A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Padmanaban, G.
- Innovation – which Way?
Authors
1 Department of Biochemistry, Indian Institute of Science, Bengaluru 560 012, IN
Source
Current Science, Vol 109, No 10 (2015), Pagination: 1759-1760Abstract
No Abstract.- Nobel Shot in the Arm for Neglected Infectious Disease Research
Authors
1 Department of Biochemistry, Indian Institute of Science, Bengaluru 560 012, IN
Source
Current Science, Vol 109, No 9 (2015), Pagination: 1537-1540Abstract
No Abstract.- Developing Empirical Relationship to Predict Hardness of the Laser Hardfaced Ni-Based Alloy Surfaces
Authors
1 Centre for Materials Joining & Research (CEMAJOR), Department of Manufacturing Engineering, Annamalai University, Annamalainagar, Tamil Nadu, IN
2 Material Technology Division, Indira Gandhi Center for Atomic Research (IGCAR), Kalpakam, IN
Source
Manufacturing Technology Today, Vol 16, No 1 (2017), Pagination: 9-17Abstract
Nuclear reactor components generally undergo wear damage due to severe operating conditions. The operating temperature of nuclear components generally falls in the range of 573-873 K. Among the reactor components, feed water regulator valves, used to throttle coolant flow, experiences higher wear rate. To enhance the wear resistance, nickel (Ni) and cobalt (Co) based alloys are hardfaced into austenitic stainless steels (ASS) through laser hardfacing technique. Laser hardfacing technique is an established surfacing process to deposit Ni base alloys with minimum dilution. Though lot of research works have been carried out so for to characterize laser hardfaced Ni base alloy surfaces, there is no direct correlation between laser parameters and hardness of the hardfaced surfaces. Hence in this investigation, an attempt has been made to develop empirical relationship to predict hardness of laser hardfaced Ni base alloy surface incorporating laser parameters using statistical tools such as design of experiments (DoE), analysis of variance (ANOVA). The developed empirical relationship can be effectively used to trail the hardness of laser hardfaced nickel alloy surfaces by altering laser parameters.Keywords
Austenitic Stainless Steel, Laser Hardfacing, Design of Experiment, Hardness.References
- Atamert, S; Bhadeshia, HKDH: Comparison of the Microstructures and Abrasive Wear Properties of Stellite Hardfacing Alloys Deposited by Arc Welding and Laser Cladding. 'Metallurgical Transactions A', vol. 20, no. 6, 1989, 1037–54.
- Frenk, A; Kurz, W: High Speed Laser Cladding: Solidification Conditions and Microstructure of a Cobalt-Based Alloy, 'Materials Science and Engineering A', vol. 173, no. 1-2, 1993, 339–342.
- Tiziani, A; Giordano, l; Matteazzi, P; Badan, B: Laser Stellite Coatings on Austenitic Stainless Steels, 'Materials Science and Engineering', vol. 88, 1987, 171–175.
- Arif, AFM; Yilbas, BS: Laser Treatment of HVOF Coating: Modeling and Measurement of Residual Stress in Coating, 'Journal of Materials Engineering and Performance', vol. 17, no. 5, 2008, 644–650.
- Liu, Z; Cabrero, J; Niang, S and Al-Taha, ZY: Improving Corrosion and Wear Performance of HVOF-Sprayed Inconel 625 and WC-Inconel 625 Coatings by High Power Diode Laser Treatments, 'Surface and Coatings Technology', vol. 201, no. 16-17, 2007, 7149–58.
- Navas, C; Vijande, R; Cuetos, JM; Fernández, MR; J de Damborenea: Corrosion Behaviour of NiCrBSi Plasma-Sprayed Coatings Partially Melted with Laser, 'Surface and Coatings Technology', vol. 201, no. 3-4, 2006, 776–785.
- Schmidt, RD; Ferriss, DP: New Materials Resistant to Wear and Corrosion to 1000±C, 'Wear', vol. 32, no. 3, 1975, 279–289.
- Davis, Joseph R: ASM Specialty Handbook: Nickel, Cobalt, and Their Alloys, 'ASM International', Materials Park, 2000.
- Halstead, A; Rawlings, RD: Structure and Hardness of Co-Mo-Cr Si Wear Resistant Alloys (Tribaloys), 'Metal Science', vol. 18, no. 10, 1984, 491–500.
- Mason, SE; Rawlings, RD: Structure and hardness of Ni–Mo–Cr–Si wear and corrosion resistant alloys, 'Materials Science and Technology', vol. 5, no.2, 1989, 180-185
- Sauthoff, Gerhard, Intermetallics, 1995.
- Liu, CT; Zhu, JH; Brady, MP; McKamey, CG; Pike, LM: Physical Metallurgy and Mechanical Properties of Transition - Metal Laves Phase Alloys, vol. 8, no. 9-11, 2000, 1119–1129.
- Navas, C; Cadenas, M; Cuetos, JM; J. de Damborenea: Microstructure and Sliding Wear Behaviour of Tribaloy T-800 Coatings Deposited by Laser Cladding, 'Wear', vol. 260, no. 7-8, 2006, 838–846.
- Przybylowicz, J; Kusinski, J: Laser Cladding and Erosive Wear of Co – Mo – Cr – Si Coatings, 'Surface & Coatings Technology', vol. 125, no. 1-3, 2000, 13–18.
- Lin, WC; Chen, C: Characteristics of Thin Surface Layers of Cobalt-Based Alloys Deposited by Laser Cladding, 'Surface and Coatings Technology', vol. 200, no. 14-15, 2006, 4557–4563.
- Price, M; Wolfl, TA: The Microstructures and Mechanical Properties of a Series of Plasma and Detonation Coatings of Cobalt and Nickel Alloys with Molybdenum, Two of the Coatings Were St’, vol. 45, 1977, 309–19.
- Bolelli, G; Lusvarghi, L: Heat Treatment Effects on the Tribological Performance of HVOF Sprayed Co-Mo-Cr-Si Coatings, 'Journal of Thermal Spray Technology', vol. 15, no. 4, 2006, 802–810.
- Zhang, H; Shi, Y; Kutsuna, M; Xu, GJ: Laser cladding of Colmonoy 6 powder on AISI316L austenitic stainless steel, 'Nuclear Engineering and Design', vol. 240, no. 10, 2010, 2691-2696.
- Siva, K; Murugan, N; Logesh, R: Optimization of weld bead geometry in plasma transferred arc hardfaced austenitic stainless steel plates using genetic algorithm, 'Int J Adv Manuf Technology', vol. 41, no. 1, 2009, 24-30.
- Kesavan, D; Kamaraj, M: The microstructure and high temperature wear performance of a nickel base hardfaced coating, ‘Surface & Coatings Technology’, vol. 204, no. 24, 2010, 4034-4043
- Optimizing the Pulsed Current GTAW Process Parameters to Attain Maximum Tensile Strength Using RSM
Authors
1 Centre for Materials Joining & Research (CEMAJOR), Department of Manufacturing Engineering, Annamalai University, Annamalainagar-608002, Tamil Nadu, IN
Source
Indian Welding Journal, Vol 47, No 4 (2014), Pagination: 43-56Abstract
In this investigation, an attempt has been made to predict the tensile strength of pulsed current gas tungsten arc welded (PCGTAW) AZ31B magnesium alloy joints using RSM incorporating process parameters such as peak to base current ratio, welding speed, pulse frequency and pulse on time as variables. The experiments were conducted based on a four-factor, five-level, central composite design matrix. The developed empirical relationship can be effectively used to predict the tensile strength of PCGTAW joints of AZ31B magnesium alloy at 95% confidence level. The results indicated that welding speed and pulse frequency has the greatest influence on tensile strength, followed by current ratio, pulse on time. Response surface methodology (RSM) was used to optimize PCGTAW parameters to attain a maximum tensile strength of 214 MPa (78 % of base metal strength) in the AZ31B Magnesium alloy joints.Keywords
AZ31B Magnesium Alloy, Pulsed Current Gas Tungsten Arc Welding, Response Surface Methodology, Optimization, Tensile Strength.- Relevance of Modern Technologies to Indian Agriculture
Authors
1 Department of Biochemistry, Indian Institute of Science, Bengaluru 560 012, IN
Source
Current Science, Vol 114, No 12 (2018), Pagination: 2432-2433Abstract
The five-point programme suggested by Swaminathan and Kesavan to ‘End hunger, achieve food security and improved nutrition and promote sustainable agriculture’ (UN Sustainable Development Goals (SDGs)) is unexceptional. One understands the need for providing adequate calories, end protein hunger, overcome micronutrient deficiencies, access to clean drinking water and attention to imparting nutrition literacy to the community. However, it is surprising that the authors summarily dismiss genetic engineering technology as not sustainable based on a superficial analysis. The fact remains that introduction of Bt-cotton transformed this country from a cotton-importing destination to that of a cotton-exporting nation. One needs to analyse the reasons for its diminishing efficacy and ensure sustainability.References
- Swaminathan, M. S. and Kesavan, P. C., Curr. Sci., 2018, 114(8), 1585–1586.
- Effect of Tool Materials on Tensile Properties of Friction Stir Welded AZ31B Magnesium Alloy
Authors
1 Centre for Materials Joining & Research, Manufacturing Dept., Annamalai University, IN
Source
Indian Welding Journal, Vol 42, No 1 (2009), Pagination: 25-32Abstract
In this investigation, an attempt was made to study the effect of tool materials on tensile properties of friction stir welded AZ31B magnesium alloy. Tools made of five different materials were used to fabricate the joints. Tensile properties of the joints were evaluated and correlated with the weld zone microstructure and hardness. From this investigation, it is found that the joint fabricated using the tool made of high carbon steel exhibited superior tensile properties compared to their counterparts. The absence of defects in weld region, presence of very fine equiaxed grains in the weld region and higher hardness in the weld region are the main reasons for superior tensile properties of these joints.
Keywords
Magnesium Alloy, Friction Stir Welding, Tensile Properties, Tool Material.- India Needs Genetic Modification Technology in Agriculture
Authors
1 Department of Botany, University of Calcutta, Kolkata 700 019, IN
2 Punjab Agricultural University, Ludhiana 141 004, IN
3 Protection of Plant Varieties and Farmers’ Right Authority, Ministry of Agriculture, Government of India, Societies Block, NASC Complex, DPS Marg, New Delhi 110 012, IN
4 Agrasen Apartment, Plot 10, Sector 7, Dwarka, New Delhi 110 075, IN
5 Division of Rural Development, JSS Mahavidyapeetha, Mysuru 570 004, IN
6 Raviram Residency, 13/1 Chitale Marg, Dhantoli, Nagpur 440 012, IN
7 Department of Biochemistry, Indian Institute of Science, Bengaluru 560 012, IN
8 Institute of Life Sciences, Bhubaneswar 751 023, IN
9 Trust for Advancement of Agricultural Sciences, Avenue II, Pusa Campus, Indian Agricultural Research Institute, New Delhi 110 012,, IN
10 Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar 382 007, IN
11 National Agri-Food Biotechnology Institute, Knowledge City, Mohali 140 306,, IN
12 ICAR-National Research Centre on Plant Biotechnolgy, Pusa Campus, New Delhi 110 012, IN
13 National Academy of Agricultural Sciences, NASC Complex, Dev Prakash Shastri Marg, Pusa, New Delhi 110 012, IN
14 National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi 110 067, IN
15 Department of Plant Molecular Biology, University of Delhi, South Campus, New Delhi 110 021, IN
16 Advanced Centre for Plant Virology, Indian Agricultural Research Institute, New Delhi 110 012, IN
17 School of Biotechnology, Madurai Kamaraj University, Madurai 625 021, IN
Source
Current Science, Vol 117, No 3 (2019), Pagination: 390-394Abstract
India does not have a clear stand on the release and consumption of genetically modified crops (food). The only approved crop is Bt-cotton, which has put India on the global map as a cotton exporting country. Even so, Bt-brinjal is under moratorium and GM mustard is prevented from undergoing commercial trial. All these decisions are not based on sound scientific principles. Activism against has successfully prevented exploitation of a powerful technology that can contribute to India’s food and nutrition security. This article attempts to give a balanced perspective of genetic modification technology as one of the serious options to be considered on case to case basis. Ambivalence will seriously affect India’s food security in the future.Keywords
Bt-Cotton, Food Security, Gene Editing, Genetically Modified Crops, Mustard.References
- Kesavan, P. C. and Swaminathan, M. S., Modern technologies for sustainable food and nutrition security. Curr. Sci., 2018, 115, 1876–1883.
- National Academies of Sciences, Engineering and Medicine, Genetically Engineered Crops: Experiences and Prospects, The National Academy Press, 2016; https://doi.org/10.17226/23395.
- European Commission, a decade of EU-funded GMO research (2001–2010), 2010; ec, europa.eu/research/biosociety/pdf/a_decade_of_eu-funded_gmo_reserach.pdf.).
- Klumper, W. and Qaim, M. A., Meta-analysis of the impacts of genetically modified crops. PLOS ONE, 2014, 9, e111629; doi:10.1371/journal.pone.0111629.
- Eenennaam, A. L. and Young, A. E., Prevalence and impacts of genetically engineered feedstuffs on livestock populations. J. Anim. Sci., 2014, 92, 4255–4278.
- Cotton Corporation of India – Statistics, Government of India undertaking; https://cotcorp.org.in/statistics.aspx
- Brookes, G. and Barfoot, P., Farm income and production impacts of using GM crop technology 1996–2016. GM Crops Food, 2018, 9, 1–31.
- Brookes, G. and Barfoot, P., Environmental impacts of genetically modified (GM) crop use 1996–2016: impacts on pesticide use and carbon emissions. GM Crops Food, 2018, 9, 109–139.
- Krishna, V. and Qaim, M. B., Bt-cotton and sustainability of pesticide reduction in India. Agric. Syst., 2012, 107, 47–55.
- Plewis, I., Indian farmer suicides – is GM cotton to blame? Significance, 2014, 11, 14–18.
- Plewis, I., Hard evidence: does GM cotton lead to farmer suicide in India? In The Conversation, 2014; Theconversation.com.hard.evidence-does-gm-cotton-lead-to-farmer-suicide-in-india-24045.
- Shukla, K. A., et al., Expression of an insecticidal fern protein protects against white fly. Nature Biotechnol., 2016, 34, 1046– 1051.
- Lynas, M., Seeds of Science, Bloomsbury Sigma. United Kingdom, 2018, pp. 118–123.
- Shelton, A. M. et al., Bt eggplant project in Bangladesh: history, present status and future direction. Front. Bioeng. Biotechnol., 2018; https://doi.org/10.3389/fbioe.2018.00106.
- Food Standards Australia/New Zealand (FSANZ). Response to Seralini paper, October 2016.
- Glyphosate: EFSA updates toxicological profile, 2015; www.efsa.europa.eu/en/press/news/151112.
- Alberts, B. et al., Standing up for GMOs. Science, 2013, 341, 1320.
- Kaur, N. et al., CRISPR/Cas9-mediated efficient editing in phytoene desaturase (PDS) demonstrates precise manipulation in banana cv. Rasthali genome. Funct. Integr. Genomics, 2018, 18, 89–99; doi.org/10.1007/s10142-017-0577-5.
- Kumar, S., Bhatnagar, R. K., Kranthi, K. R. and Datta, S., The legal battle over field trials of GM crops. Nature India, 2014; doi:10.1038/nindia.2014.
- National Academy of Agricultural Sciences, Policy brief: to accelerate utilization of GE technology for food and nutrition security and improving farmers’ income, NAAS, New Delhi, 2016.
- Biology without borders
Authors
1 Bhabha Atomic Research Centre, Mumbai 400 085, IN
2 Department of Biochemistry, Indian Institute of Science, Bengaluru 560 012, IN