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Influence of UV radiation on the color of furfurylated wood protected with refining coatings

100%

Jaglowski K., Marchwicka M.

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

|

2023

|

tom 121

2

Chemical modification: a non-toxic approach to wood preservation

88%

Rowell R. M.

Drewno. Prace Naukowe. Doniesienia. Komunikaty

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2005

|

tom 48

|

nr 173

3

Bending creep of Maritime pine wood (Pinus pinaster Ait.) chemically modified

75%

Lopes D. B., Mai C., Militz H.

Folia Forestalia Polonica. Series A . Forestry

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2013

|

tom 55

|

nr 3

The long-term performance of a structural member is determined by its durability and deformation with time. The bending creep behaviour of modified wood was assessed experimentally over a period of 35 days (840 hours). Four chemical modification processes were used: 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU), mmethylated melamine formaldehyde resin (MMF), tetraethoxysilane (TEOS) and amid wax (WA). Wood stakes with 20.10.200 mm RTL dimensions of Portuguese Maritime pine (Pinus pinaster Ait.) from sapwood part of the stem were used for evaluated the primary creep. Experiments were conducted at bending stresses amounting to 0.1, 0.2, 0.4 of the mean immediate wood bending strength obtained at equilibrium moisture content (EMC). Applying the same stress level (SL, 0.2), wood creep was also determined at the constant low and high moisture content. As results: Between low and medium SL (8 and 16 N/mm2), unmodified wood at indoors conditions did not show any effect in the creep factors (kc). However, at high SL (35 N/mm2) a slight increase (not significant) in the kc was found. It seems that the kc was nearly independent of the SL. In the lumen fill modification (TEOS and wax), the deposited material has not affected the creep behaviour under various SL. The cell wall modification (with DMDHEU and MMF resins) did not show any differences in the kc for low and medium SL (8 and 16 N/mm2). However, resin modification under high SL (35 N/mm2) has shown a significant reduction related to unmodified wood. Between both types of resin (DMDHEU and MMF) and levels of modification (WPG), significant effect was not found. At saturated conditions, lumen fill modification (TEOS and wax) did not show any effect on creep. In the cell wall modification (DMDHEU and MMF resin), significant reduction was recorded due to the embrittlement effect imparted by the modification (deposit of resin in the cell wall).

4

The influence of chemical modification on the CO2plus ion sorption process by anaerobic sludge

75%

Fristak V., Valovciakova M., Pipiska M., Lesny J.

Polish Journal of Environmental Studies

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2014

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tom 23

|

nr 3

Modification by chemical agents affected the sorption capacities of sludge from municipal wastewater treatment plants (WWTPs). We tried to characterize changes in sorption capacity of dried anaerobic sludge (DANS) after chemical modification by formaldehyde, methanol, and hydrochloric acid. Modified sludges were characterized by FT-IR spectroscopy, cation exchange capacity, and electrothermal atomic absorption spectrometry (ETAAS) analysis. Maximum sorption capacities Qmax at pH 6.0 for Co²⁺ ions calculated from Langmuir isotherm model were 175±5 μmol/g for unmodified DANS, 170±2 μmol/g for CH₂O-modified DANS, 12±0.2 μmol/g for CH₃OH-modified DANS, and 15±0.3 μmol/g for HCl-modified DANS. Our paper established the crucial role of carboxyl functional groups against amino and hydroxyl groups in sorption process of cobalt ions.

5

Analytical characterization of chemically modified starches by FT-Raman spectroscopy

75%

Phillips D. L., Xing J., Kong Chong C., Corke H.

Żywność Nauka Technologia Jakość. Suplement

|

2000

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tom 07

|

nr 2

We have recently developed an FT-Raman spectroscopic method for measuring the amount of chemical modification of starch samples from a diverse range of botanical sources and amylose contents. In this paper, we present results and FT-Raman spectroscopic calibration curves that can be used to measure the degree of chemical modification for starches that have been acetylated, succinylated, cationic modified, and maleic acid modified. The FT-Raman methodology we have developed is much faster than currently used wet chemistry techniques, is nondestructive of the sample, needs almost no sample preparation, does not require use of hazardous chemicals, and can be further developed for use as a quality control method for process control in manufacturing.

6

Characterisation of barley starches and their modified preparations

75%

Fortuna T., Juszczak L., Tobiasz E.

Polish Journal of Food and Nutrition Sciences

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2001

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tom 10

|

nr 2

Native barley starch and its waxy variety were subjected to chemical modification (esterification with sodium trimetylphosphate) and physical modification (heating at 200°C or microwave radiation). Unmodified starches and their preparations were examined in respect of the phosphorus rand amylose content, reduction and swelling capacities, water solubility, and pasting characteristics. On a basis of the results obtained it was found І that there were differences in some physico-chemical properties between native starch and waxy starch and that the modifications applied caused f further changes in these properties.

7

Molecular and chemical engineering of bacteriophages for potential medical applications

63%

Hodyra K., Dabrowska K.

Archivum Immunologiae et Therapiae Experimentalis

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2015

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tom 63

|

nr 2

8

The economical and ecological aspects of using the modified water-glass

63%

Izdebska-Szanda I.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

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2012

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tom 12

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nr 2

9

Chemiczna modyfikacja jako sposob nietoksycznej ochrony drewna

63%

Rowell R. M.

Biuletyn Informacyjny Ośrodka Badawczo-Rozwojowego Przemysłu Płyt Drewnopochodnych w Czarnej Wodzie

|

2004

|

tom 44

|

nr 3-4

142-148

10

Air oxidation of potato starch over zinc (II) catalyst

63%

Gumul D., Gambus H., Gibinski M.

Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology

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2005

|

tom 08

|

nr 4

11

The effect of chemical modification of wood veneer surfaces on their bondability

63%

Tymyk D., Bekhta P., Sedliacik J.

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

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2013

|

tom 81

12

Effect of acylation and enzymatic modification on pea proteins allergenicity

63%

Szymkiewicz A., Jedrychowski L.

Polish Journal of Food and Nutrition Sciences

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2008

|

tom 58

|

nr 3

In the study chemical modifications (acetylation or succinylation) and enzymatic hydrolysis (with Alcalase) were applied in order to reduce the allergenicity of particular pea proteins. Application of Alcalase after acylation lowered the immunoreactive properties of pea vicilin from 14-17% down to 2-2.5% as compared to that of the native fraction. Under these conditions, the immunoreactivity of legumin and albumins was reduced by nearly 100%. Proteolysis of pea proteins under conditions optimal for Alcalase decreased the immunoreactivity of vicilin to about 24%. Application of acetic anhydrides for further modification led to lowering their level to 6% and 9%, during acetylation and succinylation, respectively. The immunoreactivity of pea legumin and albumins was reduced down to 1-3%. The lower immunoreactive properties of particular pea proteins do not correspond with lower allergenicity of total proteins. Of all the applied methods acetylation of previously hydrolysed proteins proved to be the most effective; it resulted in about 70% allergenicity decrease (on the average) of thus modified samples as compared to native pea proteins. Yet, the reaction showed an individual character and may be different in individual patients.

13

Interactions of annexins IV and VI with erythrocyte membrane in the presence of Ca2. A biochemical and electron microscopy study

63%

Bandorowicz-Pikula J., Sobota A.

Cellular and Molecular Biology Letters

|

1996

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tom 01

|

nr 1

Annexins IV and VI were found to interact with human erythrocyte membrane in a calcium-dependent manner. Chemical and enzymatic modification of the membrane constituents pointed to phosphatidylserine as a target membrane molecule responsible for the interaction of the annexin/Ca complexes with the membrane. The membrane-associated annexins were shown to form clusters reflecting, perhaps, the presence of PS microdomains in a lateral plane of membrane.

14

Chemical modification of lysine and arginine residues of bovine heart 2-oxoglutarate dehydrogenase: Effect on the enzyme activity and regulation

63%

Ostrovtsova S. A.

Acta Biochimica Polonica

|

1998

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tom 45

|

nr 4

Chemical modification of arginine and lysine residues of bovine heart 2-oxoglutarate dehydrogenase with phenylglyoxal and pyridoxal 5'-phosphate inactivated the enzyme, indicating the importance of these residues for the catalysis. Inactivation caused by pyridoxal 5'-phosphate was prevented in the presence of thiamine pyrophosphate and Mg2+ allowing the assumption that lysine residues participate in binding of the cofactor.

15

Enzymatic, physical and chemical modifications of krill chitin

63%

Wojtasz-Pajak A., Kolodziejska I., Debogorska A., Malesa-Ciecwierz M.

Bulletin of the Sea Fisheries Institute

|

1998

|

nr 1

16

Rozwój technologii acetylacji drewna

51%

Biuletyn Informacyjny Ośrodka Badawczo-Rozwojowego Przemysłu Płyt Drewnopochodnych w Czarnej Wodzie

|

2019

|

tom 60

|

nr 1-2

17

Wlasciwosci preparatow skrobi ziemniaczanej kleikowanej z dodatkiem zelaza

51%

Zdybel E., Leszczynski W.

Zeszyty Problemowe Postępów Nauk Rolniczych

|

2006

|

tom 511

|

nr 2

639-652

The properties of preparations of potato starch glueying with various amounts of iron(III) were studied. The methodology of preparing specimens was chosen in order to simultaneous applicaton of both, the chemical and physical factors. Potato starch was glueying by adding adequately 0.1; 1.0; 4.2 g iron per 100 g of starch. Starch saturated with iron citrate was also glueying. Obtained glues were exposed to physical factors: mixing, freezing or both. Afterwards they were dried and crumbled. Following properties of the received preparations were determined: water holding capacity, solubility, viscosity of 1% glues, heat of phase transition and the of fraction resistant to amyloglucosidase and α-amylase activity. Preparations of the starch saturated with iron and next glueying were characterized by higher water holding capacity, solubility and viscosity of 1% gel, whereas the preparations of the starch glueying with addition of iron showed also higher water holding capacity, solubility, but less viscosity of 1% gel in comparison to the preparations obtained from natural glueying starch. Freezing caused lowering of solubility at 80°C and an increase of the heat of phase transition. The starch preparations glueying with addition of 1 and 4.2 g iron‧100 g⁻¹, showed the decreased susceptibility to amylolytic enzymes.

18

Comparison of the stability of buttery aroma in gels prepared with maize or potato starch

51%

Bortnowska G.

Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology

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2009

|

tom 12

|

nr 3

19

Detection of DNA methylation in eucaryotic cells

51%

Sulewska A., Niklinska W., Kozlowski M., Minarowski L., Niklinski J., Dabrowska K., Chyczewski L.

Folia Histochemica et Cytobiologica

|

2007

|

tom 45

|

nr 4

315-324

20

Temperatura przejścia szklistego i krytyczne parametry przechowywania skrobi ziemniaczanej i jej pochodnych

51%

Witczak T.

Żywność Nauka Technologia Jakość

|

2017

|

tom 24

|

nr 2

Celem niniejszej pracy była ocena wpływu utleniania, acetylacji oraz podwójnej modyfikacji (acetylacji i utleniania) na temperaturę przejścia szklistego (Tg) i krytyczne parametry przechowywania skrobi ziemniaczanej. Utlenianie skrobi prowadzono z zastosowaniem chloranu(I) sodu, natomiast acetylację – z wykorzystaniem bezwodnika kwasu octowego. Próbki o różnej aktywności wody (aw) uzyskano metodą statyczno-eksykatorową po umieszczeniu wysuszonej skrobi i jej modyfikatów w środowisku o różnej wilgotności. Temperaturę przejścia szklistego wyznaczono przy użyciu skaningowej kalorymetrii różnicowej. Wszystkie modyfikacje prowadziły do zmiany wartości temperatury przejścia szklistego w stosunku do skrobi natywnej, przy czym najbardziej do niej zbliżona była skrobia utleniona. Zależność temperatury przejścia szklistego od równowagowej zawartości wilgoci opisano równaniem Gordona-Taylora i zmodyfikowanym równaniem Couchman-Karasz. Temperatura przejścia szklistego bezwodnego biopolimeru (Tgs) zmieniała się w zakresie 241,5 ÷ 306,8 ºC w zależności od rodzaju skrobi oraz przyjętej temperatury odniesienia (temperatury przejścia szklistego wody – Tgw). Wartość Tg wszystkich próbek zmniejszała się ze wzrostem aktywności wody. Uzyskane wartości stałej k modelu Gordona-Taylora zawierały się w granicach 4,94 ÷ 6,86, a zmiana pojemności cieplnej skrobi Δ Cps, wyznaczona z modelu Couchman-Karasz – w zakresie 0,283 ÷ 0,393 J⋅g⁻¹⋅K⁻¹. Zmiana krytycznych parametrów przechowywania (aktywność wody i temperatura przejścia szklistego) wskazuje na wzrost trwałości uzyskanych preparatów. Za najbardziej trwałą uznano skrobię acetylowaną.

Ograniczanie wyników

Influence of UV radiation on the color of furfurylated wood protected with refining coatings

Chemical modification: a non-toxic approach to wood preservation

Bending creep of Maritime pine wood (Pinus pinaster Ait.) chemically modified

The influence of chemical modification on the CO2plus ion sorption process by anaerobic sludge

Analytical characterization of chemically modified starches by FT-Raman spectroscopy

Characterisation of barley starches and their modified preparations

Molecular and chemical engineering of bacteriophages for potential medical applications

The economical and ecological aspects of using the modified water-glass

Chemiczna modyfikacja jako sposob nietoksycznej ochrony drewna

Air oxidation of potato starch over zinc (II) catalyst

The effect of chemical modification of wood veneer surfaces on their bondability

Effect of acylation and enzymatic modification on pea proteins allergenicity

Interactions of annexins IV and VI with erythrocyte membrane in the presence of Ca2. A biochemical and electron microscopy study

Chemical modification of lysine and arginine residues of bovine heart 2-oxoglutarate dehydrogenase: Effect on the enzyme activity and regulation

Enzymatic, physical and chemical modifications of krill chitin

Rozwój technologii acetylacji drewna

Wlasciwosci preparatow skrobi ziemniaczanej kleikowanej z dodatkiem zelaza

Comparison of the stability of buttery aroma in gels prepared with maize or potato starch

Detection of DNA methylation in eucaryotic cells

Temperatura przejścia szklistego i krytyczne parametry przechowywania skrobi ziemniaczanej i jej pochodnych