Nanostructured, electroactive and bioapplicable materials

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auxiliary organics, aging conditions and template removal method. 32,33,52 The wall thickness, which greatly affects the thermal stability of the material, is controlled by the charge of the surfactant and the formation mechanism. Materials prepared with neutral surfactants usually exhibit a greater wall thickness and furthermore a higher thermal stability than that obtained with ionic surfactants, due to the absence of electrostatic or charge-matching effects. 37 1.4. Mesoporous Materials from Nonsurfactant Templated Sol-Gel Methods A novel nonsurfactant templated sol-gel route to mesoporous materials has been developed by our group. 53,54 Unlike the surfactant template pathway, the non-surfactant organic compounds, such as glucose, maltose, and dibenzoyltartaric acid, were employed as templates or pore structure directing agents during a sol-gel process under room temperature. The template can be easily removed by solvent extraction. The obtained materials exhibit mesoporosity with pore diameter of ~2-6 nm, which is controllable by simply varying the nonsurfactant content in the solution. The materials show high surface area of ~1000 m 2 g -1 and large pore volume of ~1.0 cm 3 g -1 . The pore structure is not highly ordered, which is similar to that of some neutral surfactant templated mesoporous materials. A framework filled with interconnected wormlike pores is observed. The initial study of the nonsurfactant template pathway involved the formation of silica mesophases under acidic conditions. Subsequent efforts have shown these structures can also be formed in basic or near neutral media. 53 13
The mechanism of nonsurfactant templating to mesophase formation was not yet fully understood. It was proposed that during the nonsurfactant templated sol-gel process, nonsurfactant aggregates and the aggregate assemblies may function as the organic templates. The interactions between the organic templates and the silicate intermediates, such as hydrogen bonding, may also play an important role in directing the mesophase formation prior to and/or during the gelation. Through the nonsurfactant templated sol-gel pathway, mesoporous silica oxide, alumina oxide and titanium oxide have been successfully prepared. 55 Mesoporous zinc phosphate has been obtained with the glucosamine molecules as nonsurfactant template. 56 The process has been extended to prepare various advanced materials including organic- inorganic hybrid materials 57 and mesoporous bio-composites with enzyme/protein immobilized. 14 In comparison to the surfactant templated sol-gel method to mesoporous materials, the nonsurfactant templated pathway is mild, less expensive, environmentally friendly and biofriendly. In this method, easy removal of template by solvent extraction can avoid the structure damage by calcination. The framework thickness from the non-surfactant route (~4 nm) is much larger than that of M41S (0.8-1.5 nm), which contributes to superior thermal stability. Porous silica by the non-surfactant route exhibits much fewer defects than that from neutral surfactants. Moreover, a vast diversity of organic compounds provides possibilities to form macroscopic nanostructured sol-gel materials. 14
Page 1: Nanostructured, Electroactive and B
Page 4 and 5: Dedications This dissertation is de
Page 6 and 7: School of Biomedical Engineering, S
Page 8 and 9: 2.2. Experimental .................
Page 10 and 11: 5.2.2. Treatment of Substrate Surfa
Page 12 and 13: 8.2. Electroactive, Bioapplicable M
Page 14 and 15: List of Tables Table 2-1. Compositi
Page 16 and 17: Figure 2-9. BJH pore size distribut
Page 18 and 19: xvi pattern of gold nanoparticles i
Page 20 and 21: xviii PANI under culturing conditio
Page 22 and 23: Figure B-8. Cyclic voltammogram (Pt
Page 24: The resultant polyaniline-collagen
Page 27 and 28: Chapter 2 presents a study focused
Page 29 and 30: Chapter 7 is focused on the synthes
Page 31 and 32: surfactant templated method was ext
Page 33 and 34: The porous structure of the silica
Page 35 and 36: Before early 1990s, with a pore or
Page 37: − Neutral surfactants: the hydrop
Page 41 and 42: zero in a pore. Structural informat
Page 43 and 44: 1.5.1. Gas Sorption Measurement As
Page 45 and 46: which is usually associated with ca
Page 47 and 48: 16. Iler, R. K. The Chemistry of Si
Page 49 and 50: 52. Sayari, A.; Danumah, C.; Moudra
Page 51 and 52: Figure 1-1. Three structure types p
Page 53 and 54: Figure 1-3. IUPAC classification of
Page 55 and 56: Chapter 2. Mesoporous Sol-Gel Mater
Page 57 and 58: well formed below the isoelectric p
Page 59 and 60: 2.1.2. Nonsurfactant Templates and
Page 61 and 62: since controllable partial removal
Page 63 and 64: were ground manually into fine powd
Page 65 and 66: volatile sol-gel reaction byproduct
Page 67 and 68: After the thermal treatment at 150
Page 69 and 70: oiling point of benzoin (i.e., 194
Page 71 and 72: interconnected pores or channels wi
Page 73 and 74: 6. Huo, Q.; Magargolese, D. I.; Cie
Page 75 and 76: Table 2-1. Composition and pore par
Page 77 and 78: Weight (%) 100 80 60 40 20 0 0 100
Page 79 and 80: Weight (%) 100 90 80 70 60 0 100 20
Page 81 and 82: Weight (%) 100 90 80 70 60 50 40 0
Page 83 and 84: Figure 2-7. Representative IR spect
Page 85 and 86: dV/dD Pore Volume (cm 3 g -1 Å -1
Page 87 and 88: dv/dD, Pore Volume (cm 3 g -1 Å -1
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Net Pore Volume (cm 3 g -1 ) 0.6 0.
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Chapter 3. Synthesis of Mesoporous
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preparation conditions. In general,
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cubic, as well as vesicular structu
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3.2 Experimental The synthesis appr
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3.2.3. Synthesis of Mesoporous Sphe
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fructose is incorporated into the s
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mainly attributed to the monolayer-
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with nonsurfactant templates at dif
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3.4. Conclusions and Remarks In the
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11. Matijević, E.; Gheradi, P. Tra
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41. Polarz, S.; Smarsly, B.; Bronst
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(a) (b) Figure 3-1. Typical SEM ima
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Volume Adsorbed (cm 3 g -1 , STP) 3
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Figure 3-5. Representative TEM imag
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(a) (b) Figure 3-7. Typical SEM ima
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Chapter 4. Synthesis of Mesoporous
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nm, and the reaction reaches the hi
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microemulsion. 39 Martino et al. re
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the colloidal gold sol was combined
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holders with adhesive carbon tape.
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trapped in the gold-silica matrix,
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108 The Barrett-Joyner-Halenda (BJH
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indicative of a well-defined crysta
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(i.e., 2-50 nm). Combining both hig
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19. Hayashi, T.; Tanaka, K.; Haruta
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53. Qi, L.; Ma, J.; Cheng, H.; Zhao
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Figure 4-1. Representative X-ray en
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Pore Volume (cm 3 g -1 A -1 ) 0.06
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(a) (b) 122 Figure 4-5. (a) Represe
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Absorbance Wavelength (nm) Figure 4
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5.1.1. Organic-Inorganic Nanocompos
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128 We are also interested in the p
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mica and graphite, the top layer wa
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mode. Scanning electron microscopy
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Waal’s forces), the agglomeration
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136 A single glass transition tempe
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5.5. Acknowledgments 138 I want to
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30. Dimitrov, A. S.; Nagayama, K. L
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(a) (b) 142 Figure 5-2. Representat
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144 Figure 5-4. Representative AFM
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Figure 5-6. Representative IR spect
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(a) (b) Figure 5-8. Representative
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the possibility of utilizing conduc
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iocompatibility and water solubilit
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emeraldine salt, the unique conduct
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acid (HCl, 37.3%, Fisher), hydrogen
Page 183 and 184:
the surface of polymer coated cultu
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acidic acid aqueous solution showed
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oxidant, indicating the formation o
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complex was synthesized by pre-alig
Page 191 and 192:
8. Epstein, A. J. Springer Ser. Mat
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45. Liu, J.-M.; Yang, S. Chem. Comm
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Figure 6-1. Schematics of biologica
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172 Figure 6-3. UV-Vis absorption s
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Figure 6-5. FT-IR spectra of (a) co
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176 Figure 6-7. UV-Vis absorption s
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(a) (b) 178 Figure 6-9. Comparison
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prepared and purified as substitute
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greatest advantages of organic mate
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een explored as a direct and effect
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if we could fine-tune the carrier t
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NMR (250 MHz, DCCl3) δ (ppm): 8.95
Page 215 and 216:
7.2.4. Instrumentation and Characte
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The absence of the proton from the
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194 The absorbance at 600 nm is the
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L3Al dissociated to free ligand (L)
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198 State and Integrated Circuit Te
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34. Stossel, M.; Staudigel, J.; Ste
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Table 7-1. The UV absorbance at 600
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Figure 7-2. Schematic cross-section
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Figure 7-4. NMR Spectra of ligand 1
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Figure 7-6. FT-IR spectra of (a) li
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Figure 7-8. During air oxidation: 1
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[A] 1.2E-04 1.0E-04 8.0E-05 6.0E-05
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Figure 7-12. Mass spectrum of alumi
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Chapter 8. Concluding Remarks 216 T
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218 In contrast to the conventional
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properties of gold nanoparticles ma
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222 In an effort to obtain new elec
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as sensor units, the biodegradable
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polyanhydrides, 4 polyorthoesters,
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substitution reaction, several hund
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polyphosphazenes. Obtained material
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polyphosphazene network. Studies in
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matrix is readily formed due to the
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236 The delivery system can be made
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phosphazene main chains. Further in
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9. Allcock, H. R. Adv. Mater. 1994,
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Figure A-1. Repeating unit in polyp
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Figure A-3. Applications of materia
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Figure A-5. Preparation of poly(N-i
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B.3. Acknowledgments 248 I am grate
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Figure B-2. Cyclic voltammogram (Hg
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Figure B-4. Cyclic voltammogram (Pt
Page 279 and 280:
Figure B-6. Cyclic voltammogram (Hg
Page 281 and 282:
Figure B-8. Cyclic voltammogram (Pt
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