Informatics Publishing Limited

P. B. Meshram , K. C. Joshi , A. K. Sarkar

Abstract

Eleven selected clones of teak, Tectona grandis belong to Andhra Pradesh, Mabarashtra, Orissa, Tamil Nadu and Uttar Pradesh were evaluated for their natural variation in suspectibility to teak leaf skeletonizer, Eutectona machaeralis Walk. APT-20, APT-8 and MHSCJ-2 were observed to be the most resistant clones as the leaf areas consumed by the larvae were 1.07, 2.13 and 3.94 cm². Whereas UPD-1 followed by TNT-11 were the most suspectible (leaf area fed being 9.46 and 6.87 cm²).

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A. K. Sarkar ¹, N. Datta ¹, U. Chatterjee ¹

Affiliations
1 Botanical Survey of India, Howrah, IN

Abstract

No Abstract.

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A. K. Sarkar ¹, N. Datta ¹, U. Chatterjee ¹

Affiliations
1 Botanical Survey of India, Howrah, IN

Abstract

No Abstract.

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Sobhan K. R. Mukherjee ¹, A. K. Sarkar ¹

Affiliations
1 Department of Botany, University of Kalyani, Kalyani, W.B., IN

Abstract

A comparative study of morphology and anatomy of mature cypselas in 14 species belonging to 10 genera, such as BIDENS, CHRYSANTHELLUM, COREOPSIS, COSMOS, ECHINACEA, GAILLARDIA, GLOSSOGYNE, HELIANTHUS, TITHONIA and XANTHIUM under the tribe Heliantheae (Asteraceae) was undertaken under light and scanning electron microscopes. Morphologically the form and structure of cypselas, carpopodia and pappus are diacritical for characterization of taxa. In all species pericarp is well differentiated into 2 zones. Cells of the epicarp are usually tangentially elongated, provided with yellow or brown substances. Mesocarp is mainly differentiated into 4 zones. Number and distribution of vascular traces, phytomelan layer and secretory cavities are taxonomically significant in certain taxa. An artificial bxonomic key using the detailed morphological, anatomical and SEM observations on the mature cypselas are provided.

Keywords

Asteraceae, Heliantheae, Morphology, Anatomy of Cypselas.

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K. K. Pant ¹, Vinit Kumar ¹, Bhaskar Biswas ¹, Arvind Kumar ¹, Shankar Lal ¹, Sona Chandran ¹, Saket Kumar Gupta ¹, Md. Khursheed ², Pravin Nerpagar ¹, A. K. Sarkar ¹, Ravi Kumar Pandit ¹, K. Ruwali ³, K. Sreeramulu ³, S. Das ³, R. S. Shinde ³, S. Chouksey ⁴, J. K. Parate ⁴, Viraj Bhanage ⁵, P. P. Deshpande ⁵, Shradha Tiwari ⁵, Mandar Joshi ⁶, Lalita Jain ⁵, Anand Valecha ⁷, Ayukt Pathak ⁵, M. A. Ali ⁵, H. R. Bundel ⁵, Purushottam Shrivastava ⁸, T. Reghu ⁸, Umesh Kale ⁸, Yashwant Wanmode ⁸, Praveen Mohania ⁸, Jaikishan Mulchandani ⁸, Akhil Patel ⁸, Mahesh Acharya ⁸, Ashish Mahawar ⁸, Mahendra Lad ⁹, M. K. Jain ⁹, Nitesh Tiwari ⁹, Pritam S. Bagduwal ⁹, V. G. Sathe ¹⁰, Sujata Joshi ¹⁰, Ram Shiroman ¹⁰, A. S. Yadav ¹⁰, Randhir Kumar ¹⁰, Alok Singh ¹¹, Vineet K. Dwivedi ¹¹, Mangesh Borage ¹², S. R. Tiwari ¹¹

Affiliations
1 Materials and Advanced Accelerator Sciences Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
2 Advanced Lasers and Optics Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
3 Accelerator Magnet Technology Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
4 Design and Manufacturing Technology Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
5 Laser Controls and Instrumentation Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
6 Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Mumbai 400 085, IN
7 Accelerator Control Systems Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
8 Pulsed High Power Microwave Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
9 Radio Frequency Systems Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
10 Ultra-High Vacuum Technology Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
11 Power Converters Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN
12 Homi Bhabha National Institute, Raja Ramanna Centre for Advanced Technology, Indore 452 013, IN

Abstract

An Infrared Free Electron Laser (IR-FEL) designed to operate in the 12.5–50 μm wavelength band is presently in an advanced stage of commissioning at the Raja Ramanna Centre for Advanced Technology (RRCAT), Indore. Here we report results from first experiments on the IR-FEL after installation of its optical cavity, which has resulted in a power output that is ~105 times the expected spontaneous emission power for the beam parameters used in the experiment. The estimated out-coupled peak micro-pulse power during these experiments is ~2 kW. This is the first observed signature of lasing in the IR-FEL, and the first reported lasing in a FEL in India. This communication discusses the development of the IR-FEL, the recent experimental results, and the ongoing efforts to further increase the IR power to the design peak out-coupled power of 2 MW.

Keywords

Beam Parameters, Free Electron Laser, Infrared Power, Undulator.

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A. K. Sarkar ¹

Affiliations
1 Acme Electro Industries Private Limited, Calcutta, IN

Abstract

Though efforts are made in the design to maintain the field as uniform as may be, in Engineering works quite often it happens that due to manufacturing difficulties, special limitations & many other factors, the non-uniformity of field creeps in. The peculiarity of the non-uniform field is the occurrence of corona prior to break-down. As corona is known to cause a considerable damage to the insulation system & break-down causes complete damage of the system, the high voltage Engineers face the troubles due to the occurrence of corona & break-down in the operation & maintenance of any high voltage equipment or system. As corona occurs only in non uniform field, the study of non-uniform field assumes importance both from corona & breakdown point of view. In the present discussion use is made of a needle-plane gap, since a needle-plane arrangement gives highly divergent field.

In the following discussions, efforts have been made to explain the mechanism responsible for corona formation in non-uniform field & also the consequences which lead to its break-down have been pointed out.

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A. K. Sarkar ¹, D. Hazra ¹

Affiliations
1 Botanical Survey of India, Howrah, IN

Abstract

Cytological investigations on 7 taxa of the tribe Helianthoideae (Asteraceae) reveal certain interesting features. Meiotic counts reported here are all normal, forming regular bivalents. Karyotypes show homogeneity with graded types of chromosome complement. The occurrence of tetraploid species of Tridax procumbens L. (n = 18) is of interest. The reports of Eclipta alba (L.) Hassk. (n = 11, 2n = 22), Tathonia tagetiflora Desf. ex Juss. (n=17), Xanthium strumarium L. (n = 18) are confirmatory nature. Aneuploid variations are also noted in some cases.

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