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Rao, A. S.
- Fern-Allies and Ferns of Kameng District, Arunachal Pradesh
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Indian Forester, Vol 106, No 5 (1980), Pagination: 327-349Abstract
The richness of the Pteridophytic flora of Kameng District, Arunachal Pradesh is emphasised, with an enumeration of 22 species of Fern-allies in 3 genera and 3 families; 214 species of Ferns in 71 genera, and 21 families.
- Cyperus sulcinux C. B. Clarke. A New Record from Kumaon Himalaya
Abstract Views :371 |
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Indian Forester, Vol 106, No 10 (1980), Pagination: 703-703Abstract
Cyperus sulcinux C.B.CI., a genarally wide-spread species, but rare and confined to small pockets within this range of distribution, and hitherte unknown from the Kumaon Himalaya, is here recorded for the first time and briefly described.- Paphiopedium fairieanum (Lindl) Pfitz.-Habitat, Descriptive and Cultural Notes
Abstract Views :271 |
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Indian Forester, Vol 103, No 1 (1977), Pagination: 29-32Abstract
Paphiopedilum fairieannum (Lindl.) pritz., an elegant lady-slipper orchid, from Kameng district, Arunachal Pradesh, has been described with note on its natural habitat and culture. Suggestions on its conservation have also been given.- Goodyera macrantha Maxim-from Kameng District, Arunachal Pradesh
Abstract Views :256 |
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Indian Forester, Vol 102, No 3 (1976), Pagination: 197-199Abstract
Goodyera macrantha Maxim, a small ground orchid hitherto known to occur from Japan, is now found at Bomdila in Kameng district of Arunachal Pradesh. The orchid is described, including analytical illustrations.- Utrigulilriil pubesgens Sm.-first Report of its Occurrence in India
Abstract Views :200 |
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Source
Indian Forester, Vol 93, No 1 (1967), Pagination: 32-32Abstract
no abstract- Mitrastemon yalanotoi (Makino) Makino (Rafelesiaceaf)-a Unique Root Parasite New to the Indian Flora
Abstract Views :265 |
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Source
Indian Forester, Vol 98, No 4 (1972), Pagination: 234-235Abstract
Mitrastemon yamamotoi (Makino) Makino, a unique ischolar_main parasite hitherto known to occur from Japan to Thailand and Sumatra with a related species In Mexico, is now found in India, at Mawsmal near Cherrapunji in the Khasi&Jalntia Hills of Meghalaya. The parasite is described, Including photographs, analytical illustrations and some related notes.- Petrography and Geochemistry of the Sandstones of Murree Group Around Laren, Udhampur, Jammu Himalaya
Abstract Views :171 |
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Authors
Affiliations
1 Post Graduate Department of Geology, Jammu University, Jammu, IN
1 Post Graduate Department of Geology, Jammu University, Jammu, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 36, No 5 (1990), Pagination: 502-511Abstract
The importance of the sandstones of Murree Group is becoming more and more due to the possibilities of occurrence of hydrocarbons. It is evident from the petrographic and geochemical studies that these sandstones are of sublitharenite type. Probably low to medium grade metamorphic, intermediate to acid igneous and preexisting sedimentary rocks were sources for these rocks. A cratonic near-shore depositional environment is suggested for these sediments. The palaeoclimatic conditions were mild as indicated by their mineralogy.Keywords
Petrology (Sedimentary), Geochemistry, Sandstone, Murree Group, Jammu, Kashmir Himalaya.- An Account of the Flowering Plants of Indore District in Madhya Pradesh
Abstract Views :194 |
PDF Views:111
Authors
A. S. Rao
1,
A. R. Sastry
1
Affiliations
1 Botanical Survey of India, Eastern Circle, Shillong, IN
1 Botanical Survey of India, Eastern Circle, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 6, No 2-4 (1964), Pagination: 267-286Abstract
This account of the flowering plants of Indore district is based on the observations made during 1961, 1962 and 1963. The enumeration includes 566 species 373 genera and 94 famalies of the flowering plants. The nomenclature has been revised to conform to modern taxonomic usage in accordance with the Montreal Code.Full Text
- A Contribution towards a Flora of Biligirirangan Hills, Mysore State
Abstract Views :172 |
PDF Views:149
Authors
Affiliations
1 Botanical Survey of India, Calcutta, IN
2 Botanical Survey of India, Shillong, IN
3 Botanical Survey of India, Poona, IN
1 Botanical Survey of India, Calcutta, IN
2 Botanical Survey of India, Shillong, IN
3 Botanical Survey of India, Poona, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 9, No 1-4 (1967), Pagination: 206-234Abstract
Biligirirangan hills in Mysore State are somewhat isolated from the other hill ranges in the Western ghats, and the Nilgiris. This sketch of the vegetation is based on detailed collections made by the authors as well as the collections made some 28 years ago by Barnes. The enumeration includes 825 species of vascular plants under 484 genera and 133 families.Full Text
- Rhynchoglossum lazulinum - A New Species of Gesneriaceae
Abstract Views :152 |
PDF Views:130
Authors
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 9, No 1-4 (1967), Pagination: 280-282Abstract
No Abstract.Full Text
- Bulbophyllum brachypodum Nom. Nov. with Two New Varieties
Abstract Views :158 |
PDF Views:128
Authors
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 10, No 3-4 (1968), Pagination: 350-352Abstract
Cirrhopetalum brevipes is transferred to Bulbophyllum under the name of B. brachypadum. Further two new varieties, var. geei and var. parviflorum are described from Kameng District, and Bhutan in Eastern Himalayas respectively.Full Text
- Gonatanthus Klotzsch in Khasi and Jaintia Hills, Assam
Abstract Views :164 |
PDF Views:121
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 10, No 3-4 (1968), Pagination: 353-357Abstract
The genus Gonatanthus Klotz. including only two species, both occurring in K. & J. Hills, has been discussed after a detailed study of live plants and herbarium specimens. Apart from descriptions, and documentation of specimens, notes on variations and confusions in literature, are added, including a de novo description of the hitherto unknown spadix of G. ornatus Schott. The two species are illustrated with analytical drawings.Full Text
- Curcumorpha - A New Genus of Zingiberaceae
Abstract Views :197 |
PDF Views:175
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 13, No 3-4 (1971), Pagination: 339-341Abstract
No Abstract.Full Text
- Notes on Zingiberaceae from Assam
Abstract Views :203 |
PDF Views:147
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 11, No 3-4 (1969), Pagination: 245-248Abstract
These notes based on a study of live plants and related herbarium material include the description of the hitherto unknown vegetative phase of Amomum pauciflorum Baker; distribution of Amomum corynostachyum Wall.; detail description of Hornstedtia loroglossa (Gagnep.) Schum. and additional remarks on Globba clarkei Baker. Kaempferia involucrata King ex Baker and Mantisia saltatoria Sims.Full Text
- Notes on Hedychium Koenig, Including Four New Species from Khasi & Jaintia Hills, Assam
Abstract Views :214 |
PDF Views:99
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 11, No 1-2 (1969), Pagination: 120-128Abstract
Four new species of Hedychium Koenig: H. calcaratum, H. dekianum, H. gracillimum and H. rubrum are described from K.&J. Hills, Assam with analytical illustrations. Critical additional descriptive notes are also included in respect of a few other species.Full Text
- Materials towards a Monocot Flora of Assam-II. (Zingiberaceae & Marantaceae)
Abstract Views :199 |
PDF Views:138
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
1 Botanical Survey of India, Dehra Dun, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 14, No 1-4 (1972), Pagination: 114-143Abstract
The families Zingiberaceae and Marantaceae in the above series are presented in this paper.Full Text
- Materials towards a Monocot Flora of Assam (Hydrocharitaceae & Burmanniaceae)
Abstract Views :206 |
PDF Views:131
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 12, No 1-4 (1970), Pagination: 139-143Abstract
Preliminary taxonomic studies on 2 (two) families of the Monocotyledons of Assam (Hydrocharitaceae and Burmanniaceae) are presented here. These studies will form the materials for a Monocot flora of Assam.Full Text
- Contributions to the Botany of North Lakhimpur Subdivision, Assam
Abstract Views :157 |
PDF Views:148
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 11, No 3-4 (1969), Pagination: 403-413Abstract
An account of the vegetation with an enumeration of 604 species of vascular plants from North Lakhimpur subdivision in Upper Assam, based on a fortnight’s collection of the junior author in May, 1966, and 3 previous collections by others. The account emphasises the aquatic vegetation of the area.Full Text
- Arisaema setosum-A New Species of Araceae from Siang District, N.E.F.A.
Abstract Views :317 |
PDF Views:107
Authors
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 11, No 1-2 (1969), Pagination: 196-197Abstract
No Abstract.Full Text
- Thrixspermum muscaeflorum A. S. Rao & J. Joseph-A New Orchid Species from K. & J. Hills, Assam
Abstract Views :166 |
PDF Views:87
Authors
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 11, No 1-2 (1969), Pagination: 204-205Abstract
No Abstract.Full Text
- Parakaempferia synantha (Zingiberaceae)-A New Genus & Species from Assam
Abstract Views :182 |
PDF Views:94
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 11, No 1-2 (1969), Pagination: 206-208Abstract
No Abstract.Full Text
- Two New Adventives to the Shillong Flora
Abstract Views :130 |
PDF Views:108
Authors
A. S. Rao
1,
G. K. Deka
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 12, No 1-4 (1970), Pagination: 263-264Abstract
No Abstract.Full Text
- Zeylanidium olivaceum (Gardn.) Engl. (Podostemaceae) - First Report of its Presence in Kameng District, Arunachal Pradesh
Abstract Views :166 |
PDF Views:115
Authors
A. S. Rao
1,
P. K. Hajra
1
Affiliations
1 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 12, No 1-4 (1970), Pagination: 271-272Abstract
No Abstract.Full Text
- Galeola altissima (BL.) Reichb. F. First Report of its Occurrence in India, from North Cachar Hills, Assam
Abstract Views :180 |
PDF Views:107
Authors
A. S. Rao
1,
N. C. Deori
2
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 15, No 1-2 (1973), Pagination: 123-125Abstract
No Abstract.Full Text
- Materials towards a Monocot Flora of Assam-III. (Taccaceae, Dioscoreaceae & Stemonaceae)
Abstract Views :202 |
PDF Views:124
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
1 Botanical Survey of India, Dehra Dun, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 15, No 3-4 (1973), Pagination: 189-203Abstract
In continuation with the previous publications in the Bulletin, preliminary taxonomic studies on three more families of the Monocotyledons of Assam region (Taccaceae, Dioscoreaceae and Stemonaceae) are presented here.Full Text
- Sebaea Khasiana C. B. Cl.-A Little Known Gentianaceae Herb from Kameng District, Arunachal Pradesh
Abstract Views :151 |
PDF Views:130
Authors
A. S. Rao
1,
P. K. Hajra
2
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 15, No 1-2 (1973), Pagination: 145-146Abstract
No Abstract.Full Text
- Ariopsis peltata Nimmo, First Report of a Poorly Known Aroid, from Kameng Dist., Arunachal Pradesh, India
Abstract Views :318 |
PDF Views:152
Authors
A. S. Rao
1,
P. K. Hajra
2
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 15, No 1-2 (1973), Pagination: 171-173Abstract
No Abstract.Full Text
- Materials towards a Monocot Flora of Assam-IV (Pontederiaceae, Xyridaceae & Commelinaceae)
Abstract Views :197 |
PDF Views:137
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
1 Botanical Survey of India, Dehra Dun, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 16, No 1-4 (1974), Pagination: 1-20Abstract
In continuation to the previous publications on the Monocot Flora of Assam, this paper deals with the families Pontederiaceae, Xyridaceae and Commelinaceae.Full Text
- Eulophia Mannii Hook. F.-a Scarcely Known Ground Orchid from Assam
Abstract Views :169 |
PDF Views:124
Authors
A. S. Rao
1,
P. K. Hajra
2
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
2 Bobanical Survey of India, Shillong, IN
1 Botanical Survey of India, Dehra Dun, IN
2 Bobanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 16, No 1-4 (1974), Pagination: 156-157Abstract
No Abstract.Full Text
- Materials towards a Monocot Flora of Assam-V
Abstract Views :237 |
PDF Views:138
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Howrah, IN
1 Botanical Survey of India, Howrah, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 18, No 1-4 (1976), Pagination: 1-48Abstract
Further to earlier contributions in previous issues of this Bulletin, twelve more families of the monocotyledons of Assam: Flagellariaceae, Juncaceae, Typhaceae, Sparganiaceae, Araceae, Lemnaceae, Triuridaceae, Alismataceae, Butomaceae, Aponogetonaceae, Potamogetonaceae and Eriocaulaceae are presented here. The account includes keys to identification, description, distribution and notes for 36 Genera and 106 Species, as Materials towards a Monocot Flora of Assam.Full Text
- Hedychium Radiatum & H. robustum (Zingiberaceae)-Two New Species from Kameng District, Arunachal Pradesh
Abstract Views :162 |
PDF Views:127
Authors
A. S. Rao
1,
P. K. Hajra
2
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 16, No 1-4 (1974), Pagination: 163-166Abstract
No Abstract.Full Text
- Ensete glaucum (Roxb.) Cheesm. in the Khasi Hills, Meghalaya, India
Abstract Views :198 |
PDF Views:156
Authors
A. S. Rao
1,
P. K. Hajra
1
Affiliations
1 Botanical Survey of India, Howrah, IN
1 Botanical Survey of India, Howrah, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 18, No 1-4 (1976), Pagination: 207-210Abstract
No Abstract.Full Text
- Polypleurum Wallichii (R. Br. Ex Griff.) Warming and Zeylanidium Lichenoids (Kurz) Engler-Two Interesting Podostemaceae from Meghalaya
Abstract Views :126 |
PDF Views:94
Authors
A. S. Rao
1,
P. K. Hajra
2
Affiliations
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
1 Botanical Survey of India, Dehra Dun, IN
2 Botanical Survey of India, Shillong, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 17, No 1-4 (1975), Pagination: 207-209Abstract
No Abstract.Full Text
- Floristic Studies in North-Eastern India (Old Assam Region)
Abstract Views :181 |
PDF Views:146
Authors
Affiliations
1 Botanical Survey of India, Howrah, IN
1 Botanical Survey of India, Howrah, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 19, No 1-4 (1977), Pagination: 56-60Abstract
No Abstract.Full Text
- Notes on Cyperaceae of Assam
Abstract Views :218 |
PDF Views:122
Authors
A. S. Rao
1,
D. M. Verma
1
Affiliations
1 Botanical Survey of India, Calcutta, IN
1 Botanical Survey of India, Calcutta, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 22, No 1-4 (1980), Pagination: 80-90Abstract
The paper includes, as addition to the Indian flora, Carex eteusinoides Turcz. ex Kunth, Fimbristylis fimbristyloides (F. v. Muell.) Druce and F. yunnanensis Glrake. Six species have been recorded as new to the Assam region. On examination of mature specimens, Carex fuscifructus Clarke has been proved to be a distinct species. Mistakes have been pointed out on the reported occurrence in India of Carex lachenalii Schkuhr, C. prainii Clarke and Juncellus stylosus Clarke. Doubts have been raised on the distinctivity of several taxa, and biosystematic studies have been suggested to solve some of the complexes. A list of twelve species and one variety endemic to the Assam region, and miscellaneous notes on some other taxa have also been included.Full Text
- The Annual Science Farce
Abstract Views :253 |
PDF Views:92
Authors
Source
Current Science, Vol 108, No 4 (2015), Pagination: 474-475Abstract
No Abstract.Full Text
- Why not all Research Data be on Open Access?
Abstract Views :272 |
PDF Views:90
Authors
Affiliations
1 Mangalore Biotech Laboratory, Mangalore 575 002, IN
2 Department of Biotechnology and Genetic Engineering, Bharathidasan University, Tiruchirappalli 620 024, IN
1 Mangalore Biotech Laboratory, Mangalore 575 002, IN
2 Department of Biotechnology and Genetic Engineering, Bharathidasan University, Tiruchirappalli 620 024, IN
Source
Current Science, Vol 107, No 7 (2014), Pagination: 1093-1093Abstract
No Abstract.Full Text
- Evaluating Scientists and 'Impact Factor'
Abstract Views :261 |
PDF Views:85
Authors
Affiliations
1 Mangalore Biotech Laboratory, Mangalore 575 002, IN
2 Bharathidasan University, Tiruchirappalli 620 024, IN
1 Mangalore Biotech Laboratory, Mangalore 575 002, IN
2 Bharathidasan University, Tiruchirappalli 620 024, IN
Source
Current Science, Vol 107, No 9 (2014), Pagination: 1367-1367Abstract
No Abstract.Full Text
- Make in India – Some Suggestions
Abstract Views :294 |
PDF Views:79
Authors
Affiliations
1 Department of Biotechnology, Bharathidasan University, Tiruchirappalli 620 024, IN
1 Department of Biotechnology, Bharathidasan University, Tiruchirappalli 620 024, IN
Source
Current Science, Vol 110, No 1 (2016), Pagination: 9-9Abstract
No Abstract.Full Text
- Rao Versus Murthy Debate
Abstract Views :275 |
PDF Views:86
Authors
Affiliations
1 Mangalore Biotechnology Laboratory, Mangalore 575 002, IN
2 Department of Biotechnology, Bharathidasan University, Tiruchirappalli 620 024, IN
1 Mangalore Biotechnology Laboratory, Mangalore 575 002, IN
2 Department of Biotechnology, Bharathidasan University, Tiruchirappalli 620 024, IN
Source
Current Science, Vol 109, No 8 (2015), Pagination: 1377-1377Abstract
No Abstract.Full Text
- DBT/MST Should Fund Prudently
Abstract Views :252 |
PDF Views:72
Authors
Affiliations
1 Department of Biotechnology, Bharathidasan University, Tiruchirappalli 620 024, IN
1 Department of Biotechnology, Bharathidasan University, Tiruchirappalli 620 024, IN
Source
Current Science, Vol 110, No 12 (2016), Pagination: 2210-2210Abstract
The National Biotechnology Development strategy is exciting indeed. The ambition is to turn Indian biotechnology into a 100 billion US dollars industry by 2025. However, how much money DBT/MST is going to invest is not mentioned. Is it really possible to achieve this ambition - within just another 9 years?.Full Text
- Detection of Solar Cycle Signal in the Tropospheric Temperature using COSMIC Data
Abstract Views :228 |
PDF Views:76
Authors
Affiliations
1 Radio and Atmospheric Physics Lab, Rajdhani College, University of Delhi, Delhi 110 015, IN
2 Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital 263 002, IN
3 Department of Applied Physics, Delhi Technical University, Delhi 110 042, IN
4 Department of Geophysics, Kyoto University, Kyoto 606850, IN
1 Radio and Atmospheric Physics Lab, Rajdhani College, University of Delhi, Delhi 110 015, IN
2 Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital 263 002, IN
3 Department of Applied Physics, Delhi Technical University, Delhi 110 042, IN
4 Department of Geophysics, Kyoto University, Kyoto 606850, IN
Source
Current Science, Vol 115, No 12 (2018), Pagination: 2232-2239Abstract
Influence of the solar cycle on temperature structure is examined using radio occultation measurements by COSMIC/FORMASAT-3 satellite. Observations from January 2007 to December 2015 comprising 3,764,728 occultations, which are uniformly spread over land and sea, have been used to study temperature changes mainly in the troposphere along with the solar cycle over 60°N–60°S geographic latitudes. It was a challenging task to identify the height at which the solar cycle signal could be observed in temperature perturbations as different atmospheric processes contribute towards temperature variability. Using a high spatial resolution dataset from COSMIC we are able to detect solar cycle signal in the zonal mean temperature profiles near surface at 2 km and upward. A consistent rise in the interannual variation of temperature was observed along with the solar cycle. The change in the temperature structure showed a latitudinal variation from southern to northern hemisphere over the period 2007–2015 with a significant positive influence of sunspot numbers in the solar cycle. It can be concluded that the solar cycle induces changes in temperature by as much as 1.5°C. However, solar cycle signal in the stratospheric region could not be identified as the region is dominated by large-scale dynamical motions like quasi-biennial oscillation which suppress the influence of solar signal on temperature perturbations due to its quasi-periodic nature.Keywords
Radio Occultation, Solar Cycle, Sunspot Number, Tropospheric Temperature.Full Text
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- Remote Sensing for the Detection of Bio- and Non-Bioaerosols for Defence Applications
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Authors
Affiliations
1 Laser Science and Technology Centre, Defence Research and Development Organization, Delhi 110 054, IN
2 Department of Applied Physics, Delhi Technological University, Delhi 110 042, IN
1 Laser Science and Technology Centre, Defence Research and Development Organization, Delhi 110 054, IN
2 Department of Applied Physics, Delhi Technological University, Delhi 110 042, IN
Source
Current Science, Vol 118, No 12 (2020), Pagination: 1980-1983Abstract
The present study describes a novel approach to distinguish between bio- and fluorescing non-bioparticles from a stand-off distance of 5 m using laser-induced fluorescence technique. The variations of peak fluorescence intensities of bio- and non-bioaerosols with time were observed experimentally. Substantial decay of fluorescence peak intensities with time was observed in case of bioparticles, while it was negligible in case of non-bioparticles. This difference in decay of fluorescence peaks with time can form the basis for making a distinction between bio- and fluorescing non-bioparticles from stand-off distance. Further, this approach can be converted to a handy product for defence and security applications.Keywords
Bio and Non-Bio Agents, Laser Induced Fluorescence, Laser Spectroscopy, UV Radiation Effect.Full Text
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