Wyniki wyszukiwania - BazTech

1

Wybrane problemy materiałowe stwierdzane w pokryciach papowych dachów płaskich

Francke Barbara, Koda Eugeniusz

Materiały Budowlane

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2024

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nr 6

47--50

2

Applications of modal analysis for examining structural state of synthethic-fibre nonwoven composites

Nossol P., Gliniorz R., Kroll L., Heinrich M.

Composites Theory and Practice

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2015

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R. 15, nr 3

130--136

EN

The dynamic behaviour of thermoplastic samples reinforced with aramid or polyester based nonwoven fabrics has been investigated. Changes in the structural state of specimens through open hole and impact damage could be proved by changes in modal parameters. Furthermore a directionality study has been performed showing clear dependence of modal parameters and fibre orientation. An appropriate frequency band was selected for a robust structural state detection of the samples. Additionally, a special modal hammer device was used to increase the accuracy of determining the modal parameters. This work continues investigations which can serve as a foundation for modal analysis based structural health monitoring (SHM) and quality control systems for composite structures.

PL

Zbadane zostało dynamiczne zachowanie próbek kompozytowych o osnowie termoplastycznej, wzmocnionych włókniną aramidową lub poliestrową. Wykazano, że zmiany w stanie struktury próbek, wywołane wierceniem otworów i uszkodzeniem udarowym, mogą być wykrywane w oparciu o zmiany parametrów modalnych. Przeprowadzono również badania, w których pokazano wyraźną zależność pomiędzy parametrami modalnymi a ukierunkowaniem włókien. Do właściwego wykrywania stanu strukturalnego próbek wybrane zostało odpowiednie pasmo częstotliwości. Dodatkowo zastosowane zostało specjalne urządzenie dla młotka modalnego zwiększające dokładność wyznaczania parametrów modalnych. Praca jest kontynuacją badań, które mogą służyć jako podstawa dla systemu przeznaczonego do monitorowania stanu konstrukcji oraz kontroli jakości, bazującego na analizie modalnej.

3

Moisture/sorption characteristics of starch-filled poly (styrene-co-butyl acrylate) latex based composites reinforced with polyester nonwoven fabric

Satheesh Kumar M. N., Siddaramaiah

Autex Research Journal

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2007

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Vol. 7, no. 2

111--118

EN

Poly (styrene-co-butyl acrylate) latex was prepared with a 70:30 weight ratio of styrene to butyl acrylate. The prepared latex was incorporated with various weight percentages of cornstarch. The cornstarch-filled copolymer latex was used as a matrix to fabricate the polyester nonwoven fabric reinforced composites. The pickup ratio of latex to fabric was maintained at 3.2:1. The moisture sorption characteristics of composites were examined at 270C for water activity (aw) from 0.1 to 0.9. The sorption data was used to fit six different sorption isotherm models proposed in the literature. The model constants were determined by linear fitting of the sorption equations. The ranges of applicability of water activity for the isotherm models reported in the article lies between 0.1 and 0.4 (monomolecular layer) for the Braunauer-Emmet-Teller (BET) model, and between 0.3 and 0.9 (multimolecular and capillary condensation layers) for other models. The value of the coefficient of determination (R2 = 0.97±0.02) confirms the linear fitting of the equations studied.

4

Studies on corn starch filled poly (styrene-co-butyl acrylate) latex reinforced polyester nonwoven fabric composites

Satheesh Kumar M. N., Siddaramaiah

Autex Research Journal

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2005

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Vol. 5, no. 4

228--235

EN

Poly (styrene-co-butyl acrylate) latex was prepared with a 70:30 weight ratio of styrene to butyl acrylate. Various weight percentages of cornstarch were incorporated into the prepared copolymer latex. Polyester nonwoven fabric reinforced-cornstarch-filled copolymer latex composites were manufactured by the impregnation method. The pickup ratio of latex to fabric was maintained at 3.2:1. The composites' physico-mechanical properties, percent water absorption and percent thickness swelling were studied. The manufactured cornstarch-filled composites were evaluated for their ability to retain their shape after being moulded to the desired shape by measuring the percentage area, shape retention, hardness and resilience. It was observed that the manufactured thermoplastic composite specimens retained or increased their mechanical properties up to 20 wt% cornstarch loading.

5

Zastosowanie inteligentnej techniki odpylania w Krośnieńskich Hutach Szkła.

Schneider H.E., Sawicki P., Krężałek A.

Szkło i Ceramika

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1999

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R. 50, nr 3

31-36