Online Thesis Search Results

TITLE
CERTIFICATE
DECLARATION
ACKNOWLEDGEMENT
Preface
CONTENTS
PART I
1. GENERAL INTRODUCTION AND EXISTING INFORMATION OF RARE EARTH MIXED CRYSTALS OF BARIUM MOLYBDATES AND COPPER OXALATES
1.1 Introduction
1.2 Mixed crystals of rare earth barium molybdates
1.2.1 Existing information on molybdates
1.2.2 Chemistry of molybdates
1.2.3 Structure and symmetry
1.2.4 Properties
1.2.5 Habits
1.3 Mixed crystals of rare earth copper oxalates
1.3.1. Existing information on oxalates
1.3.2. Chemistry of oxalates
1.3.3. Structure and symmetry
1.3.4. Properties
1.3.5. Habits
2. CRYSTAL GROWTH IN GELS
2.1. Introduction
2.2. Existing growth procedures - a review
2.3. Different types of gel and structure of silica hydrogel
2.4. Growth characteristics in gel
3. EXPERIMENTAL TECHNIQUES
3.1. Introduction
3.2. silvering technique
3.3. Optical microscopy
3.4. Scanning electron microscopy
3.5. X-ray diffractometry
3.6. Etching technique
3.7. Infrared spectroscopy
3.8. Energy dispersive analysis of X-rays
3.9. Laser Raman spectroscopy
3.10. u-v-visible - near infrared spectroscopy
3.11. Thermal analyses
3.12. XRF analysis
3.13. ICP analysis
PART II
4. GROWTH KINETICS AND CHARACTERIZATION OF SAMARIUM BARIUM MOLYBDATE MIXED CRYSTALS IN SILICA GEL
4.1. Introduction
4.2. Experimental
4.2.1. Single diffusion experiments
4.2.2. Double diffusion experiments
4.3. Observations
4.3.1. Growth of samarium barium molybdate mixed crystals
4.3.2. Effect of variation in the concentration of top solution
Table 4.1 EXPERDENTAL CONDITIONS EQR THE CRYSTALLIZATION OFSAMARIUM BARIUM MOLYBDATE CRYSTALS IN SILICA GEL
Table 4.2 EXPERIMENTAL CONDITIONS FOR THE CRYSTALLIZATION OFSAMARIUM BARIUM MOLYBDATE CRYSTALS IN SILICA GEL
Fig. 4.3 Effect of concentration on therate of displacewnt ofprecipitate front.
Fig. 4.4. Effect of concentration on the rate of disaolntionfmnt.
4.3.3. Effect of pH variation on precipitation and dissolution rates
Fig.4.5 Effect of pH of gel on precipitation front movements
Fig. 4.6 Effect of pH of gel on dissolution frontmovements
4.3.4. Liesegang ring formation
4.3.5. Morphology of the crystals
Fig. Captions
PLATE I
4.4. Characterization
4.4.1. Chemical analysis
4.4.2. X-ray analysis
Table 4.3 X-RAY POWDER DATA
Fig. 4.11 XRD diffraction pattern of samarium barium molybdatemixed crystal.
4.4.3. IR analysis
4.4.4. Laser Raman spectra analysis
Fig. 4.12. Infrared spectrum of samarium barium molybdatemixed crystal.
Fig.4.13. Laser Raman spectrum of samarium barium molybdate mixed crystal
4.4.5. uv-visible - near infrared analysis
4.4.6. Thermal analyses
Fig. 4.14 W-visible-near infrared spectrumof samarium barium molybdatemixed crystal.
4.4.7. EDAX
Fig.4.15 TGA plot of samarium barium molybdate mixed crystal
Fig.4.16 DSC plot of the mixed crystal samarium barium molybdate
Fig. 4.17 EDAX pattern of samarium barium molybdatemixed crystal
Table 4.4 RESULTS OF EDAX
4.4.8. XRF analysis
Fig. 4.18. XRF plot of the samarium bariummolybdate mixed crystal.
4.5. Conclusion
5. OBSERVATIONS ON THE GROWTH AND CHARACTERIZATION OF MIXED CRYSTALS OF NEODYMIUM BARIUM MOLYBDATE
5.1. Introduction
5.2. Experimental
5.3. Growth procedure
5.3.1. Effect due to change in concentration of the nutrients
Table 5.1 Experimental Conditions for the Growth of Neodymium BariumMolybdate Crystals in Gel
Fig. 5.3 Rate of displacements of precipitation anddissolution fronts due to the change in theouter electrolyte (pa = 8)
Fig. 5.4 Rate of displacements of preaipitatim anddoiustseorl eulteicotnr forloynttes (dpuHe = t S
5.3.2. Effect due to change in pH of the gel
Fig. 5.5 Square of length versus t i m e of growthof g e l grown b i p y r d d a l octahedralcrystals for different outer electrolyteconcentation.
Fig. 5.6 plot showing time-displac-t ofand partial dissolutionftonts due to change in PH of ae gel
5.3.3. Morphology of the crystals
5.4. Characterization
5.4.1. X-ray analysis
Fig. Captions
PLATE II
5.4.2. IR analysis
Fig. 5.13 XRD pattern of neodymium barium molybdate mixed crystal
Table 5.2 X-RAY POWDER DATA
Fig. 5.14 Infrared spectrum of neodymium barium molybdate mixed crystal
5.4.3. Laser Raman spectra analysis
5.4.4. uv-visible -near infrared analysis
5.4.5. EDAX
Fig. 5.15. Raman spectrum of neodynium barium molybdate mixed crystal (Range: 30- 1300 cm-1)
Fig.5.16. Raman spectrum of neodymium barium molybdate mixed crystal (Range: 1400- 2600) cm-1
Fig.5.17. uv-visible-near infrared absorption spectrum of neodymium barium molybdate crystal.
5.4.6. XRF analysis
Fig.5.18 EDAX pattern of neodymium barium molybdate mixed crystal
Fig. 5.19. XRF spectrum of the neodymiumbarium molybdate mixed c r y s t a
5.4.7. Thermal analyses
5.5. Conclusion
Fig.5.20. TGA plot of neodymium barium molybdate mixed crystal
Fig. 5.21. DTA plot of neodymium barium molybdate mixed crystal
6. GROWTH, CHARACTERIZATION AND IDENTIFICATION OF GEL GROWN PRASEODYMIUM BARIUM MOLYBDATE MIXED CRYSTALS
6.1. Introduction
6.2. Growth procedure
6.3. Discussion
6.3.1. Effect of density of gel
6.3.2. Effect of variation in the concentration of inner and outer electrolytes
Fig. 6.l (a) The effect of variationof the outer electrolyteon precipitation front.
Fig. 6. l (b) The effect of variationof the outer electrolyteon dissolution front.
6.3.3. Effect of variation in the pH of gels
6.3.4. Liesegang ring formation
6.4. Morphology of the crystals
Table 6.1EXPERIMENTAL CONDITIONS FOR THE GROWTH OF PRASEODYMIUMBARIUM MOLYBDATE CRYSTALS IN GEL
Fig. Captions
PLATE III
6.5. Characterization
6.5.1. Chemical analysis
6.5.2. XRD analysis
Table 6.2 X-RAY DATA
Fig.6.12 X-ray diffraction pattern of praseodymium barium molybdate mixed crystal
6.5.3. IR analysis
Fig.6.13. Infrared spectrum of praseodymium barium molybdate mixed crystal
6.5.4. Laser Raman spectra analysis
6.5.5. Spectrophotographic (uv-visible – near infrared) analysis
Fig.6.14 Raman spectrum of praseodymium barium molybdate mixed crystal
Fig. 6.15. uv-visible-near infrared spectrum of praseodymiumbarium molybdate mixed crystal. (Range: 200-300 and 400-500)
6.5.6. EDAX analysis
Table 6.3 EDAX DATA
Fig.6.16 EDAX pattern of praseodymium barium molybdate mixed crystal
6.5.7. XRF analysis
6.5.8. Thermal analyses
Fig. 6.17. XRF spectrum of the praseodymiumbarium molybdate mixed crystal.
Fig. 6.18 TGA plot of praseodymium barium molybdate mixed crystal
Fig.6.19 DSC plot of praseodymium barium molybdate mixed crystal
6.6 Conclusion
7. RARE EARTH (Sm, Nd, Pr) MIXED BARIUM MOLYBDATE SINGLE CRYSTALS - IN GENERAL
7.1. Introduction
7.2. Discussion
7.2.1. Growth and effect of different parameters on the growth of the crystals
7.2.2. Morphology
7.2.3. Identification and characterization
Table 7.1-1SPECTRA DATA (~ n) A ND BAND ASSIGNMENTS OF MIXED CRYSTALSOF RARE EARTB (Sm, Nd 6 Pr) BARIUM MOLYBDATE
7.3. Conclusion
PART III
8. GROWTH AND CHARACTERIZATION OF MIXED CRYSTALS OF SAMARIUM COPPER OXALATE IN SILICA GEL
8.1 Introdction
8.2. Experimental
8.2.1. Single diffusion process
8.2.2. Double diffusion process
8.3 Observations
8.3.1. Growth of samarium copper oxalate crystals
8.3.2. Effect of variation in the concentration of outer electrolyte
8.3.3. Effect of pH variation of gels
Fig. 8.3 The effect of concentrationof outer electrolyte on therate of displacement ofprecipitation front andcryetallization region
Fig.8.4 Variation in depth ofprecipitation and regionof crystallization withrespect to change in pHvalue of the gel.
Table 8.1EXPERIMENTAL GROWTH CONDITIONS OFSAHARIUM COPPER OXALATE MIXED CRYSTALS
8.3.4. Liesegang ring formation
8.3.5. Morphology
8.3.6. Spherulitic formation
8.3.7. Etching
Fig. Captions
PLATE IV
8.4. Characterization
8.4.1. Chemical analysis
FIGURB CAPTIONS
PLATE V
8.4.2. X-ray analysis
8.4.3. IR analysis
Fig.8.15 X-ray diffraction pattern of samarium copper oxalate mixed crystal
Table 8.2.X-RAY m E R DATA
Fig.8.16 Infrared spectrum of samarium copper oxalate mixed crystal
8.4.4. Laser Raman spectra analysis
Fig. 8.17. Raman spectrum of safarium copper oxalate mixed crystal (Range: 50-2000 cm-)
Fig.8.18 Raman spectrum of samarium copper oxalate mixed crystal
8.4.5. uv-visible -near infrared analysis
8.4.6. EDAX
Fig. 8.19. uv-visible-near infrared spectrum of the samariumcopper oxalate mixed crystal.
Table 8.3 EDAX RESULTS
Fig. 8.20 EDAX pattern of the spherulite samarium copperoxalate.
8.4.7. XRF analysis
8.4.8. Thermal analyses
Fig. 8.21. XRF plot of samarium copper oxalate mixed crystal
Fig.8.22 TGA plot of the mixed crystal samarium copper oxalate
8.5 Conclusion
Fig. 8.23 DSC plot of samarium copper oxalate mixed crystal.
9. GROWTH KINETICS AND CHARACTERIZATION OF NEODYMIUM COPPER OXALATE MIXED CRYSTALS
9.1 Introduction
9.2 Growth procedure
Table 9.1 EXPERIMENTAL CONDITIONS FOR CRYSTALLIZATION OF NEODYMIUMCOPPER OXALATE MIXED CRYSTALS
9.3 Observations
9.3.1. Effect of variation in the concentration of outer electrolyte
9.3.2. Effect of pH variation of gels
Fig.9.3 Variation in the depth of precipitation and crystallisation region with respect to concentration of outer electrolyte (pH =7)
Fig.9.4 Variation in the depth of precipitation and crystallisation region with respect to concentration of outer electrolyte (pH = 8)
Fig. 9.5 Variation in the depth of precipitationand crystallization region with respectto the pHofthe gel
9.3.3. Morphology of the crystals
Fig. Captions
PLATE VI
9.4 Characterization
9.4.1. Chemical analysis
9.4.2. XRD analysis
Fig. Captions
PLATE VII
9.4.3. IR analysis
Fig.9.14 XRD pattern of neodymium copper oxalate mixed crystal
Table 9.2 XRD DATA OF NEODYMIUM COPPER OXALATE
Fig.9.15. Infrared absorption spectrum of Neodymium copper oxalate mixed crystal
9.4.4. Laser Raman spectra analysis
Fig. 9.16. Raman spectrum of neodymium copper oxalate mixed crystal (100-2500 cm-1
Fig.9.17.Raman spectrum of neodymium copper oxalate mixed crystal (2500-3600 cm-1)
9.4.5. uv-visible-near infrared analysis
9.4.6. EDAX visible
Fig. 9.18. uv-visible-near infrared spectrum of themixed crystal neodymium co er oxalate (Range: 200-280 and 400-60 8
Fig. 9.19 EDAX pattern of neodymium copper oxalatemixed crystal.
Table 9.3EDAX DATA OF NEODYMIUM COPPER OXALATE MIXED CRYSTAL
9.4.7. ICP analysis
9.4.8. XRF analysis
9.4.9. Thermal analyses
Fig 9.20 XRF spectrum of neodymium copper oxalate mixed crystal
Fig.9.21. TGA plot of the mixed crystal neodymium copper oxalate
Fig.9.22 DSC plot of neodymiunm copper oxalate mixed crystal
9.5 Conclusion
10. OBSERVATIONS ON THE GROWTH AND CHARACTERIZATION OF PRASEODYMIUM COPPER OXALATE MIXED CRYSTALS
10.1 Introduction
10.2 Growth procedure
10.3 Observations
10.3.1 Effect of variation in the concentration of outer electrolyte
10.3.2 Effect of pH variation of gels
Table 10.1EXPERIMENTAL CONDITIONS FOR CRYSTALLIZATION OFPRESEODYMIUM COPPER OXALATE MIXED CRYSTALS
Fig.10.1 Effect of variation of the outer electrolyte on depthof precipitation and crystallizationregion (pH=
Fig. 10.2 Effect of variation of theouter electrolyte on depthof precipitation and cry- -stallization region (pH=7)
10.3.3 Morphology of the crystals
Fig.10.3 Effect of pH on precipitation and crystallization front movements.
Fig. Captions
PLATE VIII
10.4 Characterization
10.4.1 Chemical analysis
10.4.2 XRD analysis
Fig.10.13 XRD pattern of praseodymium copper oxalate crystal
Table 10.2 XRD DATA OF PRASEODYMIUM COPPER OXALATE MIXED CRYSTAL
10.4.3 IR analysis
Fig.10.14 Infrared absorption spectrum of praseodymium copper oxalate mixed crystal.
10.4.4 Laser Raman spectra analysis
10.4.5 UV-visible-near infrared analysis
10.4.6 EDAX
Fig.lO.17 uv-visible-near infrared spectrumof praseodymium coppcr oxa laLemixed crystal (Range: 200-500)
10.4.7 ICP analysis
Fig. 10.18 (a) EDAX pattern ofpraseodymium copperoxalate mixed crystal
Fig. 10.18 (b) . 10.18 (a) of range7-10 KEV magnified.
10.4.8 XRP analysis
10.4.9 Thermal analyses
Fig 10.19. XRF spectrum of praseodymiumcopper oxalate mixed crystal.
Fig.10.20 TGA plot of the mixed crystal praseodymium copper oxalate
10.5 Conclusion
Fig. 10.21. DTA plot of praseodymium copper oxalate mixed crystal
11. RARE EARTH (Sm, Nd, Pr) COPPER OXALATE MIXED CRYSTALS A GENERAL DISCUSSION
11.1 Introduction
11.2 Discussion
11.2 1 Growth effects
11.2.2 Morphology
Schematic diagram showing differentzones of crystallization.
Voids in the crystals
Spherulites
Etching
11.2 3 Characterization
Table 11.1 ASSIGNMENTS OF IR AND RAMAN BAND FREQUENCIES (cm
11.3 Conclusion
11.4 Scope of the work
APPENDIX LIESEGANG RING PHENOMENA DURING THE GROWTH OF RARE EARTH BARIUM MOLYBDATE MIXED CRYSTALS
a.1. Introduction
a.2. Pattern of rings
a.3. Factors related to Liesegang ring formation
a.4. Theories of Liesegang phenomena
a.5. Experimental
a.6. Effect of various parameters
a.6.1 Variation of outer electrolyte
a.6.2 Variation of inner electrolyte
a.6.3 pH variation of gel medium
Fig. Captions
PLATE IX
a.7. Experimental verification
a.7.1 Relation between diffusion depth (x) and the width of rings (AX)
a.7.2 Effect of ageing
a.8. Discussion
Table - a.1 VARIATION OF Δx WITH x (FOR pH = 5) Outer electrolytes - IM neodymium nitrate + cupric nitrate, Inner electrolyte - 1Sstandard solution.
Table- a.2 VARIATION OF Δx WITH x (FOR pH =4)
Fig. (a) Effect of pH on ring spacing
a.9. Conclusion
References