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1

Receding contact between an orthotropic layer and an orthotropic half-space

100%

Chaudhuri P. , Ray S.

Archives of Mechanics

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1998

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tom Vol. 50, nr 4

743-755

EN

The problem of smooth receding contact between an orthotropic layer and an orthotropic half-space has been considered in this papaer. The paper includes a generalization of the results of the paper by L. M. Keer, J. Dundurs, K. C. Tsai concerning receding contact betwee an isotropic layer and an isotropic half-space. It is observed that the task of finding the extent of contact in the loaded configuration can be reduced to an eigenvalue problem of a homogenous Fredholm integral equation. The kernel of the Fredholm integral equation is found to be dependent on the elastic constans of the layer but is independent of the elastic constans of the half-space below, which is in contrast to the study for the isotropic materials, where the kernel is independent of the elastic constans. Finally some numerical results have been presented in graphs in order to compare the results of interest for isotropic and orthotropic materials.

2

An investigation of gamma-radiation sensitivity on in vitro study of Hordeum vulgare L.

80%

Chaudhuri P. , Sengupta R. K. , Ghosh P. D.

Acta Societatis Botanicorum Poloniae

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1995

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tom 64

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nr 2

163-164

3

Assessment of morphological damages of leaves of selected plant species due to vehicular air pollution, Kolkata, India

70%

Nandy A. , Talapatra S. N. , Bhattacharjee P. , Chaudhuri P. , Mukhopadhyay A.

International Letters of Natural Sciences

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2014

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tom 04

EN

The present study deals to know morphological damages of leaves of four selected plant species near roadside due to vehicular air pollution in Kolkata, India. The selected plant species are Ficus bengalensis, Ficus religiosa, Alstonia scholaris and Neolamarckia cadamba as these are very common as avenue trees. The study area was selected as per Low vehicular load (LVL) as control area, moderate vehicular load (MVL) area, high vehicular load (HVL) area and heavy vehicular load (HeVL) These three sampling stations were selected on the basis of moderate, high and heavy traffic density and continuous vehicular movement as per visualization. The control area was considered as time dependent vehicular movement due to less traffic density. The morphological damages with special reference to length (L), breadth (B) and L/B ratio and visible injuries in leaves. The visible injuries such as pigmentation, chlorosis, necrosis and burning of leaves of four selected species is documented. There was an increasing and decreasing tends in all four plant species at all three vehicular emission exposed sites (MVL, HVL and HeVL) compared to control site (LVL). In all experimental sites such as MVL, HVL and HeVL, the extra growth and reduction pattern significantly (P < 0.001, 0.01 or 0.05) observed when compared to control site (LVL) for L, B and L/B ratio. The visible injuries (in %) of leaves were also observed in increasing trends. This study is a preliminary assessment of tolerant species that already have been used in greenbelt development to protect air pollutants as well as biological monitoring to know exact load of automobile air pollution but further researches are needed in relation to biochemical and genetic damage study. It was observed that out of four selected species Ficus bengalensis, Alstonia scholaris and Neolamarckia cadamba are more tolerant species and Ficus religiosa is a less tolerant species because of these may have fighting abilities by waxy coatings, accumulation and degradation abilities to vehicular air pollution at all exposed area when compared to control area.

4

Assessment of viable fungi in indoor air: a case study from Tagore’s residence at Jorasanko, India

61%

Bhattacharyya S. , Mukherjee D. , Sarkar P. , Ghosh S. , Samaddar B. , Chaudhuri P.

International Letters of Natural Sciences

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2015

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tom 06

EN

Indoor environment is significant with respect to human health especially if it is concerned when the building is v. Aim of very old. In the present study was to assess the presence of airborne fungi at an old building in Kolkata India where lots of tourists are exposed every day. Residence of famous Nobel laureate poet Rabindranath Tagore (built in the 18th century and presently used as a famous museum) in Kolkata, West Bengal was selected for this study and the indoor fungi from different room of the museum were assessed by using exposure plate technique. Humidity, temperature, wind speed and illuminance were also measured by hygrometer, thermometer anemometer and lux-meter respectively. The fungal species isolated from the air samples of different rooms were Aspergillus sp., Penicillium sp., Paecilomyces sp., Trichoderma sp, Alternaria sp Verticillium sp, Fusarium sp, Cladosporium sp, Yeast, Curvularia sp. and Helminthosporium sp. among them, Aspergillus sp. (71.4% at monsoon at library), Penicillium sp (57% at summer at library), Paecilomyces sp.(91% at monsoon at manuscript room) are mostly dominated pathogens, which may harm the workers and visitors of the museum. No significant correlation among colony forming unit of fungi with illuminance, wind speed and temperature in the tested indoor environment was noted whereas, the humidity in indoor environment played a crucial (P<0.05) role. Round the year humidity control may be required for maintaining healthy environment.