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Rice science 2013年第6期20卷 415-426页

作者： P.MANIMARAN G.RAVI KUMAR M.RAGHURAMI REDDY S.JAIN t.bhaskar rao S.K.MANGRAUtHIA R.M.SUNDARAM S.RAVICHANDRAN S.M.BALACHANDRAN Biotechnology Laboratory Crop Improvement SectionDirectorate of Rice ResearchRajendranagarHyderabad 500030India

A rapid and reproducible method to develop transgenic plants with enhanced transformation efficiency using Agrobacterium has been developed for the elite indica rice variety BPt 5204. Different rice calli aged from 3 to 30 d were co-cultivated with pre-incubated Agrobacterium suspension culture （LBA4404： pSB1, pCAMBIA1301） and incubated in dark for 3 d. Based on the transient GUS gene expression analysis, 6-day-old young calli showed high transformation frequency followed by 21-day-old ones. thus, both 6-and 21-day-old calli were used for assessing the stable transformation efficiency. It was observed that the 6-day-old young transformed calli showed about 2-fold higher regeneration frequency when compared with 21-day-old calli. the transformation efficiency was enhanced for young calli to 5.9% compared with 0.8% of the 21-day-old calli. Molecular and genetic analysis of transgenic plants （to） revealed the presence of 1-2 copies of t-DNA integration in transformants and it follows Mendalian ratio in t1 transgenic plants. From the present study, it was concluded that the development of transgenic rice plants in less duration with high regeneration and transformation efficiency was achieved in BPt 5204 by using 6-day-old young calli as explants.

关键词： Agrobacterium-mediated transformation meihod rice callus transformation transgenicplant indica rice

Effectiveness of sodium silicate as gangue depressants in iron ore slimes flotation

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 515-522页

作者： Danda Srinivas rao tadiparthi Venkata VijayaKumar Sripada Subba rao Swarna Prabhakar Guntamadugu bhaskar Raju National Metallurgical Laboratory-Madras Centre Council of Scientific and Industrial Research-Madras ComplexChennai 600 113India

the recovery of iron from the screw classifier overflow slimes by direct flotation was studied. the relative effectiveness of sodium silicates with different silica-to-soda mole ratios as depressants for silica and silicate bearing minerals was investigated. Silica-to-soda mole ratio and silicate dosage were found to have significant effect on the separation efficiency. the results show that an increase of Fe content in the concentrate is observed with concomitant reduction in SiO2 and A1203 levels when a particular type of sodium silicate at a proper dosage is used. the concentrate of 58.89wt% Fe, 4.68wt% SiO2, and 5.28wt% A1203 with the weight recovery of 38.74% and the metal recovery of 41.13% can be obtained from the iron ore slimes with 54.44wt% Fe, 6.72wt% SiO2, and 6.80wt% A1203, when NazSiO3 with a silica-to-soda mole ratio of 2.19 is used as a depressant at a feed rate of 0.2 kg/t.

关键词： iron ores sodium silicate depressants flotation

Geochemical assessment of a siliceous limestone sample for cement making

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Chinese Journal Of Geochemistry 2011年第1期30卷 33-39页

作者： rao D.S. Vijayakumar t.V. Prabhakar S. bhaskar Raju G. National Metallurgical Laboratory-Madras Centre CSIR Madras Complex Taramani Chennai-600 113 India

A low grade siliceous limestone sample from the Jayantipuram mine of Andhra Pradesh, India, has been investigated for its suitability for cement making. Petrological as well as X-ray diffraction pattern studies indicated that the limestone sample was crystalline and dominantly composed of calcite and quartz. they are simple in mineralogy, and yet they have variable silica and lime contents. Geochemical analysis results of twenty five hand picked samples indicated that the limestone from the Jayantipuram mine shows a wide range of variations in LOI (29.94% to 40.64%), SiO2 (6.14% to 27.18%), CaO (37.93% to 50.78%), Al2O3 (0.49% to 2.27%) and Fe2O3 (0.28% to 2.4%). MgO, K2O, Na2O, tiO2 and MnO2 are present in traces. CaO with LOI shows a strong positive correlation where as CaO with SiO2 shows a strong negative correlation because of mineralogical factors. the chemical composition of the limestone reflects its mineralogical composition. the distribution of various elements in the acid-soluble fraction has been studied by the factor analysis method in order to interpret in terms of their mineralogy, sedimentary environment and diagenesis. Mineralogy, recrystallization and other diagenetic changes are the main factors affecting the distribution of the elements and their mutual relationships in the limestone. the aim of this paper is also to analyze how significantly the two parameters, silica modulus and lime saturation factor, influence this low grade siliceous limestone sample from the Jayantipuram mine of Andhra Pradesh, India, for the cement making process from the geochemical data.

关键词：灰岩样品水泥生产地球化学硅质石灰石矿评估因子分析方法化学数据处理

Beneficiation of a low grade limestone sample

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Mining Science and technology 2011年第5期21卷 631-636页

作者： rao Danda Srinivas Vijayakumar tadiparthi Venkata Subba rao Sripada bhaskar Raju Guntamadugu Prabhakar Swarna National Metallurgical Laboratory Madras Centre CSIR Madras Complex Chennai 600 113 India

Pilot scale column flotation studies were conducted on a low grade siliceous limestone ore. Silica content was reduced to less than 13g in the concentrate so that it became satisfactory for use in the paper or rubber industries. the limestone sample was crystalline and constituted primarily of calcite that contained quartz, feldspar, pyroxene, and biotite as gangue minerals. Quartz is the major silicate gangue whereas feldspar, pyroxene, and biotite exist in minor to trace quantities. traces of pyrite were also observed within the sample. A reverse flotation process was adopted where the silicate gangue minerals were floated using two different commercial cationic collectors： Chem-750 F or Floatamine-D. the studies clearly suggest it is possible to produce a limestone concentrate assaying around 96-97% CaCO3 containing less than 1 % Si02. the effect of feed flow rate, percent solids, froth depth, and wash water on the grade and recovery of the CaC03 concentrate is discussed.

关键词： Low grade limestoneReverse flotationColumn flotationCationic collector

Flotation studies on low grade graphite ore from eastern India

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International Journal of Mining Science and technology 2015年第3期25卷 415-420页

作者： Vasumathi N. Vijaya Kumar t.V. Ratchambigai S. Subba rao S. bhaskar Raju G. CSIR-National Metallurgical Laboratory Madras Centre CSIR Madras Complex

A low grade graphite ore from eastern India was beneficiated by flotation to improve its quality. the ore was composed of 87.80%ash and 8.59%fixed carbon. Primary coarse wet grinding （d80：186 μm） followed by rougher flotation in Denver flotation cell using diesel as collector and pine oil as frother yielded a rougher concentrate. Regrinding （d80：144 μm） of this rougher concentrate was opted for further libera-tion of graphite. It was followed by cleaning in laboratory flotation column. this combined process of relatively coarse primary grinding followed by regrinding and cleaning in flotation column resulted in final concentrate of 7.44% yield with 89.65% fixed carbon and 6.00% ash. this approach of two-stage grinding to recover the flake graphite at the coarsest possible grind can help to minimize grinding energy costs. A conceptual flow sheet which is cost effective was developed based on this methodology.

关键词： Graphite Liberation Froth flotation Column flotation Flow-sheet development

Comprehensive screening for reg1α gene rules out association with tropical calcific pancreatitis

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World Journal of Gastroenterology 2007年第44期13卷 5938-5943页

作者： Swapna Mahurkar Seema bhaskar D Nageshwar Reddy G Venkat rao Giriraj Ratan Chandak Genome Research Group Centre for Cellular and Molecular Biology Uppal Road Hyderabad 500 007 India Asian Institute of Gastroenterology Punjagutta Hyderabad 500 082 India

AIM: to investigate the allelic and haplotypic association of reg1α gene with tropical calcific pancreatitis (tCP). Since tCP is known to have a variable genetic basis, we investigated the interaction between mutations in the susceptibility genes, SPINK1 and CtSB with reg1α polymorphisms. MEtHODS: We analyzed the polymorphisms in the reg1α gene by sequencing the gene including its promoter region in 195 tCP patients and 150 ethnically matched controls, compared their allele and haplotype frequencies, and their association with the pathogenesis and pancreaticolithiasis in tCP and fibro-calculous pancreatic diabetes. RESULtS: We found 8 reported and 2 novel polymo-rphisms including an insertion-deletion polymorphism in the promoter region of reg1α. None of the 5' UtR variants altered any known transcription factor binding sites, neither did any show a statistically significant association with tCP. No association with any reg1α variants was observed on dichotomization of patients based on their N34S SPINK1 or L26V CtSB status. CONCLUSION: Polymorphisms in reg1α gene, including the regulatory variants singly or in combination with the known mutations in SPINK1 and/or CtSB genes, are not associated with tropical calcific pancreatitis.

关键词： tropical calcific pancreatitis Lithostathine Stone formation Polymorphism Haplotype

Biomechanics of knee joint-- A review

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Frontiers of Mechanical Engineering 2015年第2期10卷 176-186页

作者： bhaskar Kumar MADEtI Srinivasa rao CHALAMALASEttI S. K. Sundara siva rao BOLLA PRAGADA Department of Mechanical Engineering Gayatri Vidya Parishad Collegeof Engineering Visakhapatnam 530048 India Department of Mechanical Engineering AU College of EngineeringAndhra University Visakhapatnam 530003 India

the present paper is to know how the work is carried out in the field of biomechanics of knee. Various model formulations are discussed and further classified into mathematical model, two-dimensional model and three-dimensional model. Knee geometry is a crucial part of human body movement, in which how various views of knee is shown in different planes and how the forces act on tibia and femur are studied. It leads to know the forces acting on the knee joint. Experimental studies of knee geometry and forces acting on knee shown by various researchers have been discussed, and comparisons of results are made. In addition, static and dynamic analysis of knee has been also discussed respectively to some extent.

关键词： biomechanics knee geometry ligaments squat femorotibial joint finite element method

A new cache of Eoarchaean detrital zircons from the Singhbhum craton,eastern India and constraints on early Earth geodynamics

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Geoscience Frontiers 2019年第4期10卷 1359-1370页

作者： Bulusu Sreenivas Sukanta Dey Y.J. bhaskar rao t. Vijaya Kumar E.V.S.S.K. Babu Ian S. Williams CSIR-National Geophysical Research Institute Hyderabad 500007India Department of Earth Sciences Indian Institute of Science Education and ResearchKolkata 741246India Research School of Earth Sciences The Australian National UniversityCanberra 2601Australia

the dominant geodynamic processes that underpin the formation and evolution of Earth’s early crust remain enigmatic calling for new information from less studied ancient cratonic ***,we present U-Pb ages and Hf isotopic compositions of detrital zircon grains from^2.9 Ga old quartzites and magmatic zircon from a 3.505 Ga old dacite from the Iron Ore Group of the Singhbhum craton,eastern *** detrital zircon grains range in age between 3.95 Ga and 2.91 *** with the recently reported Hadean,Eoarchean xenocrystic(up to 4.24 Ga)and modem detritus zircon grains from the Singhbhum craton,our results suggest that the Eoarchean detrital zircons represent crust generated by recycling of Hadean felsic crust formed at^4.3-4.2 Ga and^3.95 *** observe a prominent shift in Hf isotope compositions at^3.6-3.5 Ga towards super-chondritic values,which signify an increased role for depleted mantle and the relevance of plate *** Paleo-,Mesoarchean zircon Hf isotopic record in the craton indicates crust generation involving the role of both depleted and enriched mantle *** infer a short-lived suprasubduction setting around^3.6-3.5 Ga followed by mantle plume activity during the Paleo-,Mesoarchean crust formation in the Singhbhum *** Singhbhum craton provides an additional repository for Earth’s oldest materials.

关键词： U-Pb zircon ages Hf isotopes Singhbhum craton Hadean Eoarchean Geodynamics

Beneficiation of an Indian non-coking coal by column flotation

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International Journal of Coal Science & technology 2016年第2期3卷 206-214页

作者： N. Vasumathi t. V. Vijaya Kumar S. Ratchambigai S. Subba rao S. Prabhakar G. bhaskar Raju CSIR-National Metallurgical Laboratory Madras Centre CSIR Madras Complex Taramani Chennai 600 113 India

Beneficiation of non-coking coal is gaining ground in India. It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses. For special applications such as the fuel for integrated gasification combined cycle plant （IGCC）, the ash content in the coal should preferably be below 15 %. Indian coals are characterized by high inter-grown ash content mainly due to ＇drift origin＇ of Gondwana formation in Permian age. this warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals. A non- coking coal sample of vitrinite type from India was ground to 44 ~tm （dso） and subjected to column flotation to improve its quality. the non-coking coal analyzing 34.6 % ash, 26.2 % volatile matter, 1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters, namely, froth depth, superficial feed velocity and superficial air velocity. the concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route.

关键词： Non-coking coal Washability Beneficiation Column flotation Coal gasification

Investigation of structural,magnetic and optical properties of rare earth substituted bismuth ferrite

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Journal of Rare Earths 2013年第4期31卷 370-375页

作者： t.Durga rao t.Karthik Saket Asthana Advanced Functional Materials Laboratory Department of PhysicsIndian Institute of Technology Hyderabad Department of Materials Science and Engineering Indian Institute of Technology Hyderabad

Polycrystalline BiFeO3 and rare earth substituted ***3 （BRFO, R=Y, Ho and Er） compounds were prepared by rapid solid state sintering technique. Structural phase analysis indicated that all the compounds stabilized in rhombohedral structure （R3c space group） and a small orthorhombic phase fraction was observed in BRFO compounds. From the Raman spectra results, the changes in the phonon frequencies （A1） and line widths suggested lattice distortion in the BRFO compounds as was evidenced in the XRD analysis. Compared to the linear variation of magnetization with magnetic field （M-H） shown by BFO, an obvious M-H loop was observed in BRFO compounds which could be due to the suppression of space modulated spin structure and was explained on the basis of weak ferromagnetism and field induced spin reorientation. UV-Vis spectroscopy evidenced a change in local FeO6 envi- ronment due to shift in the 6Alg→4t2g energy transition band. BRFO compounds with improved remnant magnetization and coercive field are applicable for magnetoelectric devices.

关键词： structural distortion spin-reorientation G-type antiferromagnet rare earths