Arun M. Umarji
Professor

Ph:
Off: +91-80-2293 2944
Res: +91-80-2337 5479
Fax: +91-80-2360 7316
E-mail: umarji@mrc.iisc.ernet.in

Brief Biodata:

Following his Ph. D.. from IIT, Madras in 1980, Prof. Umarji held post doctoral positions at IIT Madras, Argonne National Laboratory, USA and at TIFR in Mumbai. He has been a faculty member of the Materials Research Centre since 1987. He was a visiting faculty member (1997-98) at the Ceramics and Materials Eng. Department,Rutgers University, Piscataway, NJ- USA.

Research:
Metal Oxide based Gas Sensors
Developing VO2 thin films for bolometric applications
Thermoelectric materials

Research:

  • Metal Oxide based Gas Sensors
  • Developing VO2 thin films for bolometric applications
  • Thermoelectric materials

Research in Brief:

Metal Oxide based Gas Sensors

Metal oxide semiconducting gas sensors are one of the most investigated groups of gas sensors till date. These have attracted the attention of many users and scientists interested in gas sensing under atmospheric conditions due to their low cost and flexibility associated to their production and operation.

The performance of these semiconducting metal oxide gas sensors depends on their structural and electronic properties such as microstructure, local doping, grain boundaries and surface states. These properties are influenced by the preparation techniques used for producing the gas sensor device. Hence it becomes interesting to study the effect of synthesis route employed, on the performance parameters of the gas senor.

Thin films of Chromium oxide (Cr2O3) and Tin oxide (SnO2) have been identified as a good candidate of metal oxide semiconductor for exploring their gas sensing properties. Chromium Oxide is a p-type semiconductor. It shows good response to various gases like H2, NH3, VOCs and NOx etc. So far, gas sensing properties of chromium Oxide has not been explored fully. On the other hand, Tin Oxide (SnO2) is a well established gas sensor material. It is being used in commercially available gas sensing devices.

Our aim is to study gas sensing properties of the films Produced by UNSPACM and compare it with well established methods like normal spray pyrolysis and MOCVD. The preparation of the above oxides in thin film form has been adopted by two following methods, i.e metal organic chemical vapor deposition (MOCVD) and the nebulized spray pyrolysis of a combustion mixture. The gas sensing properties of these films have been studied.

Developing VO2 thin films for bolometric applications

Developing Infrared thermal imaging devices like bolometers have become very popular of their applications in night surveillance, remote sensing, night vision cameras, biomedical equipment, fire and intruder alarms. IR detectors are classified into photon detectors and uncooled thermal detectors. Though photon detectors offer high sensitivity and quick operation, their cooling apparatus occupy large volume and is not cost effective as well. These uncooled thermal detectors are called bolometers and they employ a thermal sensing layer whose variation in electrical resistance as a function of temperature is measured. The heating of this layer due to absorption of infrared radiation, results in its variation of electrical resistance with respect to temperature. Some of the materials used commonly in IR bolometers are Si and Vanadium oxides.

Vanadium oxides are being used as the thermal sensing layer because of their large temperature coefficient of resistance, favorable electrical resistance, reduced noise (low 1/f) and compatibility with the machining process. Of all oxides of vanadium, only vanadium dioxide has been highly investigated as it shows first order transition near to room temperature. First order transition is understood as the sharp change in the electrical resistance at a particular temperature when resistance is measured as a function of temperature. The change in resistivity in this case is of the order of 105 over a temperature change of 0.1oC at 68oC in a single crystal. The main objective of this work is developing doped vanadium dioxide thin films prepared by Ultrasonic Nebulized Spray Pyrolysis of Aqueous Combustion Mixture in order to have reduced first order transition (close to room temperature) and understanding its transition characteristics.

Thermoelectrics

Silicides are a potential candidate for High temperature applications such as heating elements, protective coatings, ceramic engines etc. because of its non-toxicity, availability of raw materials, chemical and thermal stability. Despite its advantages, the thermoelectric performance (zT) of the material is low. So efforts are on in enhancing the thermoelectric performance of the material. Band structure engineering and phonon engineering are some of the methodologies in improving the material’s properties. This can be done by chemical doping and nanostructurization. This in turn can be carried out by doping the material with Mn, Co, B, etc. Nanostructurization can enhance zT value by decreasing the thermal conductivity.

Recent Publications:

    1. Angadi, B., M.R. Ajith, and A.M. Umarji, Synthesis, microstructure and thermal expansion studies on Ca5+x/2Sr5+x/2Zr4P6-2x Si2x O24 system prepared by co-precipitation method, Bulletin of Materials Science., 87 36 (2014)
    2. Goswami Ankur, Ankit K., Balashanmugam. N., Umarji Arun M., Madras Giridhar, Optimization of rheological properties of photopolymerizable alumina suspensions for ceramic microstereolithography Ceramics International, 3655 40 (2014)
    3. Goswami Ankur,Umarji Arun M., Madras Giridhar, Study of Thermal Relaxation of Poly (HDDA-co-MMA) by Temperature Modulated DSC and Dielectric Spectroscopy Polymer-Plastics Technology and Engineering, 485 52 (2013)
    4. Kamble Vinayak B., Bhat, S. V., Umarji, A. M., Investigating thermal stability of structural defects and its effect on d0 ferromagnetism in undoped SnO2 Journal of Applied Physics, 113 (2013)
    5. Kamble Vinayak B., Umarji, A. M., Defect induced optical bandgap narrowing in undoped SnO2 nanocrystals Aip Advances,3 (2013)
    6. Kamble Vinayak B., Umarji, A. M., Gas sensing response analysis of p-type porous chromium oxide thin films Journal of Materials Chemistry C, 8167 1 (2013)
    7. Perumal.S, Gorsse S., Ail, U.,Chevalier, B.,Decourt, R., Umarji, A. M Effect of co-substitution of Mn and Al on thermoelectric properties of chromium disilicide Journal of Materials Science, 227 48 (2013)
    8. Perumal.S, Gorsse S., Ail, U.,Chevalier, B.,Decourt, R., Umarji, A. M Effect of Composition on Thermoelectric Properties of Polycrystalline CrSi2 Journal of Electronic Materials, 1042 42 (2013)
    9. Perumal.S, Gorsse S., Ail, U., Prakasam, M.,Chevalier, B., Umarji, A. M Thermoelectric properties of chromium disilicide prepared by mechanical alloying Journal of Materials Science, 6018 48 (2013)
    10. Srivastava Geetika, Goswami Ankur, Umarji, A. M.Temperature dependent structural and dielectric investigations of PbZr0.5Ti0.5O3 solid solution at the morphotropic phase boundary Ceramics International, 1977 39 (2013)

Conference proceedings

    1. Sherikar Baburao N.,Umarji, A. M.Synthesis of Diopside by Solution Combustion Process Using Glycine Fuel International Journal of Modern Physics: Conference Series, 217 22 (2013)

Career Publications:

    1. A.M.Umarji, C.S. Sunandana, G.V.S. Rao, Synthesis and electrical-properties of mixed tetrahedral cluster phases Fe(Mo2Re2)S8, Ni(Mo2Re2)S8, Zn(Mo2Re2)S8, Cu(Mo2Re2)S8 and Ge(Mo2Re2)S8,, Materials Research Bulletin.,1025 14 (1979)
    2. S. Vasudevan, C.N.R. Rao, A.M.Umarji, G.V.S. Rao, Studies on BiCoO3 and BiCo1-XFeXO3, Materials Research Bulletin, 451 14 (1979)
    3. A.M.Umarji, G.V.S. Rao, V. Sankaranarayanan, G. Rangarajan, R. Srinivasan, Synthesis and properties of o-containing chevrel phases, CoXMo6S6O2, NiXMo6S6O2, CuXMo6S6O2, and PbXMo6S6O2, Materials Research Bulletin, 1025 15 (1980)
    4. A.M.Umarji, G.V. Subbarao, M.P. Janawadkar, T.S. Radhakrishnan, Metal atom incorporation studies on AXMo6S8 chevrel phases, Journal of Physics and Chemistry of Solids, 421 41 (1980)
    5. S. Ramasamy, T. Nagarajan, A.M.Umarji, G.V.S. Rao, Electronic-properties of chevrel phases by positron angular-correlation, Physics Letters A, 7181 (1981)
    6. A.M.Umarji, G.V.S. Rao, M.P. Janawadkar, T.S. Radhakrishnan, Structure and superconductivity of PB1-XAXMo6.58 (A=Ag,In,Bi) chevrel phases, Solid State Communications, 137 (1981)
    7. S. Yashonath, M.S. Hegde, P.R. Sarode, C.N.R. Rao, A.M.Umarji, G.V.S. Rao, Charge-transfer in chevrel phases, Solid State Communications, 32537 (1981)
    8. V. Sankaranarayanan, G. Rangarajan, R. Srinivasan, A.M.Umarji, G.V.S. Rao, Electrical-resistivity and superconductivity in the chevrel phase-compounds of the type Cu1.8Mo6S8-ysey, (0 less-than-or-equal-to y less-than-or-equal-to 8) and Cu1.8Mo6S8-y tey, (0 less-than-or-equal-to y less-than-or-equal-to 4), Cryogenics, 305 22 (1982)
    9. D.R. Noakes, G.K. Shenoy, D. Niarchos, A.M.Umarji, A.T. Aldred, Magnetism and crystalline electric-fields in R2Fe3Si5 compounds, Physical Review B, 4317 27 (1983)
    10. D.R. Noakes, A.M.Umarji, G.K. Shenoy, Mossbauer studies of REFe2Si2 (RE=GD-LU) compounds, Journal of Magnetism and Magnetic Materials, 309 39 (1983)
    11. A.M.Umarji, D.R. Noakes, P.J. Viccaro, G.K. Shenoy, Rare-Earth And Fe-57 mossbauer studies in REFe2Si2 compounds, Journal of the Less-Common Metals, 265 94 (1983)
    12. A.M.Umarji, D.R. Noakes, P.J. Viccaro, G.K. Shenoy, A.T. Aldred, D. Niarchos, Magnetic-properties of REFe2Si2 compounds, Journal of Magnetism and Magnetic Materials, 61 36 (1983)
    13. R. Haushalter, C. Oconnor, A. Umarji, G. Shenoy, C. Saw, Synthesis of new amorphous metallic spin-glasses from the oxidation of zintl anions by transition-metal cations, Abstracts of Papers of the American Chemical Society, 235 187 (1984)
    14. R.C. Haushalter, C.J. Oconnor, A.M.Umarji, G.K. Shenoy, C.K. Saw, Spin-glass behavior in the new amorphous-alloys M2SNTe4 (M=Cr,Mn,Fe), Solid State Communications, 929 49 (1984)
    15. R.C. Haushalter, C.M. Oconnor, J.P. Haushalter, A.M.Umarji, G.K. Shenoy, synthesis of new amorphous metallic spin-glasses Cr2SNTe4, Mn2SNTe4, Fe2SNTe4, Co2SNTe4 – solvent induced metal-insulator transformations, Angewandte Chemie-International Edition in English, 169 23 (1984)
    16. J.C. Huffman, J.P. Haushalter, A.M.Umarji, G.K. Shenoy, R.C. Haushalter, Synthesis of tin tellurium polyanions – structure of (Me4N)4Sn2Te6, Inorganic Chemistry, 2312 23 (1984)
    17. D.R. Noakes, A.M.Umarji, G.K. Shenoy, D.G. Hinks, Orientation of gd moments in REXGd1-XRh4B4 (RE=Ho,Er), Journal of Applied Physics, 1847 55 (1984)
    18. C.J. Oconnor, R. Haushalter, G.K. Shenoy, A. Umarji, C. Saw, Spin-glass behavior in the amorphous metallic alloys M2SNTe4 (M=Cr,Mn,Fe), Abstracts of Papers of the American Chemical Society, 157187 (1984)
    19. G.K. Shenoy, D.G. Hinks, A.M.Umarji, C.W. Kimball, Confirmation of the oxygen defect in the chevrel-phase SnMo6S8 from Sn-119 mossbauer-spectroscopy, Solid State Communications, 62151 (1984)
    20. M.A. Subramanian, A. Clearfield, A.M.Umarji, G.K. Shenoy, G.V.S. Rao, Synthesis and solid-state studies on MB2Sb2O7 and (MN1-XCD*X)*2Sb*2O*7 pyrochlores, Journal of Solid State Chemistry, 12452 (1984)
    21. A.M.Umarji, G.K. Shenoy, D.R. Noakes, S. Dattagupta, Crystal fields and 2nd-order magnetic hyperfine interactions in TmFe*2Si*2, Journal of Applied Physics, 2297 55 (1984)
    22. K.S. Athreya, L.S. Hausermannberg, R.N. Shelton, S.K. Malik, A.M.Umarji, G.K. Shenoy, Superconductivity in the ternary borides CeOS3B2 AND CeRu3B2 – magnetic-susceptibility and specific-heat measurements, Physics Letters A, 330 113 (1985)
    23. H.A. Kierstead, B.D. Dunlap, S.K. Malik, A.M.Umarji, G.K. Shenoy, Coexistence of ordered magnetism and superconductivity in Pd2YbSN, Physical Review B, 13532 (1985)
    24. S.K. Malik, A.M.Umarji, G.K. Shenoy, Magnetic and mossbauer studies on GdCO3B2 and DyCO3B2, Journal of Applied Physics, 3252 57 (1985)
    25. S.K. Malik, A.M.Umarji, G.K. Shenoy, Depression of the superconducting transition-temperature of the heusler alloy Pd2YSN with the addition of magnetic rare-earth-metals, Physical Review B, 4426 32 (1985)
    26. S.K. Malik, A.M.Umarji, G.K. Shenoy, Magnetic and mossbauer studies on rare-earth-containing heusler alloys Pd2Tb-YBSN, Physical Review B, 697131 (1985)
    27. S.K. Malik, A.M.Umarji, G.K. Shenoy, A.T. Aldred, D.G. Niarchos, Magnetism and superconductivity in the system Ce1-XLaXRh3B2, Physical Review B, 4742 32 (1985)
    28. S.K. Malik, A.M.Umarji, G.K. Shenoy, T.A. Aldred, D.G. Niarchos, Magnetism in the system Ce1-XLaXRh3B2, Journal of Applied Physics, 304357 (1985)
    29. S.K. Malik, A.M.Umarji, G.K. Shenoy, P.A. Montano, M.E. Reeves, Valence state of Ce and the magnetism in CeRh3B2, Physical Review B, 472831 (1985)
    30. S.K. Malik, A.M.Umarji, G.K. Shenoy, M.E. Reeves, Moment collapse in the Ce(Rh1-XOSX)3B2 system, Solid State Communications, 761 54 (1985)
    31. A.M.Umarji, S.K. Malik, G.K. Shenoy, Effect of paramagnetic rare-earth ions on the superconducting transition-temperature of the heusler alloy Pd2YSN, Physica B & C, 423135 (1985)
    32. A.M.Umarji, S.K. Malik, G.K. Shenoy, Upper critical fields in Y2Fe3Si5, Sc2Fe3Si5, Lu2Fe3Si5 compounds, Journal of Applied Physics, 3118 57 (1985)
    33. A.M.Umarji, S.K. Malik, G.K. Shenoy, Superconductivity and magnetism in the pseudoternary system Tm1-XGdXRh4B4, Journal of Applied Physics, 312457 (1985)
    34. A.M.Umarji, S.K. Malik, G.K. Shenoy, Structural transformation studies on the rare-earth containing heusler alloys Pd2RESN, Solid State Communications, 1029 53 (1985)
    35. P.P. Vaishnava, C.W. Kimball, A.M.Umarji, S.K. Malik, G.K. Shenoy, Magnetic and mossbauer investigation of ErFe4B, TmFe4B, LuFe4B compounds, Journal of Applied Physics, 3264 57 (1985)
    36. P.P. Vaishnava, C.W. Kimball, A.M.Umarji, S.K. Malik, G.K. Shenoy, Fe-57 AND Er-166 mossbauer and magnetic studies of ErFe4B, TmFe4B, LuFe4B compounds, Journal of Magnetism and Magnetic Materials, 286 49 (1985)
    37. C. Godart, A.M.Umarji, L.C. Gupta, R. Vijayaraghavan, Magnetism and spin fluctuation effects in heavy-fermion CeRu2SI2 induced by partial substitution of Ru and Si, Physical Review B, 7733 34 (1986)
    38. S.K. Malik, A.M.Umarji, G.K. Shenoy, Field-induced reentrant superconductivity in the heusler alloy system Pd2Y1-XDyXSN, Physical Review B, 3144 34 (1986)
    39. S.K. Malik, A.M.Umarji, G.K. Shenoy, M.E. Reeves, Magnetic-behavior of transition-metal substituted CeRh3B2 – destabilization of the 4f moment, Journal of Magnetism and Magnetic Materials, 439 54-7 (1986)
    40. A.M.Umarji, C. Godart, L.C. Gupta, R. Vijayaraghavan, spin fluctuation effects in substituted CeRu2Si2and YBPd2Si2 alloys, Pramana, 32127 (1986)
    41. E.E. Alp, A.M.Umarji, S.K. Malik, G.K. Shenoy, M.Q. Huang, E.B. Boltich, W.E. Wallace, Fe-57 mossbauer studies on Si-substituted Er2Fe17, Journal of Magnetism and Magnetic Materials, 30568 (1987)
    42. C. Godart, A.M.Umarji, L.C. Gupta, R. Vijayaraghavan, Magnetism changes in ge and os substituted CeRu2Si2, Journal of Magnetism and Magnetic Materials, 32663-4 (1987)
    43. I.K. Gopalakrishnan, A.M.Umarji, J.V. Yakhmi, L.C. Gupta, R.M. Iyer, R. Vijayaraghavan, On the synthesis and superconducting properties of La1.8M0.2CuO4 systems, Materials Letters, 1655 (1987)
    44. I.K. Gopalakrishnan, J.V. Yakhmi, A.M.Umarji, L.C. Gupta, A.K. Rajarajan, R.M. Iyer, R. Vijayaraghavan, Studies on superconducting behavior of La2-XMXCuO4 (M = Ba, Sr, Ca), and the influence of some dopants, Phase Transitions, 193 10 (1987)
    45. S.K. Malik, C.V. Tomy, A.M.Umarji, D.T. Adroja, R. Prasad, N.C. Soni, A. Mohan, C.K. Gupta, Superconductivity in the Ag-substituted La1.8Sr0.2CuO4 oxide system, Journal of Physics C-Solid State Physics, L417 20 (1987)
    46. S.K. Malik, A.M.Umarji, D.T. Adroja, C.V. Tomy, R. Prasad, N.C. Soni, A. Mohan, C.K. Gupta, High-temperature superconductivity in the oxide system (Y1-XBaX)2CuO4(0.2-less-than-or-equal to-x-less-than-or-equal to-0.5), Journal of Physics C-Solid State Physics, L347 20 (1987)
    47. G.M. Phatak, A.M.Umarji, J.V. Yakhmi, L.C. Gupta, K. Gangadharan, R.M. Iyer, R. Vijayaraghavan, Superconductivity and localization in (La,Y)2-XSXCuO4, Solid State Communications, 905 63 (1987)
    48. R. Prasad, N.C. Soni, A. Mohan, C.K. Gupta, A.M.Umarji, D.T. Adroja, S.K. Malik, Superconductivity in the liquid-nitrogen temperature-range in the Y-Ba-Cu-O system, Materials Letters, 232 5 (1987)
    49. C.V. Tomy, A.M.Umarji, D.T. Adroja, S.K. Malik, R. Prasad, N.C. Soni, A. Mohan, C.K. Gupta, Superconductivity in Yba2(CU1-XAgX)3O7-delta oxide system, Solid State Communications, 889 64 (1987)
    50. A.M.Umarji, S.K. Dhar, S.K. Malik, R. Vijayaraghavan, evolution of magnetism from mixed-valent CeIr3B2 to trivalent CeIr3Si2, Physical Review B, 892936 (1987)
    51. A.M.Umarji, C. Godart, L.C. Gupta, R. Vijayaraghavan, Spin fluctuation changes in Ge doped YBPD2Si2, Journal of Magnetism and Magnetic Materials, 623 63-4 (1987)
    52. A.M.Umarji, I.K. Gopalakrishnan, J.V. Yakhmi, L.C. Gupta, R. Vijayaraghavan, R.M. Iyer, On the high tc-superconductivity in (Y1-XBaX)2CuO4-delta and La1.8Sr0.2CuO4,
    53. A.M.Umarji, K.S. Nanjundaswamy, Effect of nominal copper concentration in yba2cu3+/-xo7-delta on the superconducting transition, Pramana, L611 29 (1987)
    54. A.M.Umarji, J.V. Yakhmi, N. Nambudripad, R.M. Iyer, L.C. Gupta, R. Vijayaraghaven, Magnetic-properties of 2 new uranium-based alloys – UAuCu4 and UPdCu4, Journal of Physics F-Metal Physics, L25 17 (1987)
    55. J.V. Yakhmi, I.K. Gopalakrishnan, L.C. Gupta, A.M.Umarji, R. Vijayaraghavan, R.M. Iyer, bulk superconductivity at 36-K in La1.8Sr0.2CuO4, Physical Review B, 712235 (1987)
    56. J.V. Yakhmi, L.C. Gupta, I.K. Gopalakrishnan, A.M.Umarji, R.M. Iyer, R. Vijayaraghavan, High-tc superconductivity in La1.8M0.2CuO4 (M=Ca, Sr, Ba) and (Y1-XBaX)2cuo4,
    57. J.V. Yakhmi, R.M. Iyer, A.M.Umarji, A.K. Rajarajan, L.C. Gupta, R. Vijayaraghavan, Superconductivity characteristics of the system Y1.2Ba0.8CuO4-delta, Phase Transitions, 49 10 (1987)
    58. A.K. Ganguli, G.N. Subbanna, A.M.Umarji, S.V. Bhat, C.N.R. Rao, Superconductivity In The 100-120 K REGION IN OXIDES OF THE TL-CA-BA-CU-O SYSTEM, Pramana, L483 30 (1988)
    59. A.K. Ganguli, K.S.N. Swamy, G.N. Subbanna, A.M.Umarji, S.V. Bhat, C.N.R. Rao, Preparation, structure, microwave-absorption and other properties of the 125k superconductor Tl2Ca2Ba2Cu3O10+delta, Solid State Communications, 39 67 (1988)
    60. C.N.R. Rao, A.M.Umarji, R.A.M. Ram, R. Vijayaraghavan, K.S.N. Swamy, P. Somasundaram, L. Ganapathi, High-temperature superconductivity in bismuth-copper oxides of the type bimmgncupox, bimcancupox, bisrncupox, bimbacupox, bimbincupox, Pramana, L359 30 (1988)
    61. P. Somasundaram, K.S. Nanjundaswamy, A.M.Umarji, C.N.R. Rao, Structure and superconducting properties of YBa2-XLnXCu3O7+/-delta (Ln = La,Nd or Gd) and (Ln,Ln’) 3-XBa3+XCu6O14+delta, Materials Research Bulletin, 1139 23 (1988)
    62. A.M.Umarji, P. Somasundaram, L. Ganapathi, C.N.R. Rao, The Y3-XBa3+XCu6O14+delta system of superconductors, Solid State Communications, 177 66 (1988)
    63. A.M.Umarji, P. Somasundaram, C.N.R. Rao, Y3-XBa3+XCu6/14+delta System – a new family of superconductors, Physica C, 497153 (1988)
    64. S. Senbhagaraman, T.N.G. Row, A.M.Umarji, Corrected spacegroup for M0.5Ti2P3O12 compounds, Solid State Communications, 60971 (1989)
    65. C.N.R. Rao, R. Nagarajan, R. Vijayaraghavan, N.Y. Vasanthacharya, G.V. Kulkarni, G.R. Rao, A.M.Umarji, P. Somasundaram, G.N. Subbanna, A.R. Raju, A.K. Sood, N. Chandrabhas, superconducting cuprates of the series Bi2Ca1-XRare-EarthXSr2Cu2O8+delta, Bi2Ca1-XYXSr2Cu2O8+delta, Superconductor Science & Technology, 242 3 (1990)
    66. S. Senbhagaraman, A.M.Umarji, Effect of cation valence on thermal-expansion of NaTi2P3O12, CA5Ti2P3O12, LA033Ti2P3O12 compounds, Journal of Solid State Chemistry, 169 85 (1990)
    67. P. Somasundaram, A.M. Ram, A.M.Umarji, C.N.R. Rao, Synthesis and characterization of superconducting YbBa2Cu3O7-delta and Y1-XLuXBa2Cu3O7-delta (0.0 less-than x less-than 0.75) – lower limit of the rare-earth ion radius tolerated in the 123-cuprate system, Materials Research Bulletin, 331 25 (1990)
    68. P. Somasundaram, A.M.Umarji, Effect of sb substitution on the superconductivity of Bi2(Ca,Sr)N+1Cu1O4N+2, Bi2(Ca,Sr)N+1CU2O4N+2, BI2(CA,SR)N+1CU3O4N+2, Pramana-Journal of Physics, 369 35 (1990)
    69. P. Somasundaram, R. Vijayaraghavan, R. Nagarajan, R. Seshadri, A.M.Umarji, C.N.R. Rao, Occurrence of maximum tc at an optimal carrier concentration in superconducting bismuth and thallium cuprates, Applied Physics Letters, 487 56 (1990)
    70. A.M.Umarji, Chemical stabilization of 123 phase in the In-Ba-Cu-O system,
    71. S.A.S. Asif, P. Somasundaram, A.M.Umarji, S.K. Biswas, Effect of lanthanum substitution at the barium site on the mechanical-behavior in ybco superconductor, Materials Research Bulletin, 7328 (1993)
    72. S. Senbhagaraman, T.N.G. Row, A.M.Umarji, Structural refinement using high-resolution powder x-ray-diffraction data of ca0.5ti2p3o12, a low-thermal-expansion material, Journal of Materials Chemistry, 309 3 (1993)
    73. P. Somasundaram, A.M.Umarji, Structural and physical characterization of Bi2Ca1-XLnXSr2Cu2O8+delta (Ln=Dy or Y) glasses, Physica C, 393 209 (1993)
    74. S. Vepa, A.M.Umarji, Effect of substitution of Ca on thermal-expansion of cordierite (Mg2Al4Si5O18), Journal of the American Ceramic Society, 187376 (1993)
    75. M.V.R. Rao, A.M.Umarji, Thermal-expansion studies in lead iron niobate lead-zinc niobate and related systems, Materials Research Bulletin, 1031 30 (1995)
    76. N.N. Sampathkumar, A.M.Umarji, B.K. Chandrasekhar, Synthesis of alpha-cordierite (indialite) from fly-ash, Materials Research Bulletin, 1107 30 (1995)
    77. V. Sunder, A. Halliyal, A.M.Umarji, Investigation of tetragonal distortion in the PbTiO3 BiFeO3 system by high-temperature x-ray-diffraction,
    78. V. Sunder, A.M.Umarji, Thermal-expansion studies in the lead iron niobiate – lead titanate system, Materials Research Bulletin, 427 30 (1995)
    79. R. Kadirvelraj, A.M.Umarji, W.T. Robinson, S. Bhattacharya, T.N.G. Row, Systematic crystallographic investigation of hydrogen-bonded networks involving monohydrogen tartrate-amine complexes: Potential materials for nonlinear optics, Chemistry of Materials, 23138 (1996)
    80. M. Muthuraman, K.C. Patil, S. Senbagaraman, A.M.Umarji, Sintering, microstructural and dilatometric studies of combustion synthesized synroc phases, Materials Research Bulletin, 1375 31 (1996)
    81. S.K. Ramasesha, M.V.R. Rao, A.K. Singh, A.M.Umarji, Lowering of relaxor transition temperature in lead-based perovskites under pressure, Materials Research Bulletin, 1141 31 (1996)
    82. R.M.V. Rao, A. Halliyal, A.M.Umarji, Perovskite phase formation in the relaxor system Pb(Fe1/2Nb1/2)O-3 (1-x)- Pb(Zn1/3Nb2/3)O-3 (x), Journal of the American Ceramic Society, 257 79 (1996)
    83. M.V.R. Rao, A.M.Umarji, Thermal expansion studies on ferroelectric materials, Bulletin of Materials Science, 1023 20 (1997)
    84. M.V.R. Rao, A.M.Umarji, Y. Kumar, K.K. Jain, E.S. Rajagopal, Effect of high pressure on the dielectric properties of relaxor compositions Pb(Fe1/2Nb1/2)O-3 (1-x-y)- Pb(Zn1/3Nb2/3)O-3 (x)- BaTiO3 (y), Journal of Materials Science Letters, 121 16 (1997)
    85. T. Dasgupta, A.M.Umarji, Thermal properties of MoSi2 with minor aluminum substitutions, Intermetallics, 128 15 (2007)
    86. T. Dasgupta, U.V. Waghmare, A.M.Umarji, Electronic signatures of ductility and brittleness, Physical Review B, 76 (2007)
    87. J. De, A.M.Umarji, K. Chattopadhyay, Origin of contamination and role of mechanochemistry during mechanical alloying: the case of Ag-Te alloys,1062 Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing, ,b449 (2007)
    88. S. Sumithra, U.V. Waghmare, A.M.Umarji, Anomalous dynamical charges, phonons, and the origin of negative thermal expansion in Y2W3O12, Physical Review B, 76 (2007)
    89. T. Dasgupta, J. Etourneau, B. Chevalier, S.F. Matar, A.M.Umarji, Structural, thermal, and electrical properties of CrSi2, Journal of Applied Physics, 103 (2008)
    90. T. Dasgupta, S. Sumithra, A.M.Umarji, A novel method to control oxygen stoichiometry and thermoelectric properties in (RE)BaCo2O5+delta, 859 Bulletin of Materials Science, 31 (2008)
    91. T. Dasgupta, A.M.Umarji, Role of milling parameters and impurity on the thermoelectric properties of mechanically alloyed chromium silicide, 292 Journal of Alloys and Compounds, 461 (2008) 292
    92. T. Dasgupta, A.M.Umarji, Improved ductility and oxidation resistance in Nb and Al co-substituted MOSi2, 739 Intermetallics, 16 (2008)
    93. G.V. Kunte, S.A. Shivashankar, A.M.Umarji, Humidity sensing characteristics of hydrotungstite thin films, 835 Bulletin of Materials Science, 31 (2008)
    94. G.V. Kunte, S.A. Shivashankar, A.M.Umarji, Thermal analysis and vapour pressure of a new series of tungsten(VI) oxo-alkoxide-beta-ketoesterate complex precursors for the chemical vapour deposition of tungsten oxide, 12 Thermochimica Acta, 474 (2008) 12
    95. G.V. Kunte, S.A. Shivashankar, A.M.Umarji, Thermogravimetric evaluation of the suitability of precursors for MOCVD, Measurement Science & Technology, 19 (2008)
    96. A. Gairola, G.V. Kunte, A.M.Umarji, S.A. Shivashankar, Determination of the enthalpies of sublimation and evaporation from thermogravimetric data: Application to metalorganic complexes of Al and Cr, 17 Thermochimica Acta, 488 (2009)
    97. A. Gairola, A.M.Umarji, S.A. Shivashankar, Microwave irradiation assisted method for the rapid synthesis of fine particles of alpha Al2O3 and alpha (Al1-XCrx)2O3 and their coatings on si(100), in: N.P. Bansal, J.P. Singh (Eds.) 15 Processing and Properties of Advanced Ceramics and Composites, 2009
    98. P. Jaiswal, G.V. Kunte, A.M.Umarji, S.A. Shivashankar, Ellipsometric study of Atomic Layer Deposited TiO2 thin films, in: M.R. Singh, R.H. Lipson (Eds.) 396 Transport and Optical Properties of Nanomaterials, 2009
    99. S.R. Varanasi, P. Kumar, V.R. Puranik, A. Umarji, S. Yashonath, Structure, energetics and diffusion properties of isomers of trimethyl benzene in beta zeolite: Uptake and Monte Carlo simulation study, 135 Microporous and Mesoporous Materials, 125 (2009)
    100. A. Gairola, G.V. Kunte, D. Chopra, T.N.G. Row, A.M.Umarji, S.A. Shivashankar, Synthesis and characterization of metal substituted AlxCr1-x(acetylacetonate)3 single-source precursors for their application to MOCVD of thin films, 2680 Polyhedron, 29 (2010)
    101. Geetika, A.M.Umarji, The influence of Zr/Ti content on the morphotropic phase boundary in the PZT-PZN system, 171 Materials Science and Engineering B-Advanced Functional Solid-State Materials, 167 (2010)
    102. A. Goswami, A.M.Umarji, G. Madras, Degradation Kinetics of Poly(HDDA-co-MMA), 2444 Journal of Applied Polymer Science, 117 (2010)
    103. S. Gorsse, P. Bellanger, Y. Brechet, E. Sellier, A. Umarji, U. Ail, R. Decourt, Nanostructuration via solid state transformation as a strategy for improving the thermoelectric efficiency of PbTe alloys, 7425 Acta Materialia, 59 (2011)
    104. A. Goswami, A. Phani, A. Krisna, N. Balashanmugam, G. Madras, A.M.Umarji, Poly-HDDA microstructure fabrication using Microstereolithography for Micro-cantilever based sensor technology, 7926 Micromachining and Microfabrication Process Technology Xvi, (2011)
    105. G.V. Kunte, U. Ail, P.K. Ajikumar, A.K. Tyagi, S.A. Shivashankar, A.M.Umarji, Estimation of vapour pressure and partial pressure of subliming compounds by low-pressure thermogravimetry, 1633 Bulletin of Materials Science, 34 (2011)
    106. B.N. Sherikar, A.M.Umarji, Effect of Adiabatic Flame Temperature on Nano Alumina Powders during Solution Combustion Process, 167 Transactions of the Indian Ceramic Society, 70 (2011)
    107. P. Suresh, A.M.Umarji, Thermoelectric Properties of Nano Structured CrSi2-xAlx, in: A.B. Garg, R. Mittal, R. Mukhopadhyay (Eds.) 429 Solid State Physics: Proceedings of the 55th Dae Solid State Physics Symposium 2010, Pts a and B, 2011
    108. A. Goswami, A. Phani, A.M.Umarji, G. Madras, Polymer microfabrication by scanning based microstereolithography: Optical design and material functionality, Review of Scientific Instruments, 83 (2012)
    109. A. Goswami, G. Srivastava, A.M.Umarji, G. Madras, Thermal degradation kinetics of poly(trimethylol propane triacrylate)/poly(hexane diol diacrylate) interpenetrating polymer network, 53 Thermochimica Acta, 547 (2012)
    110. A. Goswami, A.M.Umarji, G. Madras, Thermomechanical and fractographic behavior of poly (HDDA-co-MMA): a study for its application in microcantilever sensors, 1604 Polymers for Advanced Technologies, 23 (2012)
    111. G. Srivastava, M. Maglione, A.M.Umarji, The study of dielectric, pyroelectric and piezoelectric properties on hot pressed PZT-PMN systems, Aip Advances, 2 (2012)
    112. S.I.M. Umarji, M.W.T. Arnander, D.M. Evans, The use of Swanson silastic interposition arthroplasty in revision thumb-base surgery for failed trapeziectomy; a case series of 10 patients, 632 Journal of Hand Surgery-European Volume, 37E (2012)
    113. B. Angadi, M.R. Ajith, A.M.Umarji, Synthesis, microstructure and thermal expansion studies on CaO center dot 5+x/2SrO center dot 5+x/2Zr4P6-2x Si-2x O-24 system prepared by co-precipitation method, 87 Bulletin of Materials Science, 36 (2013)
    114. A. Goswami, A.M.Umarji, G. Madras, Study of Thermal Relaxation of Poly (HDDA-co-MMA) by Temperature Modulated DSC and Dielectric Spectroscopy, 485 Polymer-Plastics Technology and Engineering, 52 (2013)
    115. V.B. Kamble, S.V. Bhat, A.M.Umarji, Investigating thermal stability of structural defects and its effect on d(0) ferromagnetism in undoped SnO2, Journal of Applied Physics, 113 (2013)
    116. V.B. Kamble, A.M.Umarji, Defect induced optical bandgap narrowing in undoped SnO2 nanocrystals, Aip Advances, 3 (2013)
    117. V.B. Kamble, A.M.Umarji, Gas sensing response analysis of p-type porous chromium oxide thin films, 8167 Journal of Materials Chemistry C, 1 (2013)
    118. S. Perumal, S. Gorsse, U. Ail, B. Chevalier, R. Decourt, A.M.Umarji, Effect of co-substitution of Mn and Al on thermoelectric properties of chromium disilicide, 227 Journal of Materials Science, 48 (2013)
    119. S. Perumal, S. Gorsse, U. Ail, R. Decourt, A.M.Umarji, Effect of Composition on Thermoelectric Properties of Polycrystalline CrSi2, 1042 Journal of Electronic Materials, 42 (2013)
    120. S. Perumal, S. Gorsse, U. Ail, M. Prakasam, B. Chevalier, A.M.Umarji, Thermoelectric properties of chromium disilicide prepared by mechanical alloying, 6018 Journal of Materials Science, 48 (2013)
    121. G. Srivastava, A. Goswami, A.M.Umarji, Temperature dependent structural and dielectric investigations of PbZr0.5Ti0.5O3 solid solution at the morphotropic phase boundary, 19776 Ceramics International, 39 (2013)
    122. A. Goswami, K. Ankit, N. Balashanmugam, A.M.Umarji, G. Madras, Optimization of rheological properties of photopolymerizable alumina suspensions for ceramic microstereolithography, 3655 Ceramics International, 40 (2014)