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Wyszukujesz frazę "polyethylene glycol" wg kryterium: Temat


Tytuł:
Self-assembling micelles obtained from PLLA/PEG and PDLA/PEG block copolymers in aqueous solutions
Autorzy:
Wu, X
Li, S.
Powiązania:
https://bibliotekanauki.pl/articles/285984.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów
Tematy:
polylactide
polyethylene glycol
stereocomplexation
self-assembly
anisotropy
Opis:
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.
Źródło:
Engineering of Biomaterials; 2012, 15, 113; 6-8
1429-7248
Pojawia się w:
Engineering of Biomaterials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of PEG 4000 on maturation, germination and conversion frequency of Picea abies and P. omorika somatic embryos
Autorzy:
Wawrzyniak, M.
Hazubska-Przybyl, T.
Obarska, A.
Bojarczuk, K.
Powiązania:
https://bibliotekanauki.pl/articles/951243.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
polyethylene glycol
somatic embryogenesis
somatic seedling
maturation
germination
coniferous species
Picea abies
Picea omorika
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2015, 96, 1
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Theoretical Study of Polyethylene Glycol Polynitrates as Potential Highly Energetic Plasticizers for Propellants
Autorzy:
Wang, Guixiang
Xu, Yimin
Zhang, Wenjing
Gong, Xuedong
Powiązania:
https://bibliotekanauki.pl/articles/358877.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
polyethylene glycol polynitrates
density functional theory
density
specific impulse
stability
Opis:
Polyethylene glycol polynitrates may be used as plasticizers in propellants. In this study, ten derivatives of ethylene glycol dinitrate were investigated using the density functional theory method. The fitted densities (ρ’exp.) were obtained and were very close to the experimental values. The detonation properties were predicted using the modified Kamlet-Jacobs equations and the specific impulse (Is) was evaluated according to the largest exothermic principle. A new indicator, K = Is · ρ’exp., is proposed to evaluate the energetic characteristics of the plasticizers. Thermal stability is discussed by calculating the bond dissociation energies or energy barriers. The O−NO2 bond is the trigger bond for all of the compounds studied. Considering the energetic properties and stability, diethylene glycol tetranitrate, triethylene glycol hexanitrate, tetraethylene glycol octanitrate, pentaethylene glycol decanitrate and hexaethylene glycol dodecanitrate are potential energetic plasticizers for solid propellants. The influences of the −O−CH2−CH2− and −O−CH(ONO2)−CH(ONO2)− groups are also discussed, which will be helpful for the design of new highly energetic plasticizers by modifying the structures as required.
Źródło:
Central European Journal of Energetic Materials; 2019, 16, 2; 194-215
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Technological aspects of synthesis of poly(ethylene glycol) mono-1-propenyl ether monomers
Autorzy:
Urbala, Magdalena
Powiązania:
https://bibliotekanauki.pl/articles/779637.pdf
Data publikacji:
2020
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
polyethylene glycol allyl ether
1-propenyl ether
isomerization
ruthenium complex
photopolymerization
Opis:
For the first time, the technological aspects of the highly productive and selective synthesis of UV-reactive poly(ethylene glycol) mono-1-propenyl ether monomers was developed. The solvent-free isomerization of model commercial available 2-allyloxyethanol and allyloxypoly(ethylene glycol) derivatives, type Allyl–[OCH2CH2]n–OH, n = 1–5, into a 1-propenyl derivative under the homogeneous catalysis conditions using the ruthenium complexes were evaluated. The effect of a various reaction conditions (i.e. the concentration of [Ru] complex, the reaction temperature, reaction gas atmosphere) together with trace amounts of allyl hydroperoxides formed via autoxidation reaction of allyl substrates on the productivity of catalyst was examined in detail. Moreover, the significant role of the allyl substrate structures on the catalytic activity of ruthenium catalysts were also recognized. The optimal parameters of the scaled-up synthesis together with productivity of catalyst were first established.
Źródło:
Polish Journal of Chemical Technology; 2020, 22, 3; 55-63
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modyfikacja warstwy wierzchniej fosforanów wapnia polimerami biodegradowalnymi
Surface modification of calcium phosphates by biodegradable polymers
Autorzy:
Szubert, M.
Adamska, K.
Voelkel, A.
Buchwald, T.
Szybowicz, M.
Powiązania:
https://bibliotekanauki.pl/articles/285387.pdf
Data publikacji:
2012
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów
Tematy:
hydroksyapatyt
ß-fosforan trójwapniowy
modyfikacja warstwy wierzchniej
glikol polioksyetylenowy
polihydroksymaślan
bioaktywność
hydroxyapatite
surface modification
polyethylene glycol
polyhydroxybutyrate
bioactivity
β-tricalcium phosphate
Opis:
Celem pracy była modyfikacja warstwy wierzchniej biomateriałów ceramicznych należących do grupy fosforanów wapnia-hydroksyapatyt (HA) oraz ß-fosforan trójwapniowy (ß-TCP), a następnie określenie wybranych właściwości biologicznych otrzymanych materiałów. Jako modyfikatory zastosowano dwa polimery biodegradowalne: glikol poli(oksy etylenowy) (PEG) oraz polihydroksymaślan (PHB). Pomyślność procesu modyfikacji potwierdzono za pomocą spektroskopii w podczerwieni (FT-IR; ATR) oraz spektroskopii Ramana. Biomateriały przed modyfikacją oraz po modyfikacji poddano testom określającym ich zdolność do degradacji oraz narastania hydroksyapatytu. Test degradacji przeprowadzono zanurzając materiały w roztworze buforowym tris-HCl przez okres czterech tygodni, w ciągu których dokonywano pomiaru masy w odstępach tygodniowych. W celu zbadania zdolności wzrostu hydroksyapatytu na powierzchni materiałów, próbki inkubowano w płynie symulującym osocze krwi (SBF) w temperaturze 37oC przez miesiąc. Zmiany zachodzące na powierzchni badanych materiałów rejestrowano w odstępach tygodniowych za pomocą skaningowego mikroskopu elektronowego (SEM) oraz spektroskopii w podczerwieni. Na podstawie przeprowadzonych badań stwierdzono, że szybkość procesu degradacji (obliczona na podstawie procentowego ubytku masy) biomateriałów modyfikowanych zwiększyła się w przypadku hydroksyapatytu zarówno modyfikowanego PEG jak i PHB, natomiast w przypadku ß-TCP szybkość ta była na porównywalnym poziomie w porównaniu do materiału wyjściowego. Analiza obrazów wykonanych z wykorzystaniem SEM wykazała widoczne zmiany w morfologii powierzchni modyfikowanych materiałów. Zmiany te mogą świadczyć o właściwościach osteoindukcyjnych tych biomateriałów.
The main aim of this study is surface modification of ceramic biomaterials, belong to calcium phosphates group-hydroxyapatite (HA) and ß-tricalcium phosphate (ß-TCP)- and furthermore selected biological properties of obtained materials is determined. Polyethylene glycol (PEG) and polyhydroxybutyrate (PHB) are used as modifiers. The process of surface modification of biomaterials is confirmed by means of infrared spectroscopy (FT-IR; ATR) and Raman spectroscopy. In presented study the obtained powder materials are formed on pellets and incubated in SBF (simulated body fluids solution) at body temperature. Formation of apatite layer was evaluated by means of Scanning Electron Microscope (SEM). The degradation behavior was carried out at 37oC for up to 28 days at pH 7.4 using Tris-HCl solution, and is referred to as simulation solution testing. The samples were incubated for 7, 14, and 28 days for the both simulation solution testing, using triplicate samples. The degradation testing of modified HA showed a higher weight loss compared with unmodified HA. In the case of ß-TCP the degradation rate was in similar level before and after modification. SEM images of materials showed visible changes in all of biomaterials surfaces. This changes may suggest the ability to form HA and osteoinductive properties of materials.
Źródło:
Engineering of Biomaterials; 2012, 15, no. 116-117 spec. iss.; 29-32
1429-7248
Pojawia się w:
Engineering of Biomaterials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of water stress on germination of yarrow populations (Achilleaspp.) from different bioclimatic zones in Iran
Autorzy:
Shanjani, Parvin Salehi
Izadpanah, Masoumeh
Mohamadpour, Mohamad Reza
Powiązania:
https://bibliotekanauki.pl/articles/2199733.pdf
Data publikacji:
2013-12-19
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
germination
polyethylene glycol
water potential
Yarrow
Opis:
The effects of water potential on germination were studied in 18 wild populations of three yarrow species (Achillea tenuifolia, A. vermicularis and A. filipendulina) from different bioclimatic zones in Iran. Water potential between 0 and -0.6 MPa were obtained using polyethylene glycol 6000 (PEG-6000) solutions. The study of water stress on germination showed that, regardless of the species and the populations, the lowering of the water potential reduced the capacity for germination and early seeding growth. These results indicated a strong genetic potential for drought tolerance during germination within each species. These differences in germination ability of wild populations of each species might be attributed to intraspecific variations resulting from the effects of natural selection and genetic pool background.
Źródło:
Plant Breeding and Seed Science; 2013, 68; 39-54
1429-3862
2083-599X
Pojawia się w:
Plant Breeding and Seed Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of cell membrane injury in caraway [Carum carvi L.] genotypes in water deficit conditions
Autorzy:
Seidler-Lozykowska, K
Bandurska, H.
Bocianowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/58454.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
cell membrane
caraway
Carum carvi
genotype
water deficit condition
polyethylene glycol
medicinal plant
Opis:
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.
Źródło:
Acta Societatis Botanicorum Poloniae; 2010, 79, 2; 95-99
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Formation, characterization, and analysis of curcumin nanoformulation for evaluating its in vitro cytotoxicity
Autorzy:
Parmar, Nilam
Mansuri, Abdulkhalik
Trivedi, Krupali
Ansari, Khairah
Kumar, Priyesh
Bagban, Mohammed Azim
Jhala, Devendrasinh
Patel, Alpesh
Chettiar, Shiva Shankaran
Powiązania:
https://bibliotekanauki.pl/articles/16706246.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
anticancer
curcumin nanoformulation
D-α-tocopheryl polyethylene glycol 1000 succinate
solubility
stability
Opis:
Nanotechnology holds significance in all fields of research, and the formation and surface alterations of nanomaterials are particularly important in this discipline. Nanoformulations synthesized with bioactive plant components play a crucial role in the improvement of several therapeutics and diagnostics. In the present study, we reported the synthesis of a curcumin nanoformulation (CN) by using curcumin and D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). The synthesized CN was characterized using dynamic light scattering, UV-Visible spectrophotometry, Fourier-transform infrared spectroscopy, field-emission scanning electron microscopy, and X-ray diffraction. Furthermore, it was evaluated for solubility, drug loading, encapsulation efficiency, stability, in vitro release, and anticancer potentials. The role of TPGS in the synthesis of CN was validated. The synthesized CN exhibited a size of 6.2 ± 1.9 nm, needle-shaped morphology, a polydispersity index of 0.164, and zeta potential of -10.1 ± 3.21 mV, as determined by characterization techniques. Its water solubility was 2.5 × 104 times higher than that of pure curcumin. The encapsulation efficiency and curcumin loading efficiency of the synthesized CN were found to be 80 and 10%, respectively, with storage stability exceeding 30 days. Moreover, the synthesized CN demonstrated significant in vitro anticancer activity against the colorectal cancer cell line HCT-116, with an IC50 value of 12.74 ± 0.54 μM at 24 h.
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2023, 104, 3; 275-287
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Encapsulation of L-ascorbic acid via polycaprolactone-polyethylene glycol-casein bioblends
Autorzy:
Ozsagiroglu, E.
Guvenilir, Y. A.
Powiązania:
https://bibliotekanauki.pl/articles/779951.pdf
Data publikacji:
2015
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
casein
drug encapsulation
L-ascorbic acid
polycaprolactone
polyethylene glycol
spray dryer
Opis:
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.
Źródło:
Polish Journal of Chemical Technology; 2015, 17, 4; 32-36
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Enhancement of Some Mechanical Properties of Polyethylene Glycol by Adding Carboxymethyl Cellulose as a Blends and Applied in Wood Glue
Autorzy:
Obeid, Karrar Abd-Ali
Al-Bermany, Abdul-Kareem J.
Habeeb, Majeed Ali
Powiązania:
https://bibliotekanauki.pl/articles/1193936.pdf
Data publikacji:
2015
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Acoustical Properties
CMC
Carboxymethyl Cellulose
PEG
Polyethylene Glycol
Ultrasonic Technique
Wood Glue
Opis:
The (PEG/CMC) blends were prepared by liquids mixing method, the appropriate concentrations of PEG were (0.1-0.2 to 0.8 g/mL)% are dissolved in (500 mL) of distilled water under stirring without heat for (20 min.) then added the CMC with two weights (0.25 and 0.5) g for each PEG concentrates at (288 K). In order to evaluate the mechanical properties of (PEG/CMC) blends the ultrasonic measurements were performed at these samples, these properties are ultrasonic velocity, compressibility, acoustic impedance and bulk modulus, were made at fixed frequency (f = 25 kHz), another acoustic mechanical properties were measured and calculated at a same time such as the ultrasonic wave amplitude absorption by using oscilloscope, then calculated the absorption coefficient and the transmittance ratio of the sound. It was found that there is significant relationship between ultrasonic velocity and material properties results show that adding PEG effects on the density then on the absorption of the ultrasonic waves inside the blend samples. Finally applied this blend in various concentrations as additive to imported wood glue and found that increasing the adhesion force after adding comparing with pure. FT-IR test has been made.
Źródło:
World Scientific News; 2015, 21; 12-23
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Characterization of Polyethylene Glycol Dinitrates
Autorzy:
Matyáš, R.
Šelešovský, J.
Jalový, Z.
Roháčová, J.
Powiązania:
https://bibliotekanauki.pl/articles/358415.pdf
Data publikacji:
2011
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
polyethylene glycol dinitrate
synthesis
properties
decomposition
kinetic decomposition
Opis:
Polyethylene glycol dinitrates (PEGN) with molecular weights between 400 and 20 000 gźmol-1 were prepared from polyethylene glycols by esterifcation with nitric acid/sulfuric acid in dichloromethane. The products were characterized by gel permeation chromatography. The yield of PEGN increases with increasing reaction temperature (0-40 °C) however large liberation of nitrogen oxides was observed at 40 °C. No infuence of reaction temperature (0-40 °C) on the cleavage of the polyethylene glycol chain during esterifcation was observed. The dependence of melting point on the molecular weight of PEGN was determined. Polyethylene glycol dinitrates with molecular weights Mn above 454 are not sensitive to impact. Heat of combustion of PEGN increases with increasing molecular weight. All samples tested decompose in a similar way during thermal exposition.
Źródło:
Central European Journal of Energetic Materials; 2011, 8, 3; 145-155
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ dodatku glikolu poli(etylenowego) na właściwości mas lejnych do wytwarzania form ceramicznych na osnowie SiC do zastosowań w odlewnictwie precyzyjnym części turbin lotniczych
Effect of polyethylene glycol addition on ceramic slurry properties used in investment casting
Autorzy:
Małek, M.
Wiśniewski, P.
Matysiak, H.
Sitek, R.
Kurzydłowski, K. J.
Powiązania:
https://bibliotekanauki.pl/articles/279094.pdf
Data publikacji:
2014
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Inżynierii Materiałów Polimerowych i Barwników
Tematy:
masa ceramiczna
odlewanie precyzyjne
glikol polietylenowy
forma odlewnicza
spoiwo
turbina lotnicza
ceramic slurry
investment casting
polyethylene glycol
shell mould
binder
aircraft turbine
Opis:
W artykule przedstawiono wyniki badań właściwości technologicznych mas ceramicznych na osnowie SiC mogących znaleźć zastosowanie do produkcji form odlewniczych do odlewania precyzyjnego części turbin lotniczych. Zawiesiny ceramiczne z SiC o stężeniu 65% otrzymano w mieszadle mechanicznym z dodatkiem 6, 10, 15% wag. glikolu poli(etylenowego) spełniającego rolę spoiwa oraz upłynniacza. Przeprowadzono szereg badań materiałoznawczych dla proszku, polimeru oraz wytworzonych mas lejnych, w tym lepkość względną i dynamiczną, pomiar gęstości, pH oraz zanurzeniowy test płyty mosiężnej. Pomiary prowadzono przez 96 h.
The presented paper relate the application of SiC in manufacturing shell moulds for investment casting of aircraft turbine elements. The tested shell moulds were produced through the „dip and stucco” method. Ceramic slurries with a SiC concentration of 65% wt. were applied. The polyethylene glycol was added at different ranges (6, 10, 15% wt.) as a binder and a flow agent. The characterization of SiC powder was done by Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) methods. Properties of ceramic slurries such as: relative and dynamic viscosity, density, pH and plate weight were studied using a range of techniques. The results shows that slurries based on SiC and polyethylene glycol meet the investment casting requirements of aircraft turbine parts and have very promising properties.
Źródło:
Przetwórstwo Tworzyw; 2014, [R.] 20, nr 1 (157), 1 (157); 40-49
1429-0472
Pojawia się w:
Przetwórstwo Tworzyw
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physiological adaptations to osmotic stress and characterization of a polyethylene glycol-responsive gene in Braya humilis
Autorzy:
Lirong, W.
Pengshan, Z.
Xin, Z.
Xiaopeng, W.
Xiaofei, M.
Yi, L.
Powiązania:
https://bibliotekanauki.pl/articles/58230.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
physiological adaptation
osmotic stress
polyethylene glycol
gene
Braya humilis
drought
expression pattern
Opis:
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.
Źródło:
Acta Societatis Botanicorum Poloniae; 2016, 85, 1
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of polyethylene glycol concentration on morphology of polypropylene membranes
Autorzy:
Lenart, P.
Kotra-Konicka, K.
Kalbarczyk, J.
Powiązania:
https://bibliotekanauki.pl/articles/115580.pdf
Data publikacji:
2014
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
membrane modification
polyethylene glycol
polypropylene membrane
modyfikacja membrany
glikol polietylenowy
błona polipropylenowa
Opis:
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.
Źródło:
Challenges of Modern Technology; 2014, 5, 2; 9-14
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena obiektów cebuli (Allium cepa L.) pod względem tolerancji na suszę w fazie kiełkowania i wzrostu siewek
Evaluation of onion (Allium cepa L.) accessions for drought tolerance at germination and seedling growth
Autorzy:
Kłosińska, Urszula
Powiązania:
https://bibliotekanauki.pl/articles/2199269.pdf
Data publikacji:
2020-12-09
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
Allium cepa
glikol polietylenowy (PEG)
niedobór wody
tolerancja
polyethylene glycol (PEG)
tolerance
water deficit
Opis:
Celem badań była ocena wpływu niedoboru wody na zdolność kiełkowania nasion i wzrost siewek cebuli oraz identyfikacja obiecujących obiektów do wykorzystania w przyszłych programach hodowli nowych odmian cebuli tolerancyjnych na stres suszy. Oceniono 150 linii/odmian cebuli pochodzących z polskich i zagranicznych firm hodowlano-nasiennych oraz z Banku Genów Instytutu Ogrodnictwa w Skierniewicach. Doświadczenia prowadzono w warunkach laboratoryjnych indukując stres suszy przez zastosowanie 18% poliglikolu etylenowego (PEG8000) w fazie kiełkowania nasion i 10% PEG w fazie siewek. Badane obiekty cebuli wykazały istotne zróżnicowanie pod względem tolerancji na stres suszy, potwierdzone wysokimi wartościami współczynnika zmienności (CV) dla ocenianych parametrów: maksymalny procent skiełkowanych nasion (35,3%), świeża masa siewek (38,5%), długość liścieni siewek (42,9%) i długość korzeni siewek (56,3%). Zanotowano, że niedobór wody najmniej ograniczył kiełkowanie nasion o 23%, następnie długość korzeni o 36%, a najbardziej świeżą masę siewek i długość liścieni, odpowiednio o 52% i 53,5%. Stwierdzono silną korelację (r = 0,81‒0,86) między cechami opisującymi wzrost siewek w warunkach suszy, wskazując, że deficyt wody redukuje wzrost całych siewek. Natomiast zależności pomiędzy nimi a kiełkowaniem w stresie suszy okazały się nieistotne (r = 0,19‒0,24). Spośród 150 obiektów cebuli, genotyp 171026 wykazał wysoki poziom tolerancji na suszę zarówno w fazie kiełkowania, jak i w fazie siewek.
The aim of this study was to assess the effect of water deficiency on germination ability and growth of onion seedlings, and identify promising accessions for use in future breeding programs of new onion varieties with drought tolerance. We evaluated 150 onion lines/cultivars derived from Polish and foreign breeding and seed companies and from the Gene Bank of the Institute of Horticulture in Skierniewice. Experiments were performed under laboratory conditions inducing drought stress by using 18% polyethylene glycol (PEG8000) in the seed germination phase and 10% PEG in the seedling phase. Significant differences in reaction to drought stress were observed among onion accessions, confirmed by the high values of the coefficient of variation (CV) for the assessed parameters: maximum percentage of seedling (56,3%). The received results showed, that water deficiency reduced seed germination the least by 23%, then the root length by 36%, and the fresh weight of seedling and cotyledon length by 52% and 53,5%, respectively. A high correlation (r = 0,81‒0,86) between the features describing the growth of seedlings under drought conditions was found, indicating that water deficit reduced growth of whole seedlings. However, no correlation (r = 0,19‒0,24) between them and germination under drought conditions was observed. Among 150 onion accessions, genotype 171026 showed a high level of drought tolerance, both in seed germination stage and in seedling growth stage.
Źródło:
Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin; 2020, 291; 93-99
0373-7837
2657-8913
Pojawia się w:
Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin
Dostawca treści:
Biblioteka Nauki
Artykuł

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