Current Science

Sushil Kumar ¹, Renu Kumari ²

Affiliations
1 SKA Institution for Research, Education and Development, 4/11 Sarv Priya Vihar, New Delhi 110 016, IN
2 National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110 067, IN

Abstract

Cultivation of Bt⁺ genotypes has dispensed with insecticidal sprays and thereby corn and cotton farmers have hugely benefited worldwide. Recent recordings of genetically diverse Cry-resistance in insect pests of Bt⁺ corn and cotton fields have raised grave concern. Curiously, bulk of Cry-resistant pink bollworms found in certain Bt⁺ cotton fields in India proved homozygous for multiple linked mutations. Besides, dominantly inheritable Cry-resistance and cross resistance between different Cry-proteins have also been noted. To stem evolution of resistance against antiinsect protein-toxins, new nematology research on IPM procedures, complementary to refuge and Cry stacking technologies is imminently needed.

Keywords

Bt Corn and Cotton, Complementary Pestmanagement Practices, Cry-Resistant Variants, Insect Pests.

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Aditya Kharya ¹, H. K. Sachan ¹, Sameer K. Tiwari ¹, Saurabh Singhal ¹, P. Chandra Singh ¹, Santosh Rai ¹, Sushil Kumar ¹, Manish Mehta ¹, P. K. R. Gautam ¹

Affiliations
1 Wadia Institute of Himalayan Geology, Dehra Dun 248 001, IN

Abstract

We report here the occurrence of albitite in Nubra valley of Ladakh region in the Trans-Himalaya area within Indian Territory at 344446N and 77338E before Panamik (in the Wish Pond, local name of the area). The albitite has been characterized by petrography, mineral chemistry, X-ray diffraction and whole rock geochemistry (i.e. major, trace and rare earth elements (REE)). The albitite comprises 85-96% albite and amphibole, whereas apatite, zircon and ilmenite occur as accessory minerals. The textural relationship and geochemical data indicate its igneous origin. The albitite contains about 5-6 ppm U and Th which may possibly host U-REE mineralization.

Keywords

Albitite, Karakoram, Mineral Chemistry, XRD, Whole Rock Chemistry.

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Sushil Kumar ¹, D. K. Aswal ¹

Affiliations
1 CSIR-National Physical Laboratory, Dr K.S. Krishnan Marg, New Delhi 110 012, IN

Abstract

In India, the research on solar cells is being pursued in various scientific laboratories and industries; however, there is no facility for the validation of solar cell efficiency. Globally there are three recognized centers available for validation of solar cell efficiency, namely National Renewable Energy Laboratory (USA), Fraunhofer Physikalisch-Technische Bundesanstalt (Germany) and Institute of Advanced Industrial Science and Technology (Japan). In order to validate the efficiency of the fabricated solar cells, these have to be sent to one of the above-mentioned centers and this process is not only expensive but also time consuming.

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M. Shanmugam ¹, S. V. Vadawale ¹, Arpit R. Patel ¹, Hitesh Kumar Adalaja ¹, N. P. S. Mithun ¹, Tinkal Ladiya ¹, Shiv Kumar Goyal ¹, Neeraj K. Tiwari ¹, Nishant Singh ¹, Sushil Kumar ¹, Deepak Kumar Painkra ¹, Y. B. Acharya ¹, Anil Bhardwaj ¹, A. K. Hait ², A. Patinge ², Abinandhan Kapoor ³, H. N. Suresh Kumar ³, Neeraj Satya ³, Gaurav Saxena ⁴, Kalpana Arvind ⁴

Affiliations
1 Physical Research Laboratory, Ahmedabad 380 009, IN
2 Space Applications Centre, Ahmedabad 380 015, IN
3 U. R. Rao Satellite Centre, Bengaluru 560 017, IN
4 Laboratory for Electro Optics Systems, Bengaluru 560 058, IN

Abstract

Solar X-ray Monitor (XSM) is one of the scientific instruments onboard Chandrayaan-2 orbiter. The XSM along with instrument CLASS (Chandra’s Large Area soft X-ray Spectrometer) comprise the remote X-ray fluorescence spectroscopy experiment of Chandrayaan- 2 mission with an objective to determine the elemental composition of the lunar surface on a global scale. XSM instrument will measure the solar X-rays in the energy range of 1–15 keV using state-of-the-art silicon drift detector. The flight model of the XSM payload has been designed, realized and characterized for various operating parameters. XSM provides energy resolution of ~180 eV at 5.9 keV with high time cadence of one second. The X-ray spectra of the Sun observed with XSM will also contribute to the study of solar corona. The detailed description and the performance characteristics of the XSM instrument are presented in this article.

Keywords

Lunar X-Rays, Silicon Drift Detector, Solar X-Rays, X-Ray Spectrometer.

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M. Shanmugam ¹, S. V. Vadawale ¹, Arpit R. Patel ¹, N. P. S. Mithun ¹, Hitesh Kumar Adalaja ¹, Tinkal Ladiya ¹, Shiv Kumar Goyal ¹, Neeraj K. Tiwari ¹, Nishant Singh ¹, Sushil Kumar ¹, Deepak Kumar Painkra ¹, A. K. Hait ², A. Patinge ², Abhishek Kumar ³, Saleem Basha ³, Vivek R. Subramanian ³, R. G. Venkatesh ³, D. B. Prashant ³, Sonal Navle ³, Y. B. Acharya ¹, S. V. S. Murty ¹, Anil Bhardwaj ¹

Affiliations
1 Physical Research Laboratory, Ahmedabad 380 009, IN
2 Space Applications Centre, Ahmedabad 380 015, IN
3 U.R. Rao Satellite Centre, Bengaluru 560 017, IN

Abstract

Alpha Particle X-ray Spectrometer (APXS) is one of the two scientific experiments on Chandrayaan-2 rover named as Pragyan. The primary scientific objective of APXS is to determine the elemental composition of the lunar surface in the surrounding regions of the landing site. This will be achieved by employing the technique of X-ray fluorescence (XRF) spectroscopy using in situ excitation source ²⁴⁴Cm emitting both X-rays and alpha particles. These radiations excite characteristic X-rays of the elements by the processes of particle induced X-ray emission and XRF. The characteristic X-rays are detected by the ‘state-of-the-art’ X-ray detector known as Silicon Drift Detector, which provides high energy resolution, as well as high efficiency in the energy range of 1–25 keV. This enables APXS to detect all major rock forming elements such as, Na, Mg, Al, Si, Ca, Ti and Fe. The flight model of the APXS payload has been completed and tested for various instrument parameters. The APXS provides energy resolution of ~135 eV at 5. 9keV for the detector operating temperature of about –35°C. The design details and the performance measurement of APXS are presented in this paper.

Keywords

Alpha Particle X-Ray Spectrometer, CSPA, Silicon Drift Detector, X-Ray Spectrometer.

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