Informatics Publishing Limited

P. R. Golani ¹, D. Bhattacharyya ², S. Sanyal ², I. R. Kirmani ², G. Malhotra ², S. Bhattacharyya ², A. K. Grover ², J. L. Narang ²

Affiliations
1 Geological Survey of India, A.M.S.E. Wing, Central Zone, Seminary Hills, Nagpur - 440 006, IN
2 Geological Survey of India, Western Region, 15-16, Jhalana Dungri, Jaipur - 302 004, IN

Abstract

The Deldar-Kui-Chitrasani (DKC) fault is a brittle structure manifested by anastomosing system of fractures in the southwestern part of the South Delhi Fold Belt (SDFB). Based on the identification of cross-fibre and 'jigsaw puzzle' type structures, presence of vugs lined with cryptocrystalline quartz, replacement of calcite by chalcedonic quartz and evidences of argillic alteration, the breccia along the fault is recognised by present workers as epithermal breccia. Lithogeochemical sampling of the breccia reveals that, besides moderate base metal signatures, gold values are consistently present in significant concentrations comparable to regional anomalies associated with epithermal gold deposits in the United States. In view of the high proportion of magmatic rocks in the southwestern part of the SDFB, the DKC fault zone is considered a favourable target for searching epithermal type of gold mineralisation.

Keywords

Economic Geology, Epithermal Breccia, Lithogeochemistry, Gold Anomaly, Faults, Shear Zone, South Delhi Fold Belt, Rajasthan, Gujarat.

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G. Chandra ¹, S. Bhattacharyya ², S. Ray ³, L. K. Ghosh ¹, B. K. Gupta ¹

Affiliations
1 Dept. of Pharmaceutical Technology, Jadavpur University, Kolkata-700 032, IN
2 Oxford College of Pharmacy, 6/9, 1st Cross, Begur Road, Hongasandra, Bangalore-560 068, IN
3 Krupanidhi College of Pharmacy, #12/1, Chikkabellandur, Carmelram Post, Bangalore-560 035, IN

Abstract

This work aims at designing and evaluating a Extended release dosage form of Diazepam using Alginate- Eudragit RS 30D as the matrix-forming polymer employing the Ionotropic Gelation technique of micropellletization. The product was characterized by physicochemical parameters such as yield, drug entrapment efficiency, particle size, surface topography, granulometric study, loose surface crystal study, drug-excipient compatibility and in vitro release. The controlled release profile was optimized using a factorial design for achieving the correct blend of microparticles that closely matches the target release profile. The study illustrates the utility and advantage of designed experimentation in controlled drug delivery research.

Keywords

Diazepam, Extended Release, Micropellets, Factorial Design, Optimization

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Arpan Deyasi ¹, S. Bhattacharyya ²

Affiliations
1 Dept. of Electronics and Communication Engineering, RCC Institute of Information Technology, Kolkata-700015, IN
2 Dept. of Electronics and Communication Engineering, Greater Kolkata College of Engineering and Management, 24 Parganas (S)–743387, IN

Abstract

Penetration depth of boron in phosphorous-doped silicon for p⁺nn⁺ SDR type IMPATT structure is experimentally investigated by Secondary Ion Mass Spectrometry (SIMS) technique, and also validated using Scanning Electron Microscopy (SEM) instrument in this work. Spatial distribution of the impurity profile for the dopants and also of the constituent atoms is experimentally investigated to evaluate the near-accurate length of junction depth, which is well supported by the SEM measurement also. The measurement clearly gives a pictorial representation of the variation of atoms inside the device. Operating frequency of the device is directly dependent on junction depth, and hence its accurate evaluation carries significant role in designing the device. Two-step diffusion mechanism is considered for fabrication of the device, and impurity profile is numerically solved from Fick's law. Theoretical and experimental data have a very close resemblance which speaks about the accuracy of the investigation. Temperature and orientation dependence of diffusivity is also computed for near accurate estimation. Results are very important for design and fabrication of SDR IMPATT device for microwave performance.

Keywords

Diffusion, SEM, SIMS, Junction Depth.

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P. K. Jana , S. Bhattacharyya

Abstract

The paper presents yearly and seasonal variations of total column ozone densities at Kodaikanal (10°13' N, 77°28' E), an equatorial station, Srinagar (34°04' N, 74°49' E), a tropical station and Halley Bay (76°S, 27°W), a British Antarctic survey station from 1988 to 2005. Yearly mean ozone values decreased gradually at all these stations with different rates from 1988 to 2005. Ozone density attained maximum during July at Kodaikanal and January to March at Srinagar and Halley Bay, whereas, minimum during January and October, respectively. Oscillatory nature of ozone variation with 10.7 cm solar flux indicates comparable contribution of solar parameter and chemical processes on ozone depletion.

Keywords

Antarctic Ozone, Equatorial Ozone, Ozone Depletion, Relative Sunspot Number, Tropical Ozone

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K. K. Yadav ¹, N. Chouhan ², R. Thubstan ², S. Norlha ², J. Hariharan ², C. Borwankar ², P. Chandra ², V. K. Dhar ¹, N. Mankuzhyil ², S. Godambe ², M. Sharma ², K. Venugopal ², K. K. Singh ¹, N. Bhatt ², S. Bhattacharyya ¹, K. Chanchalani ², M. P. Das ², B. Ghosal ², S. Godiyal ², M. Khurana ², S. V. Kotwal ², M. K. Koul ², N. Kumar ², C. P. Kushwaha ², K. Nand ², A. Pathania ², S. Sahayanathan ¹, D. Sarkar ², A. Tolamati ², R. Koul ³, R. C. Rannot ⁴, A. K. Tickoo ⁵, V. R. Chitnis ⁶, A. Behere ⁷, S. Padmini ⁷, A. Manna ⁷, S. Joy ⁷, P. M. Nair ⁷, K. P. Jha ⁷, S. Moitra ⁷, S. Neema ⁷, S. Srivastava ⁷, M. Punna ⁷, S. Mohanan ⁷, S. S. Sikder ⁷, A. Jain ⁷, S. Banerjee ⁷, Krati ⁷, J. Deshpande ⁷, V. Sanadhya ⁸, G. Andrew ⁸, M. B. Patil ⁸, V. K. Goyal ⁸, N. Gupta ⁸, H. Balakrishna ⁸, A. Agrawal ⁸, S. P. Srivastava ⁹, K. N. Karn ⁹, P. I. Hadgali ⁹, S. Bhatt ⁹, V. K. Mishra ⁹, P. K. Biswas ⁹, R. K Gupta ⁹, A. Kumar ⁹, S. G. Thul ⁹, R. Kalmady ¹⁰, D. D. Sonvane ¹⁰, V. Kumar ¹⁰, U. K. Gaur ¹⁰, J. Chattopadhyay ¹¹, S. K. Gupta ¹¹, A. R. Kiran ¹¹, Y. Parulekar ¹¹, M. K. Agrawal ¹¹, R. M. Parmar ¹¹, G. R. Reddy ¹², Y. S. Mayya ¹³, C. K. Pithawa ¹⁴

Affiliations
1 Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085, India; Homi Bhabha National Institute, Mumbai 400 085, India, IN
2 Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
3 Formerly at Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
4 Raja Ramanna Fellow at Astrophysical Sciences Division, Mumbai 400 085, India, IN
5 Deceased, IN
6 Department of High Energy Physics, Tata Institute of Fundamental Research, Mumbai 400 005, India, IN
7 Electronics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
8 Control and Instrumentation Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
9 Center for Design and Manufacture, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
10 Computer Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
11 Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
12 Formerly at Reactor Safety Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
13 Formerly at Reactor Control Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN
14 Formerly at Electronics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India, IN

Abstract

The MACE telescope has recently been commissioned at Hanle, Ladakh, India. It had its first light in April 2021 with a successful detection of very high energy gamma-ray photons from the standard candle Crab Nebula. Equipped with a large light collector of 21 m diameter and situated at an altitude of ~4.3 km amsl, the MACE telescope is expected to explore the mysteries of the non-thermal Universe in the energy range above 20 GeV with very high sensitivity. It can also play an important role in carrying out multi-messenger astronomy in India.

Keywords

Gamma-ray astronomy, high energy radiative processes, non-thermal Universe, telescope.

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