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Basu, S. K.
- The Damodar, Bengal's River of Sorrow
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Indian Forester, Vol 69, No 12 (1943), Pagination: 469-470Abstract
No abstract
- Anti-Erosion Work in Kalimpong Forest Division
Abstract Views :190 |
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Indian Forester, Vol 73, No 1 (1947), Pagination: 11-14Abstract
No abstract- Kimberlites, Lamproites and Lamprophyres of India: A Petrographic Atlas
Abstract Views :179 |
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Authors
Affiliations
1 Geological Survey of India, AMSE Wing, Vasudha Bhavan, Kumaraswamy Layout, Bangalore - 560 078, IN
1 Geological Survey of India, AMSE Wing, Vasudha Bhavan, Kumaraswamy Layout, Bangalore - 560 078, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 69, No Spl Iss 3 (2007), Pagination: 467-504Abstract
A pictorial display of some of the kimberlites, lamproites and lamprophyres of India, is given in this work. This would give an idea about the texture and mineralogy of these rocks from different cratonic regions of the Indian shield.Keywords
Kimberlites, Lamproites, Lamprophyres, Petrography, Atlas.- Bul-Bil Shoots in Arenga Engleri Becc
Abstract Views :131 |
PDF Views:104
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 17, No 1-4 (1975), Pagination: 189-192Abstract
No Abstract.Full Text
- Observations on Two 'Threatened Arecoid Palms of Nicobar Islands Cultivated at the Indian Botanic Garden, Howrah
Abstract Views :180 |
PDF Views:115
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 26, No 3-4 (1984), Pagination: 207-210Abstract
No Abstract.Full Text
- Nomenclatural Notes on Leucostegia Yaklaensis Bedd. Nom. Illeg. (Pterldophyta)
Abstract Views :185 |
PDF Views:123
Authors
G. Panigrahi
1,
S. K. Basu
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 27, No 1-4 (1985), Pagination: 113-115Abstract
Leucostegia yaklaensis Bedd. (1892) is established, under Art. 7.11 and Art. 63.1, as an illegitimate name for Athyrium andersoni (C. B. Clarke) Panigr. et S. K. Basu [Asplenium ander-sonii C. B. Clarke (1876)]. Typification of both the taxa is discussed and C. B. Clarke 27426 from Tonglo (K) is selected as the lectotype of Asplenium andersonii C. B. Clarke.Full Text
- Epidermal Studies in Eophylls (Juvenile Leaves) of some Arecoid Palms
Abstract Views :185 |
PDF Views:157
Authors
S. K. Basu
1,
Saibal Basu
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 20, No 1-4 (1978), Pagination: 124-132Abstract
The eophylls in palms are morphologically very consistent for each palm group and they show remarkable distinguishing characters. Epidermal studies on the eophylls of 'Sixteen Arecoid palms show that in all, five different types of epidermal complexes can be recognised within the group and this information is of taxonomic importance.Full Text
- Nathaniel Wallich's Collection of Pteridophytes in Central National Herbarium (CAL)
Abstract Views :250 |
PDF Views:135
Authors
S. K. Basu
1,
Sova Rudra
1
Affiliations
1 Botanical Survey of India, Cryptogamic Section, Howrah 711 103, IN
1 Botanical Survey of India, Cryptogamic Section, Howrah 711 103, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 50, No 1-4 (2008), Pagination: 23-38Abstract
In the present paper 267 sheets of Pteridophytes in Wallich's collection at CAL have been enumerated with the names as they appear in Wallich's numerical list, the names under which these specimens were cited in Beddomes work and present status of these species.Full Text
- On the Occurrence of Three Species of Pseudocylosorus Airy Shaw from West Bengal
Abstract Views :154 |
PDF Views:111
Authors
Anjali Biswas
1,
S. K. Basu
1
Affiliations
1 Botanical Survey of India, Cryptogamic Unit, Howrah 711 103, IN
1 Botanical Survey of India, Cryptogamic Unit, Howrah 711 103, IN
Source
Nelumbo - The Bulletin of the Botanical Survey of India, Vol 50, No 1-4 (2008), Pagination: 190-192Abstract
No Abstract.Full Text
- Measuring Ecosystem Patterns and Processes through Fractals
Abstract Views :326 |
PDF Views:102
Authors
Affiliations
1 Department of Computer Science, Banaras Hindu University, Varanasi 221 005, IN
2 Department of Botany, Banaras Hindu University, Varanasi 221 005, IN
3 Forestry and Ecology Department, Indian Institute of Remote Sensing, Dehradun 248 001, IN
1 Department of Computer Science, Banaras Hindu University, Varanasi 221 005, IN
2 Department of Botany, Banaras Hindu University, Varanasi 221 005, IN
3 Forestry and Ecology Department, Indian Institute of Remote Sensing, Dehradun 248 001, IN
Source
Current Science, Vol 109, No 8 (2015), Pagination: 1418-1426Abstract
Changes in ecosystems are highly complex, heterogeneous and are extremely difficult to measure through single scale. Fractal geometry has been used to quantitatively estimate the extent of irregularity in ecosystem changes. However, in some cases it has been overly used giving misleading results. To avoid this, other metrics are also being used in studying changes in forest ecosystems. In this article, we review use of fractal geometry in measuring ecosystem components in a range of ecological conditions. Further, case studies from forest fragmentation and soil aggregates stability in different Indian tropical ecosystems with respect to management practices and environmental change have been described using fractal dimension. We have tried to point out some instances where fractals can more appropriately be used in assessing ecosystems properties and where it could not be successfully used. Characterization of ecological situations where fractals can effectively be used in general remains an important issue.Keywords
Ecosystem Complexity, Ecosystem Patterns, Fractal Dimension, Landscape Change, Soil Processes.Full Text
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- Petrogenetic Model for Evolution of Alkaline-Carbonatite Complex along Tamar-Porapahar Shear Zone in North Singhbhum Proterozoic Mobile Belt, Eastern India and its Metallogenic Aspects
Abstract Views :177 |
PDF Views:171
Authors
Affiliations
1 PPOD, AMSE Wing, Geological Survey of India, Eshwar Nagar, Bangalore - 560 070, IN
1 PPOD, AMSE Wing, Geological Survey of India, Eshwar Nagar, Bangalore - 560 070, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 62, No 2 (2003), Pagination: 250-252Abstract
No Abstract.Full Text
- Proterozoic Rock Suites along South Purulia Shear Zone, Eastern India: Evidence for Rift-Related Setting
Abstract Views :326 |
PDF Views:3
Authors
Affiliations
1 Geological Survey of India, 27 Jawaharlal Nehru Road, Kolkata - 700 016, IN
2 Geological Survey of India, Op WB-SK-AN, Eastern Region, DK-6, Salt Lake, Kolkata - 700 091, IN
3 Geological Survey of India, Flat#4, H/31M, BP Township, Kolkata - 700 094, IN
4 Geological Survey of India, Chemical Division, Eastern Region, DK-6, Salt Lake, Kolkata - 700 091, IN
1 Geological Survey of India, 27 Jawaharlal Nehru Road, Kolkata - 700 016, IN
2 Geological Survey of India, Op WB-SK-AN, Eastern Region, DK-6, Salt Lake, Kolkata - 700 091, IN
3 Geological Survey of India, Flat#4, H/31M, BP Township, Kolkata - 700 094, IN
4 Geological Survey of India, Chemical Division, Eastern Region, DK-6, Salt Lake, Kolkata - 700 091, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 68, No 6 (2006), Pagination: 1069-1086Abstract
The South Purulia Shear Zone (SPSZ) is a part of the conspicuous -E-W to -ESE-WNW trending Tamar-Porapahar lineament. This borders the Meso-Proterozoic greenschist facies lithopackage of the Singhbhum Group (SG) comprising metasedimentaries, felsic volcanics, mafites/Ultramafites, granitoids, and alkaline/Carbonatite suite of rocks bounded by the Chhotanagpur Gneissic Complex (CGC) attaining amphibolite to granulite facies in the north CGC presumably had certatn loci of crustal weakness where pre-Rift crustal sagging led to the deposition of supracrustal rocks. Intracratonic rifting had then initiated in those pre-Existing zones of crustal weakness and troughs of the resident crust. The intracratonic basin was covered by huge volume of the felsic volcanics represented by layered tuffaceous volcaniclastic, felsic ignimbrites, crystal-Vitric tuff and tuffaceous phyllite. Meta-Greywacke has been considered as epiclastic deposit derived from felsic volcanics. The nature of welding, absence of phenocrysts typical of lava flows, parallel aligned lenticular pumice fragments exhibiting pumice-Lenticle foliation, fiamme and eutaxitic fabric and petrochemistry could imply that the felsic igniimbrite was close to welded pumiceous ash-Flow tuff having dacitic to rhyodacitic composition. Mafic-ultramafic suites of rocks in close proximity to felsic volcanics suggest a bimodal character of magmatic episode in the area Bands and lenses of tourmalinite disposed along the contact of the CGC and the SG, argued to be of volcanogenic sedimentary origin, possibly demarcates the rupture locales of a rift. The alkali-Feldspar granite(± richterite, ± aegirine-augite), syenite and carbonatites suggest tapping of deeper fractures in the rifted basin. This was coupled with the presence of granite plutonism in the setting. Geochemical signatures imply that felsic volcanics are chiefly of dacitic composition with strong LREE enrichment and narrow range of fractionation while the metabasic rock chemistry scatter in basalt to basaltic andesite field. Trace element data further corroborate 'volcanic arc granite', ' Within plate granite' and 'continental arc granite' composition for the felsic volcanics. The basin was then subscribed to compressional regime where ductile shear zones developed syn to post kinematic to F1 with the northern block (CGC) thrusting over the southern block (SG) on northerly dipping planes. Thus, an entire sequence of rifting, tourmalinite emplacement, felsic volcanism, mafic extrusion, granite plutonism, syenite/Carbonatite emplacement and sedimentation of pelites/Epiclastics during and after opening of the basin in an intracratonic setting is demonstrated. Subsequently, development of the shear zone (SPSZ) took place over the area at the close of the basin.Keywords
Ignimbrite, Dacite, Tourmalinite, Rift, Shear, Petrography, Geochemistry, Purulia, West Bengal.- Li-Cs-Rb Mineralisation in Proterozoic Zoned Pegmatites of Beku, West Bengal
Abstract Views :186 |
PDF Views:2
Authors
Affiliations
1 Geological Survey of India, Op. WB-S-A&N, GSI Office Complex, DK-Block, Sector 11, Salt Lake City, Kolkata -700 091, IN
2 Geological Survey of India, Zorem building, Nongrim Hills, Shillong - 793 003, IN
1 Geological Survey of India, Op. WB-S-A&N, GSI Office Complex, DK-Block, Sector 11, Salt Lake City, Kolkata -700 091, IN
2 Geological Survey of India, Zorem building, Nongrim Hills, Shillong - 793 003, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 60, No 5 (2002), Pagination: 493-503Abstract
The Li-Cs-Rb bearing Beku pegmatite occurs in a calc-silicate rock enclave within the Proterozoic Chhotanagpur Gneissic Complex (CGC). Its internal structure shows zonation that comprises an outer tourmaline-rich pegmatite and inner rare metal-bearing pegmatite containing spodumene-pollucite-lepidolite. The pegmatite is strongly peraluminous with high SiO2, low Fe2O3(t), CaO, TiO2, P2O, and variable Al2O3, K2O and Na2O. Its Cs/Rb and Li/Rb values increase towards the centre and decrease towards the boundary. K/Rb value increases from pollucite-bearing pegmatite to tourmaline-rich pegmatite, depicting the more evolved nature of the pollucite-bearing pegmatite. Petrography and geochemistry of the Beku pegmatite suggest fractionation from a peraluminous S-type granitic magma. It is synchronous with shear development in the area, under a minimum formational P-T of 4 kbar and 500°C.Keywords
Rare Metal (Li-Cs-Rb) Pegmatite, Calc Silicate Rock, Proterozoic, Chhotanagpur Gneissic Complex, Beku, West Bengal.- A Comparative Experimental Study on Fast Hole near Dry EDM of Stavax with Different Dielectric Coupled with Surface Response Curves
Abstract Views :301 |
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Authors
Affiliations
1 MGM’S Research Centre, Nanded, IN
2 Department of Production Engineering and Industrial Management, College of Engineering, Pune, IN
1 MGM’S Research Centre, Nanded, IN
2 Department of Production Engineering and Industrial Management, College of Engineering, Pune, IN
Source
Manufacturing Technology Today, Vol 13, No 8 (2014), Pagination: 3-11Abstract
This paper presents comparative experimental study on machining characteristics of through holes (1000 micron) produced on special alloy steel, Stavax, thick plate with different types of dielectrics. Fast hole rotary Near Dry EDM (NDEDM) machine using tubular hollow brass electrodes are used for machining. Several holes are drilled using identical input parameters based on full factorial design of experiment procedure with four center points. Corresponding values of Material Removal Rate (MRR), Tool Wear Rate (TWR), MRR /TWR ratio & % Electrode Ratio are calculated and compared. The empirical relationship for above responses are developed using Regression Analysis. Surface Response Curves are plotted to compare response of interest. The results revealed that MRR,TWR & MRR/TWR (λ) ratio depends up on appropriate selection of input parameters as well as selection of dielectric.Keywords
Near Dry Electro Discharge Machining (NDEDM), MRR, TWR, Surface Response Curves.- Optimization of the Machining Parameters in Wire Electrical Discharge Machining Process Using Genetic Algorithm
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Authors
M. S. Kadam
1,
S. K. Basu
2
Affiliations
1 Production Engg. Dept., Jawaharlal Nehru Engg. College, Aurangabad-431006, IN
2 Production Engg. Dept., College of Engg., Pune-411005, IN
1 Production Engg. Dept., Jawaharlal Nehru Engg. College, Aurangabad-431006, IN
2 Production Engg. Dept., College of Engg., Pune-411005, IN