activated sludge type STP and 53% reduction in the case of the trickling filter type STP. significant concentrations of NS metabolites (short-chained NS and PEG) were determined in raw sewage, which indicate that NS biodegradation had already started in the sewer system. Both tensammetric methods prove to be a useful tool in monitoring Ns and their metabolites in STP.

10

Properties of particleboards resinated with PMDI modified with polyethylene glycols

75%

Dziurka D. , Jablonski M. , Mirski M.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2007

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tom 06

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nr 4

EN

The study investigated properties of particleboards resinated with PMDI modified with polyethylene glycols with varying molar masses (PEG 200 and 400). The conducted investigations showed that PMDI resin modification with both PEG 200 and PEG 400 causes an increase in mechanical properties of manufactured boards. In turn, modulus of elasticity decreases with an increase in plasticity of the modified resin. Then, water resistance of the tested boards, measured by their tear resistance after the boiling test, irrespective of the type and the amounts of applied modifiers, is very high and considerably exceeds the requirements specified in the respective standard. Particleboards exhibiting better mechanical properties and considerably improved water resistance may be obtained by the modification of PMDI resin with polyethylene glycol of a higher molar mass.

PL

W pracy zbadano właściwości płyt wiórowych zaklejanych żywicą izocyjanianową modyfikowaną polietylenoglikolami o różnych masach molowych (PEG 200 i PEG 400) w ilościach 0,005-0,025 mola na 100 g suchej masy żywicy. Z przeprowadzonych badań wynika, iż modyfikacja PMDI wybranymi polietylenoglikolami wpływa na wzrost właściwości wytrzymałościowych wytworzonych płyt. Natomiast moduł sprężystości ulega zmniejszeniu ze względu na wzrost plastyczności modyfikowanej żywicy. Z kolei wodoodporność badanych płyt, mierzona ich wytrzymałością na rozrywanie po próbie gotowania, niezależnie od rodzaju i ilości polietylenoglikolu jest bardzo duża i znacznie przekracza wymagania określone odpowiednią normą.

11

Evaluation of cell membrane injury in caraway [Carum carvi L.] genotypes in water deficit conditions

75%

Seidler-Lozykowska K. , Bandurska H. , Bocianowski J.

Acta Societatis Botanicorum Poloniae

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2010

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tom 79

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nr 2

95-99

EN

The aim of the study was to evaluate the resistance of caraway genotypes to water deficit based on the estimation of cell membrane stability (CMS) in leaves using polyethylene glycol (PEG) test. In 2007 and 2008, 25 selected caraway genotypes, originating from European botanical gardens (18), cultivars (2) and our own breeding strains (5), were tested. The plant material was collected from the experimental field. The obtained results showed highly significant differences in cell membrane injuries (p = 0.001) among investigated genotypes. The rank of genotypes in membrane injury index in 2007 was similar to that of 2008. Caraway genotypes originating from Warsaw (49.4%), Cracow (45.3%), Reykiavik (39.9%), Berlin (23.8%), Wisley (22.7%) and strains 9/2 (23.7%), 60/8 (22.2%) exhibited a high level of injury, which showed weak CMS and their high sensitivity to drought. The lowest extent of membrane injury was observed in genotypes originating from Bayreuth (4.2%), Ulm (4.4%), Cluj (5.5%), Lousanne (6.8%) and cultivar "Kończewicki" VI/4 (6.2%), which proves low sensitivity of these genotypes to water deficit and cell membrane stability. These genotypes may be used in further breeding program to improve caraway resistance to drought.

12

Influence of polyethylene glycol concentration on morphology of polypropylene membranes

75%

Lenart P. , Kotra-Konicka K. , Kalbarczyk J.

Challenges of Modern Technology

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2014

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tom Vol. 5, no. 2

9--14

EN

This work studied the influence of polyethylene glycol (PEG) concentration on the polypropylene membranes morphology. Polypropylene membranes were modified with argon plasma and then immersed in PEG solution with various concentration between 50-80%. Changes of membranes morphology were observed by scanning electron microscope, Fourier transform infrared spectroscopy and contact angle measurements.

13

Motor behaviour of Amoeba proteus during glutaraldehyde fixation

75%

Grebecka L. , Grebecki A. , Hrebenda B.

Acta Protozoologica

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1987

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tom 26

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nr 1

14

Elimination of polyethylene glycol from aqueous solution using activated carbon

75%

Gajdos L. , Pietrelli L. , Ciccarello A. , Derco J.

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nr 3

385-388

EN

The present study looks at the adsorption of polyethylene glycol onto activated carbon with the different molecular weight. The amount of PEG adsorbed on activated carbon depends on temperatures and pH. The adsorption capacities were determined through the adsorption isotherms. The results of the adsorption isotherm and kinetic studies show that the adsorption process can be well described with the Langmuir model. After linearization of the Arrhenius equation the activated energy had been estimated.

15

Physiological adaptations to osmotic stress and characterization of a polyethylene glycol-responsive gene in Braya humilis

75%

Lirong W. , Pengshan Z. , Xin Z. , Xiaopeng W. , Xiaofei M. , Yi L.

Acta Societatis Botanicorum Poloniae

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2016

|

tom 85

|

nr 1

EN

Braya humilis (Brassicaceae) is a widely distributed plant in arid and semi-arid regions of northern Asia. This plant is well adapted to extremely arid conditions and is a promising candidate species to discover novel drought tolerance strategies. However, not much information about the mechanism(s) mediating drought resistance in this species is currently available. Therefore, the present study aimed to characterize the physiological traits and expression patterns of a polyethylene glycol (PEG)-responsive gene in B. humilis responding to different levels of osmotic stress induced by PEG-6000. Several important physiological parameters were examined, including the levels of relative water content, soluble protein, malondialdehyde, and antioxidant enzyme activity. A tolerance threshold between 20 and 30% PEG-6000 was identified for B. humilis. The water status and oxidative damage below this threshold were maintained at a relatively constant level during the 12 h of treatment. However, once the threshold was exceeded, the water status and oxidative damage were obviously affected after treatment for 4 h. The soluble protein results suggest that B. humilis maintains a vigorous resistance to osmotic stress and that it may play a greater role in osmotic regulation at late stages of stress. Moreover, superoxide dismutase and catalase may be important at preventing oxidative damage in plants at early stages of stress, while peroxidase may be more involved in some biological processes that resist osmotic stress at the late stage, especially in severely damaged plants. Furthermore, a PEG-responsive gene, BhCIPK12, was identified by differential display reverse transcription-polymerase chain reaction (PCR), cloned, and characterized by quantitative real-time PCR. We hypothesized that this gene may play an important role in mediating osmotic stress or drought resistance in plants. Altogether, these results provide valuable insights into the mechanism(s) mediating drought tolerance in B. humilis.

16

Encapsulation of L-ascorbic acid via polycaprolactone-polyethylene glycol-casein bioblends

75%

Ozsagiroglu E. , Guvenilir Y. A.

Polish Journal of Chemical Technology

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2015

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tom Vol. 17, nr 4

32--36

EN

The aim of this study was to encapsulate, L-ascorbic acid, in biopolymers in order to obtain (i) enhancing its encapsulation efficiency (ii) increasing drug release ratio using different pH mediums. Microparticles based on polycaprolactone, polyethylene glycol and casein are prepared by spray drying technique. Microparticles are in vitro characterized in terms of yield of production, particle size, morphology, encapsulation efficiency, and drug release. In this manner, the importance of the study is producing of a stable and effective drug encapsulation system by PCL-PEG-CS polymer mixture by spray dryer. We achieved minimum 27.540±0.656 μm particle size with 0.512 m2/g surface area, 84.05% maximum drug loading, and 68.92% drug release ratio at pH 9.6. Release profiles are fitted to previously developed kinetic models to differentiate possible release mechanisms. The Korsmeyer–Peppas model is the best described each release scenario, and the drug release is governed by non-Fickian diffusion at pH 9.6. Our study proposed as an alternative or adjuvants for controlling release of L-ascorbic acid.

17

The effects of vitamin C-polyethylene glycol complex on growth performance and immunity in broiler chickens

75%

Hahn T. W. , Lohakare J. D. , Shim Y. H. , Han K. N. , Won H. K. , Park Y. H. , Chae B. J.

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tom 14

|

nr 1

18

Repeated injections of peg-pe liposomes generate anti-peg antibodies

75%

Sroda K. , Rydlewski J. , Langner M. , Kozubek A. , Grzybek M. , Sikorski A. F.

Cellular and Molecular Biology Letters

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2005

|

tom 10

|

nr 1

19

Influence of fungicide treatment and osmoconditioning with polyethylene glycol on germination of graded carrot seeds

75%

Biniek A.

Vegetable Crops Research Bulletin

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2001

|

tom 55

20

Self-curing concrete under sulfate attack

63%

Bashandy A. A.

Archives of Civil Engineering

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2016

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tom Vol. 62, nr 2

3--18

EN

Self-curing concrete SC is a concrete type that can be cured without using any external curing regimes. It can perform by several methods such as using lightweight aggregate or chemical agents. In this research chemical curing agent is used to produce SC. This paper reports the results of a research study conducted to evaluate the effect of sulfates on the performance of self-curing concrete compared to ordinary concrete. Samples are immersed in sodium sulfate Na2S04 solution of 4% concentration. Results are measured in terms of compressive strength, tensile strength, flexural strength and mass loss. It was found that the rate of strength loss is noticed at ordinary concrete compared to SC concrete. Sulfate resistance is improved when using self-curing concrete. This improvement appears to be dependent on using a chemical curing agent.

PL

Niniejsza praca przedstawia wyniki badania przeprowadzonego w celu ocenienia wpływu siarczanów na beton samoutwardzalny, w porównaniu z betonem zwykłym. Beton samoutwardzalny SC, jest typem betonu, który utwardzany jest bez jakichkolwiek zewnętrznych systemów utwardzania. Można to osiągnąć stosując kilka metod, jak użycie lekkiego kruszywa, czy też środków chemicznych. W tym badaniu, do produkcji SC wykorzystano chemiczny środek utwardzający. Przygotowano dwie mieszanki betonu. Pierwszą mieszanką SC był beton samo-utwardzalny oparty na poprzednich badaniach. Próbki zostały odlane przy wykorzystaniu zwykłego cementu portlandzkiego, zgniecionego dolomitu o maksymalnym rozmiarze nominalnym 12,5 mm, sortowanego piasku ze współczynnikiem delikatności 2,40, pyłem krzemionkowym jako 15% zawartości cementu, super-plastyfikatorem "Addicrete BVF" jako 0,07% zawartości cementu, chemicznym utwardzaczem "Glikolem polietylenowym PEG200" jako 2% składniku cementu oraz z wodą kranową do pierwszej mieszanki betonu. Druga mieszanka betonu CC, jest zwyczajnie utwardzaną mieszanką, o tych samych proporcjach co mieszanka samoutwardzająca, ale bez dodatku chemoutwardzacza "PEG200", aby dać możliwość porównania obu mieszanek. Próbki zostały odlane przy wykorzystaniu dwóch użytych mieszanek, SC i CC. Drugą mieszanką betonu była CC, utwardzana przez 28 dni.