Relevant bibliographies by topics / Hot Stage Optical Microscopy

Academic literature on the topic 'Hot Stage Optical Microscopy'

Author: Grafiati
Published: 4 June 2021
Last updated: 9 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Contents

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Hot Stage Optical Microscopy.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Hot Stage Optical Microscopy"

1

Maeda, Yoji, and Mitsuo Koizumi. "New high‐pressure hot stage for optical microscopy." Review of Scientific Instruments 67, no. 5 (May 1996): 2030–31. http://dx.doi.org/10.1063/1.1146965.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Tick, P. A., K. E. Lu, S. Mitachi, T. Kanamori, and S. Takahashi. "Hot stage optical microscopy studies of crystallization in fluoride glass melts." Journal of Non-Crystalline Solids 140 (January 1992): 275–80. http://dx.doi.org/10.1016/s0022-3093(05)80781-1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Lu, Q. M., and M. Libera. "Microstructural measurements of amorphous GeTe crystallization by hot‐stage optical microscopy." Journal of Applied Physics 77, no. 2 (January 15, 1995): 517–21. http://dx.doi.org/10.1063/1.359034.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Ji, Ze Sheng, Sumio Sugiyama, and Jun Yanagimoto. "Microstructure Changes in Alloy AZ31B in Semisolid State and Its Mechanical Properties." Solid State Phenomena 116-117 (October 2006): 159–62. http://dx.doi.org/10.4028/www.scientific.net/ssp.116-117.159.

Full text
Abstract:
The structural changes of the wrought magnesium alloy AZ31B in semisolid state were clarified using optical microscopy and hot-stage microscopy. The influence of heat treatment variables was assessed. Compression tests covering a range from room temperature to 673 K were carried out for mechanical property assessment; flow stress and breaking strain were determined. The following are the results: (1) The grain growth of the hot-extruded AZ31B without preprocessing sensitively reacted at temperature and retention time. (2) The hot-extruded AZ31B with 30 % preprocessing showed an almost perfectly spheroidized structure in a semisolid state under certain conditions. (3) Heating velocity markedly affected the spheroidizing rate of grains. (4) From the direct observation of the hot-extruded alloy AZ31B by hot-stage microscopy, spheroidization was observed in some crystal populations. (5) Spheroided materials in the semisolid temperature range had a lower flow stress and a larger breaking strain than nonspheroidized materials. These results indicate the possibility of manufacturing wrought magnesium alloy by cold working.
APA, Harvard, Vancouver, ISO, and other styles
5

Zhang, Bo Hou, Bo Long Li, Peng Qi, Ning Li, Tong Bo Wang, and Zuo Ren Nie. "Mechanical Behavior and Microstructure of Hot Deformation of with Er 7N01 Aluminum Alloy." Materials Science Forum 993 (May 2020): 294–98. http://dx.doi.org/10.4028/www.scientific.net/msf.993.294.

Full text
Abstract:
In this paper, an Al-Zn-Mg-Cu alloy with a small amount of Er and Zr added was used as the research object. The homogenization annealing was carried out, and the 7N01 aluminum alloy was used at 300 °C, 350 °C, 400 °C, 450 °C and 0.1 s-1, 1 s-1, 10 s-1 deformation conditions by Gleeble-3500 thermal simulator. Optical Microscopy (OM), Scanning Electron Microscopy (SEM), Electron Backscatter Diffraction (EBSD) and Transmission Electron Microscopy (TEM) were used for microstructure analysis. The results show that the stress-strain curve of with Er 7N01 aluminum alloy can be divided into micro-strain stage, uniform deformation stage and steady-state flow stage during the thermal compression process. The flow stress of 7N01 aluminum alloy achieved peaks at the initial stage of strain, and then increased with the increase of strain rate and the decrease of deformation temperature. With the increase of deformation temperature and the decrease of deformation rate, the recrystallization process was significantly increased.
APA, Harvard, Vancouver, ISO, and other styles
6

Kobayashi, Sengo, Kiyomichi Nakai, and Yasuya Ohmori. "Analysis of Phase Transformation in a Ti-10 mass%Zr Alloy by Hot Stage Optical Microscopy." MATERIALS TRANSACTIONS 42, no. 11 (2001): 2398–405. http://dx.doi.org/10.2320/matertrans.42.2398.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Enose, Arno A., Priya K. Dasan, H. Sivaramakrishnan, and Sanket M. Shah. "Formulation and Characterization of Solid Dispersion Prepared by Hot Melt Mixing: A Fast Screening Approach for Polymer Selection." Journal of Pharmaceutics 2014 (March 12, 2014): 1–13. http://dx.doi.org/10.1155/2014/105382.

Full text
Abstract:
Solid dispersion is molecular dispersion of drug in a polymer matrix which leads to improved solubility and hence better bioavailability. Solvent evaporation technique was employed to prepare films of different combinations of polymers, plasticizer, and a modal drug sulindac to narrow down on a few polymer-plasticizer-sulindac combinations. The sulindac-polymer-plasticizer combination that was stable with good film forming properties was processed by hot melt mixing, a technique close to hot melt extrusion, to predict its behavior in a hot melt extrusion process. Hot melt mixing is not a substitute to hot melt extrusion but is an aid in predicting the formation of molecularly dispersed form of a given set of drug-polymer-plasticizer combination in a hot melt extrusion process. The formulations were characterized by advanced techniques like optical microscopy, differential scanning calorimetry, hot stage microscopy, dynamic vapor sorption, and X-ray diffraction. Subsequently, the best drug-polymer-plasticizer combination obtained by hot melt mixing was subjected to hot melt extrusion process to validate the usefulness of hot melt mixing as a predictive tool in hot melt extrusion process.
APA, Harvard, Vancouver, ISO, and other styles
8

Han, P. D., A. Asthana, Z. Xu, and D. A. Payne. "Growth twins in Bi2Ca1Sr2Cu2O8 superconductor single crystals." Journal of Materials Research 5, no. 5 (May 1990): 909–12. http://dx.doi.org/10.1557/jmr.1990.0909.

Full text
Abstract:
Large-scale twin structures in single crystal Bi2Ca1Sr2Cu2O8 (2122) are reported for the first time. Symmetrical 90° (i.e., a-b) twins with a [110] type twin boundary were observed. A characteristic layer-growth morphology and jagged twin walls suggest that twin formation occurred layer by layer during crystal growth; i.e., the twins were growth twins. Hot-stage optical microscopy, x-ray diffraction, and electron microscopy results are discussed with reference to twin morphology.
APA, Harvard, Vancouver, ISO, and other styles
9

Smith, Ronald W. "The Staining of Polymers." Microscopy Today 10, no. 5 (September 2002): 5–7. http://dx.doi.org/10.1017/s1551929500058272.

Full text
Abstract:
In the beginning there was water-the first stain that delineated structure within a polymeric system. The polymerwas natural rubber (NR) and the system was an air-dried film of natural latex. Grenquist reported in 1929 that a dried film of natural rubber latex soaked in hot water became milky (Figure 1) and, at that stage, the latex particles could be detected by the optical microscope (OM), The contrast mechanism was provided by the absorption of water by the naturally occurring proteinaceous layers present on the congealed NR particle surfaces. There was little demand for polymer staining until the age of electron microscopy.
APA, Harvard, Vancouver, ISO, and other styles
10

Journal, Baghdad Science. "Liquid crystalline dendrimer: Sythesis and Chracterization." Baghdad Science Journal 11, no. 2 (June 1, 2014): 491–501. http://dx.doi.org/10.21123/bsj.11.2.491-501.

Full text
Abstract:
A new family of nematic liquid crystal dendrimers derived from 3,5-dihydroxybenzoic acid were synthesized. The synthesis of the dendrimers compounds shows the influence of the dendritic core on the mesomorphic properties. The liquid crystalline properties were studied by polarizing optical microscopy (POM) equipped with a hot stage, the structures of the synthesized compounds characterized using FTIR and 1HNMR spectroscopy.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Hot Stage Optical Microscopy"

1

Lele, Stephen, and slele@bigpond net au. "Additives on the Curing of Phenolic Novolak Composites." RMIT University. Applied Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070205.095402.

Full text
Abstract:
The research programme studied the cure reaction of a phenolic novolak resin and the effects of various additives and fillers on the reaction. The programme utilised the recently developed thermal analysis technique of temperature-modulated differential scanning calorimetry (TMDSC) performed in conjunction with other available thermal analysis techniques. TMDSC enables the signal for the heat of reaction to be separated from the underlying specific heat change in the resin. This meant that the reaction could be studied without interference from any physical changes in the resin. The manufacture of composite brake materials required the use of numerous additives and fillers to produce the desired properties. The influence of such additives on the cure rate and final properties of the resin was known to occur but had not previously been measured due to the difficulties presented by the presence of opaque additives. Some additives also underwent thermally induced physical changes in the temperature range of the cure. The final properties and the processing of new brake materials undergoing development often required trial and error adjustments to compensate for changes in cure rate. An understanding of the influence of additives would enable more rapid commercial development of brake materials through an improvement in the ability to predict both the properties of the product and the optimal processing parameters. Processing efficiency could also be improved through detailed knowledge of the kinetics. Moulding cycle times and post-baking times and temperatures were longer than necessary in order to ensure adequate cure at the end of each stage because of the lack of kinetic data. The cure of phenolic resin has been shown to be highly complicated with numerous alternate and competing reactions. For the manufacture of composite materials, knowledge of the kinetic parameters of individual reactions is not considered to be important; rather the overall kinetic parameters are required for prediction. Therefore the kinetic model parameters that best described the observed behaviour were chosen even though the model had no basis in the molecular interaction theory of reaction. Rather it served as a convenient tool for predictions. Characterisation of the resin proved to be difficult due to the presence of overlapping peaks, and volatile reaction products. TMDSC was successfully used to determine the reaction kinetics of the pure resin and the influence of certain additives on the reaction kinetics. The determination of the kinetic parameters using TMDSC agreed well with the traditional Differential Scanning Calorimetry isothermal and non-isothermal techniques. Both the Perkin-Elmer and TA Instruments were utilised for the research and were found to provide reasonably good agreement with each other. The capabilities and limitations of the individual instruments were critically examined, frequently beyond the manufacturers' specifications. TMDSC suffers from a limitation in the heating rate of the sample compared to DSC. However, it was observed that valuable information could still be obtained from TMDSC despite using heating rates that were higher than specified by manufacturers. Hot Stage Microscopy and thermogravimetry were additional experimental techniques used to aid in the characterisation of the resin. Some inhomogeneity of the resin was identified as well as differences in the behaviour of the cure between open (constant pressure) and closed (constant volume) environments were observed. A novel method of determining the orders of the cure reactions and their kinetic parameters was utilised. Reaction models for the overall cure reactions were postulated and tested by fitment to sections of experimental data in temperature regions which appeared to be free of interference from overlapping peaks. Once an individual peak was reasonably well modelled, adjacent overlapping peaks were able to be modelled both individually and in combinations by fitment to experimental data. The Solver function in Microsoft Excel was utilised to find the best fitting model parameters for the experimental data. The model parameters were able to be refined as overlapping peaks were progressively incorporated into the calculations. This method produced results that agreed well with the traditional method of analysing reaction peak temperatures at multiple scanning rates. Model fitment was shown to be of benefit where overlapping reactions occur. Various model scenarios could be tested and optimised to particular sections of experimental data. This enabled the researcher to easily identify areas of possible anomalies and postulate alternative scenarios. The accuracy of the postulated model was able to be determined by its successful fitment to experimental data from experiments run under different conditions.
APA, Harvard, Vancouver, ISO, and other styles
2

Rafieda, Ali Mohamed Omar. "Efavirenz pre-formulation study : selection of a cyclodextrin inclusion complex or co-crystal complex for tabletting." Thesis, University of the Western Cape, 2015. http://hdl.handle.net/11394/5186.

Full text
Abstract:
>Magister Scientiae - MSc
Efavirenz is a non-nucleoside reverse transcriptase inhibitor used as an anti-retroviral for the treatment of human immunodeficiency virus (HIV) type I. It is classified as a class IΙ drug under the Biopharmaceutical Classification System (BCS) and exhibits a low solubility (aqueous solubility of 9.0 μg/ml) and high permeability (variable oral bioavailability). This study aims to choose a pre-formulation protocol with the best efavirenz derivative in literature between co-crystals and CD inclusion complexes. Upon selection of the efavirenz derivative, the complications of both small scale and large scale laboratory pre-formulation production is highlighted for formulation of a tablet dosage form. Numerous variables were selected for the pre-formulation protocol. Physical, chemical, pharmacological, pharmaceutical and economical variables were investigated. Citric acid monohydrate (CTRC) was chosen as the best co-former for a co-crystal while hydroxypropyl-beta-cyclodextrin (HP-β-CD) was selected as a host for an inclusion complex. Pharmaceutically, the angle of repose, Carr’s index, Hausner’s ratio, moisture content, disintegration time, hardness/resistance to crush, manufacturing process problems and particle size of the CTRC and HP-β-CD were all evaluated. The CTRC was ultimately selected for formulation of a tablet. The preparation of small laboratory scale of EFA/CTRC co-crystal was successfully achieved after several attempts. The large laboratory scale of EFA/CTRC was prepared under various environmental seasons which were indicated as batches 1-6 for purposes of this study. Characterization of the large laboratory scale EFA/CTRC co-crystals was performed by scanning electron microscopy (SEM), hot-stage microscopy (HSM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and by physical inspection (i.e. season, texture, colour, shape and particle size) of the EFA/CTRC product. Batch 1 and 2 were prepared during the summer season. The SEM analysis showed that the particles were needle-like shaped. The thermal analysis values of batch 1 by HSM, DSC and TGA results were 123 °C, 119 °C and 1.68 % of mass loss, respectively. In batch 2, morphology results by SEM revealed spikes of irregular and agglomerated particles. Batch 2 melted at 123 °C and a small unmelted quantity was observed at 143 °C. The DSC and TGA (mass loss) analysis were 118 °C and 0.75 % respectively. The hardness test of EFA/CTRC tablet prepared in batch 2 was extremely hard hence failed the disintegration test. The EFA/CTRC prepared in batches 3, 4 and 5 was during the winter season which is associated with high humidity and wet weather conditions. The SEM, DSC, TGA results were significantly different from the previous batches. The SEM morphology was highly irregular particles for batch 3, clustered and randomly size particle for batch 4 and irregular, needle-like, spikes and spherical shaped particles for batch 5, respectively. The thermal results HSM, DSC and TGA confirmed the presence of moisture in the prepared EFA/CTRC products. The HSM melting point results of batches 3, 4 and 5 were 123 °C, 115 °C and 121 °C, respectively. The DSC results of 110 °C, 105 °C and 118 °C were observed for batches 3, 4 and 5 respectively. The mass loss i.e. TGA results for batches 3, 4 and 5 were 1.178%, 1.5 % and 2.235 % respectively. In batch 6, EFA/CTRC was prepared using a different commercial batch of EFA and CTRC. The SEM results indicated the formation of needle-like and clustered particles. The values obtained from HSM, DSC and TGA results were 124 °C, 114 °C and 0.54 % in mass loss. The physical appearance of EFA/CTRC prepared from batch 1 and 2 were white in colour while batch 3, 4, 5 and 6 of the prepared EFA/CTRC was pink in colour. The physical appearance of the individual batches differed but the identity of the sample remained intact implying the same pharmacological effects with differing pharmaceutical properties impacting the dosage form preparation.
APA, Harvard, Vancouver, ISO, and other styles
3

Nalagatla, Dinesh Reddy. "INFLUENCE OF SURFACE ROUGHNESS OF COPPER SUBSTRATE ON WETTING BEHAVIOR OF MOLTEN SOLDER ALLOYS." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/488.

Full text
Abstract:
The objective of this study is to understand the effect of surface roughness of the Cu substrate on the wetting of molten solder alloys. Eutectic Sn-Pb, pure Sn and eutectic Sn-Cu solder alloys and Cu substrates with different surface finish viz., highly polished surface, polished surface and unpolished surface were used in this work. Highly polished surface was prepared in Metallography lab, University of Kentucky while other two substrates were obtained from a vendor. Surface roughness properties of each substrate were measured using an optical profilometer. Highly polished surface was found to be of least surface roughness, while unpolished surface was the roughest. Hot-stage microscopy experiments were conducted to promote the wetting behavior of each solder on different Cu substrates. Still digital images extracted from the movies of spreading recorded during hot-stage experiments were analyzed and data was used to generate the plots of relative area of spread of solder versus time. The study of plots showed that surface roughness of the Cu substrate had major influence on spreading characteristics of eutectic Sn-Pb solder alloy. Solder showed better spreading on the Cu substrate with least surface roughness than the substrates with more roughness. No significant influence of surface roughness was observed on the wetting behavior of lead free solders (pure Sn and eutectic Sn-Cu).
APA, Harvard, Vancouver, ISO, and other styles
4

Narayanaswamy, Ramnath. "INFLUENCE OF FLUX DEPOSITION NON-UNIFORMITY ON MOLTEN METAL SPREADING IN ALUMINUM JOINING BY BRAZING." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/376.

Full text
Abstract:
The objective of this thesis is to study the effects of flux deposition non uniformity on spreading of molten metal. Flux deposition non-uniformity here means as to whether the amount of flux deposited in a non-uniform or uniform pattern helps in the better wetting and spreading characteristics of the molten metal or is detrimental to the process. The material selection constraint to the study was imposed by selecting brazing of aluminum i.e., aluminum alloy melting and flow over an aluminum alloy substrate. The study was carried out by conducting a number of Hot Stage microscopy tests using aluminum silicon alloy as the filler metal and Potassium Fluoro Aluminate (Nocolok) as the flux. The flux was applied in different spatial distribution patterns to uncover the varying effects of its distribution on spreading. The uneven pattern of flux deposition indicates the influence on spreading but due to the efficient spreading of flux prior to aluminum melting and associated fuzziness of the achieved coverage distribution the effects are not always conclusive. It has been concluded that non uniform flux deposition does not necessarily mean uneven or less uniform spreading of the molten liquid metal if the spreading of the molten flux is beyond the distance of ultimate metal spreading. This is because, in spite of uneven flux deposition, the flux melts approximately at 560C-570C and spreads on the surface of the metal thereby promoting appreciable spreading and wetting of the molten liquid metal that happens at temperatures above 577C.
APA, Harvard, Vancouver, ISO, and other styles
5

Chan, Hin Chung Stephen. "Co-crystal screening of poorly water-soluble active pharmaceutical ingredients. Application of hot stage microscopy on curcumin-nicotinamide system and construction of ternary phase diagram of fenbufen-nicotinamide-water co-crystal system." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4253.

Full text
Abstract:
Curcumin is the major phenolic diarylheptane derivative in Curcuma longa and has been reported to possess pharmacological activities. Unfortunately this compound suffers from poor bioavailability and rapid neutral-alkaline degradation. Co-crystal of curcumin is one option under exploration, motivated by the fact that a number of active pharmaceutical ingredient (API) co-crystals with improved dissolution have recently been synthesized. Hence, co-crystallization technique highlights an alternative means to improve the performance of curcumin. Within our work evidences for a co-crystal was ascertained from DSC, Kofler hot stage screening and PXRD, and all confirmed a new crystal phase could have been formed between curcumin and a co-crystallizing agent, nicotinamide. We report that re-crystallization step essentially aids the purification of commercial curcumin, a herbal based actives. Otherwise the prevalence of a new crystal phase in solvent-mediated co-crystallization will be significantly reduced. Besides, phase diagram is an effective tool for the study of solubility behaviours in co-crystal system. In order to acquire related techniques, fenbufen, a poorly water soluble drug, was selected. The result showed the huge difference in solubility between fenbufen and nicotinamide lead to difficulty in the construction of phase diagram.
APA, Harvard, Vancouver, ISO, and other styles
6

Huang, Kuo Chih, and 黃國誌. "Modification of the Micro Hot Stage for Optical Microscopy." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/23399719813043662290.

Full text
Abstract:
碩士
國立勤益科技大學
機械工程系
101
Along with the developmental trends of tiny and thin products, the applied materials and elements are also smaller and thinner. The thermal properties and the reaction to the temperature of those materials and elements usually affect the product performance, so microscopic heating chamber plays an important role on researching the reactions from the micro test pieces to heat and temperature. If the microscopic heater is coupled with the other test instruments, the real-time test will be more functional. By placing the microscopic heater onto an optical microscope and processing the test, for an instance, we can study the effects of micro piece under different temperatures and time at high temperature. Now there are various microscopic heating chambers with specific function on the market; however, there are more improved spaces on how to take and load the micro test piece more conveniently onto the heating chamber and keeping the robustness and stability under operating the microscopic heating chamber. The purpose of this paper is to achieve easier take and load micro test piece after modifying the current microscopic heating chamber (Linkam TS1500) in the laboratory with micro test piece holder under the same original functions of heating oven. After modifying the settings, this paper will be the base for reference in the future for using the thermocouple measurer and far infrared ray thermal image instrument to measure the temperature distribution of microscopic heaters. This paper also shows the operation convenience of the modified microscopic heating chamber when integrated with the probe station from this laboratory for processing the experiment.
APA, Harvard, Vancouver, ISO, and other styles
7

(8782151), Joshua Trevett Dean. "The Kinetics of Thermal Decomposition and Hot-Stage Microscopy of Selected Energetic Cocrystals." Thesis, 2020.

Find full text
Abstract:

The thermal decomposition of four energetic cocrystals composed of 4-amino-3,5-dinitropyrazole (ADNP)/diaminofurazan (DAF), 2,4,6-trinitrotoluene (TNT)/ 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL20), 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX)/CL20, and 1-methyl-3,5-dinitro-1,2,4-triazole (MDNT)/CL20 were studied using simultaneous differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), and hot-stage microscopy. The kinetic parameters of their thermal decomposition reaction were determined using the Kissinger and Ozawa kinetic analysis methods. Each cocrystal’s peak exothermic temperature (decomposition temperature), activation energy, and pre-exponential constant are reported. Furthermore, these parameters from each cocrystal were compared to the same parameters from the corresponding stoichiometric physical mixture in order to identify changes in behavior attributable to the cocrystallization process. For ADNP/DAF, the cocrystal shows an 8% increase in the peak exotherm temperature and a 11-13% decrease in peak activation energy as compared to its physical mixture. For TNT/CL20, this comparison shows a much smaller change in the peak exotherm temperature (<1%) but shows a 5% decrease in activation energy. This cocrystal also experiences phase stabilization—where a phase transition of one or both coformers is omitted from the decomposition process. The HMX/CL20 cocrystal shows a 1% change in the peak exotherm temperature and shows a 2% increase in activation energy. Finally, for MDNT/CL20, this comparison shows nearly a 4% increase and a drastic decrease in peak activation energy by 42-44%. Cocrystallization clearly affects the thermal decomposition and reaction kinetics of these materials, offering the potential to create a hybrid-class of energetic materials which combines the high performance of an energetic material with the safety and insensitivity of another.

APA, Harvard, Vancouver, ISO, and other styles
8

Berry, David J., Colin C. Seaton, W. Clegg, R. W. Harrington, S. J. Coles, P. N. Horton, M. B. Hursthouse, et al. "Applying hot-stage microscopy to co-crystal screening: A study of nicotinamide with seven active pharmaceutical ingredients." 2008. http://hdl.handle.net/10454/4846.

Full text
Abstract:
no
Co-crystal screening is routinely undertaken using high-throughput solution growth. We report a low- to medium throughput approach, encompassing both a melt and solution crystallization step as a route to the identification of co-crystals. Prior to solution studies, a melt growth step was included utilizing the Kofler mixed fusion method. This method allowed elucidation of the thermodynamic landscape within the binary phase diagram and was found to increase overall screening efficiency. The pharmaceutically acceptable adduct nicotinamide was selected and screened against a small set of active pharmaceutical ingredients (APIs) (ibuprofen (both the racemic compound (R/S) and S-enantiomer), fenbufen, flurbiprofen (R/S), ketoprofen (R/S), paracetamol, piracetam, and salicylic acid) as part of a larger systematic study of synthon stability. From the screen, three new co-crystal systems have been identified (ibuprofen (R/S and S) and salicylic acid) and their crystal structures determined. Because of poor crystal growth synchrotron radiation was required for structure solution of the S-ibuprofen nicotinamide co-crystal. Two further potential systems have also been discovered (fenbufen and flurbiprofen), but crystals suitable for structure determination have yet to be obtained. A greater ability to control crystallization kinetics is required to yield phase-pure single-crystalline material for full verification of this crystal engineering strategy.
APA, Harvard, Vancouver, ISO, and other styles
9

(8774588), Spencer A. Fehlberg. "Decomposition of ammonium perchlorate encapsulated nanoscale and micron-scale catalyst particles." Thesis, 2020.

Find full text
Abstract:

Iron oxide is the most common catalyst in solid rocket propellant. We have previously demonstrated increased performance of propellant by encapsulating iron oxide particles within ammonium perchlorate (AP), but only nanoscale particles were used, and encapsulation was only accomplished in fine AP (~20 microns in diameter). In this study, we extended the size of particle inclusions to micron-scale within the AP particles as well the particle sizes of the AP-encapsulated catalyst particles (100s of microns) using fractional crystallization techniques with the AP-encapsulated particles as nucleation sites for precipitation. Here we report catalyst particle inclusions of micron-scale, as well as nanoscale, within AP and present characterization of this encapsulation. Encapsulating micron-sized particles and growing these composite particles could pave the way for numerous possible applications. A study of the thermal degradation of these AP-encapsulated particles compared against a standard mixture of iron oxide and AP showed that AP-encapsulated micron-scale catalyst particles exhibited similar behavior to AP-encapsulated nanoscale particles. Using computed tomography, we found that catalyst particles were dispersed throughout the interior of coarse AP-encapsulated micron-scale catalyst particles and decomposition was induced within these particles around catalyst-rich regions.

APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Hot Stage Optical Microscopy"

1

Denny, Lisa R., and Raymond F. Boyer. "Hot Stage Microscopy of Polystyrene and Polystyrene Derivatives." In Order in the Amorphous “State” of Polymers, 251–61. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4613-1867-5_10.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Earl, David A., and Mushtaq Ahmed. "Characterization of Glaze Melting Behavior with Hot Stage Microscopy." In Whitewares and Materials: Ceramic Engineering and Science Proceedings, Volume 24, Issue 2, 3–12. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2008. http://dx.doi.org/10.1002/9780470294796.ch1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Bernstein, Joel. "Analytical techniques for studying and characterizing polymorphs and polymorphic transitions." In Polymorphism in Molecular Crystals, 136–214. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780199655441.003.0004.

Full text
Abstract:
Chapter 4 deals with the analytical methods for the characterization of solid forms, including optical and hot stage microscopy, thermal methods (differential scanning calorimetry, thermal gravimetric analysis, etc.), X-ray diffraction methods (powder and single crystal methods), infrared and Raman spectroscopy, solid state nuclear magnetic resonance spectroscopy, electron microscopy, atomic force microscopy, scanning tunneling microscopy, and pycnometry (density measurements). The principles of each of these techniques are outlined, followed by representative examples of their application in the investigation and characterization of polymorphic systems. The integration of a number of analytical tools—“hyphenated techniques”—into a particular instrument is described for a number of cases, followed by a discussion of the experimental approach for determining if two samples comprise polymorphs of the same compound.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Hot Stage Optical Microscopy"

1

Hyatt, Calvin V., Shannon P. Farrell, Bob Armstrong, J. C. Bennett, Irv Keough, Gary Fisher, Jian Chen, and Michael A. Gharghouri. "Comparison of martensite transformation temperatures in a NiMnGa alloy determined with hot/cold stage optical microscopy and differential scanning calorimetry." In Smart Structures and Materials, edited by Dimitris C. Lagoudas. SPIE, 2003. http://dx.doi.org/10.1117/12.484741.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Shejale, Girish M. "Metallurgical Evaluation and Condition Assessment of FSX 414 Nozzle Segments in Gas Turbines by Metallographic Methods." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22542.

Full text
Abstract:
Gas turbine components such as nozzle segments, buckets, transition pieces and combustion liners experience damages such as creep, fatigue, high temperature oxidation and corrosion. The reliability, availability and efficiency of high temperature gas turbine parts is based on condition assessment and remaining life analysis. These gas turbine components are normally repaired, refurbished after stipulated operating hours. The decision on the extent of repairs is based on various inspection stages. Among various methodologies of condition assessment, metallography followed by microscopic evaluation has gained wide acceptance since it is cost effective, quick and reliable. Extensive in-house efforts have been put forth in this field in the development of improved techniques of metallography for accurate determination of material degradation and condition assessment. Experimental studies on Frame 6, 1st Stage Nozzle Segment (FSX 414 – cobalt based alloy) were conducted to assess the condition of the nozzle segment by using laboratory electropolishing technique for metallographic preparation. Sections taken from the nozzle segment were electropolished and examined in Light Optical Microscope (LOM) and Scanning Electron Microscope (SEM). It is concluded that the improved electropolishing technique is effective in assessing creep-fatigue, thermal fatigue and hot corrosion damage. Based on this the condition of the nozzle segment is assessed. Typical results of Frame 6, 1st Stage Nozzle Segment are presented and discussed.
APA, Harvard, Vancouver, ISO, and other styles
3

Miglietti, Warren, and John Scheibel. "Evaluation of Platform Weld Repairs on F-Class, Stage 1 Buckets." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14344.

Full text
Abstract:
Abstract The higher turbine inlet temperatures coupled with dry low emission combustors on the widely used F-class gas turbines produces high heat loadings on the stage 1, hot section components, particularly focused on the platform section of rotating buckets/blades. This paper provides a brief design and durability history overview of the platform areas of buckets. High heat loadings combined with cyclic operation, and variation in casting supplier quality, resulted in various levels of extensive cracking and high scrap rates based on prior conservative repair limits. Currently, the consensus amongst repair shops is that platform cracking extending beyond a limited area near the edge is irreparable, and the bucket/blade should be scrapped. As repair technology is ever changing and evolving, what once was a limit may now be excessively conservative. To reduce scrap frequency and increase component repair yields, newer weld filler materials and alternative welding processes were tested and evaluated. Metallurgical evaluation of various types of weld filler metals as applied to the platforms of F-Class, first stage buckets cast from DS GTD111 material were undertaken. The buckets were equally processed up to but excluding weld filler and weld process type. The bucket platform welds were then simultaneously evaluated via optical microscopy. Crack free weld repairs, conducted on engine run platforms, given the appropriate heat treatments, pre- and post-welding, can be achieved with solid solutioned strengthened Inconel 625 filler, and low volume fraction gamma prime strengthened Nimonic 263 filler using conventional GTAW. Crack free weldments or minor cracking (cracks of a small number and length) can also be achieved using Laser Cladding and/or elevated temperature GTAW with IN-738 filler metal. Surprisingly the newer weld filler metal Haynes 282 and older/traditional Haynes 230, showed evidence of hot-cracking and/or micro-fissuring (strain age cracking. A large number and length of cracks was observed when using Waspaloy as the weld filler metal. Tensile and stress rupture testing of various types of welds as applied to the platform areas were also undertaken to down-select the best filler metal. Samples were removed from the platform area of engine run buckets. Some samples were then used to obtain a baseline set of parameters of the base material. Other samples were used to test weldments of various filler metals and weld processes against those baseline values obtained. Testing of elevated temperature GTAW weldments and laser cladding with IN-738 filler metal as well as conventional GTAW with Haynes 282 filler metal produced satisfactory tensile strength and ductility properties. Elevated temperature welds using IN-738 filler were able to achieve between 76–79% stress rupture life of the base metal, while laser cladding using the same filler only yielded a 60–64% value of the base material stress rupture life. The GTAW Haynes 282 samples yielded approximately between 57–64% of the base material stress rupture life. Based on the test results, the recommended procedure for GTD111DS blade platform weld repair is to use IN-738 weld filler with the elevated temperature GTAW process.
APA, Harvard, Vancouver, ISO, and other styles
4

Avramov, M. Z., I. Ivanov, V. Pavlov, and K. Zaharieva. "A robotized six degree of freedom stage for optical microscopy." In SPIE Optical Metrology 2013, edited by Fabio Remondino, Mark R. Shortis, Jürgen Beyerer, and Fernando Puente León. SPIE, 2013. http://dx.doi.org/10.1117/12.2021461.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Cheruvu, N. S., K. S. Chan, and D. W. Gandy. "Effect of Time and Temperature on TBC Failure Mode Under Oxidizing Environment." In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-51528.

Full text
Abstract:
Thermal barrier coatings (TBC) have been recently introduced on hot section components; such as transition pieces and first two stages of turbine blades and vanes of advanced F, G, and H class land-based turbine engines. The TBC coating is typically applied on metallic coated components. The metallic bond coat provides oxidation and/or corrosion protection. It is generally believed that the primary failure mode of TBCs is delamination and fracture of the top ceramic coating parallel to the bond coat in the proximity of the thermally grown oxide (TGO) between the coatings. One of the concerns associated with the use of a TBC as a prime reliant coating is its long-term stability. The effect of long-term operation at typical land based turbine operating temperatures below 1010°C (1850°F) on the failure mode of TBCs is unknown. Long-term isothermal tests were conducted on the TBC coated specimens at three temperatures, 1010°C (1850°F), 1038°C (1900°F), and 1066°C (1950°F) to determine the effects of long term exposure on the TBC failure location (mode). Following isothermal testing, the samples were destructively examined to characterize the degradation of TBC and determine the extent of TGO cracking, TGO growth, bond coat oxidation, and TBC failure location after long term exposure for up to 18000 hours. Optical microscopy and scanning electron microscope (SEM) attached with an energy dispersive spectroscopy (EDS) system were used to study the degradation of the TBC and bond coatings. The results showed that long term isothermal exposure leads to a change in the TBC failure mode from delamination of TBC at the TGO/TBC interface to internal oxidation of the bond coat and the bond coat delamination. In this paper, the effect of long-term exposure on delamination of TBC and bond coat failure mode is discussed.
APA, Harvard, Vancouver, ISO, and other styles
6

Zhou, Yongkai, Shik Lin Lee, Chao Fu, Younan Hua, and Xiaomin Li. "Fault Isolation and TEM Study in State-of-Art Thin-Film Transistors." In ISTFA 2015. ASM International, 2015. http://dx.doi.org/10.31399/asm.cp.istfa2015p0374.

Full text
Abstract:
Abstract In this work, we discussed the fault isolation method for the Thin-Film Transistor (TFT). Many defects in the TFT can be directly observed by optical microscope; however, some defects are not visible in either optical microscope or SEM making the fault isolation effort very challenging. We demonstrated that OBIRCH can be used to find defect locations in TFT failures for leakage and shorts. The TFT is so fragile that the laser power and biasing voltage have to be very carefully controlled to avoid damaging the TFT. After identifying the defect location by OBIRCH hot spot detection, the defect was successfully captured with TEM analysis.
APA, Harvard, Vancouver, ISO, and other styles
7

Akhtar, Syed Sohail, and Abul Fazal M. Arif. "Experimental and Numerical Investigation of Extrusion Die Profiles for Uniform and Effective Case-Hardening Treatment." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-87401.

Full text
Abstract:
One of the utmost challenges of hot aluminum extrusion is to design the die cavities, used to extrude thin-walled profiles, by considering the effective nitriding surface treatment of the die bearing surface in terms of nitride layer uniformity. In the present study, various AISI H13 steel samples (having commonly-used profile geometric features) are manufactured using wire EDM and subsequently nitrided using two-stage controlled nitriding treatment. The uniformity and depth of nitride layers formation on these are investigated in terms of compound layer and total nitride case depth using optical and scanning electron microscopes. Finite element code ABAQUS is used to simulate the nitrding process using sequentially coupled thermo-diffusive analysis in line with experimental set up. Both experimental and numerical results are found in close agreement in terms of nitrogen concentration and corresponding micro-hardness profiles. Some design modifications are implemented in FE code for critical die profile features for uniform nitride layer development. In view of the current results, some design guidelines are suggested for effective and uniform nitride layer formation in order to secure high quality extruded product and extended die life.
APA, Harvard, Vancouver, ISO, and other styles
8

Hu, Bihe, and Jonathon Q. Brown. "Optimization of Optical Sectioning Performance in Thick Tissue Imaging with Stage-Scanning Inverted Selective Plane Illumination Microscopy (iSPIM)." In Novel Techniques in Microscopy. Washington, D.C.: OSA, 2017. http://dx.doi.org/10.1364/ntm.2017.ntu1c.3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Zhang, Di, Ilker Capoglu, Lusik Cherkezyan, Hariharan Subramanian, Allen Taflove, and Vadim Backman. "Advances in Computational Microscopy are Facilitating Accurate Screening Techniques for Multiple Early-Stage Human Cancers." In Computational Optical Sensing and Imaging. Washington, D.C.: OSA, 2015. http://dx.doi.org/10.1364/cosi.2015.cm2e.2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Refaa, Zakariaa, Mhamed Boutaous, Shihe Xin, and Patrick Bourgin. "Towards the Enhancement of the Crystallization Kinetics of a Bio-Sourced and Biodegradable Polymer PLA (Poly (Lactic Acid))." In ASME 2014 4th Joint US-European Fluids Engineering Division Summer Meeting collocated with the ASME 2014 12th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/fedsm2014-21952.

Full text
Abstract:
PLA (Poly Lactic Acid) is a bio-sourced and a biodegradable polymer. It represents an interesting substitute for some petrochemical based polymers, especially because of its wide range of applications in the biomedical, agriculture and packaging fields. Unfortunately, PLA exhibits slow crystallization kinetics, limiting the amount of crystallinity in the final product, which is a handicap in order to extend its use. Many authors have investigated the crystallization of polymers; nevertheless several physical mechanisms remain not yet understood. This work aims a complete characterization of PLA in order to improve the understanding of its crystallization kinetics. The quiescent crystallization was investigated using Differential Scanning Calorimetry (DSC) measurements in isothermal and non-isothermal conditions for PLA and PLA with 5wt % talc. The flow effect on crystallization was studied using a thermocontrolled hot-stage shearing device (Linkam) coupled with an optical microscope. The number of activated nuclei and the growth rate were measured as functions of temperature. In addition, the linear viscoelastic properties were obtained from a rheometer with plate-plate geometry. The enhancement of the crystallization was quantified and analyzed in terms of the half crystallization time t1/2. This characteristic time t1/2 is found to be drastically decreased by both the talc and the flow which promote supplementary nucleation leading to various crystalline microstructures. The flow is known to orient and stretch molecules leading to an extra nucleation. An original description of this phenomenon is proposed using two characteristic Weissenberg numbers; based on the definition of Rousse and reptation times. Finally, we have proposed a semi-empirical model to quantify the thermal and flow contributions on the crystallization.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Hot Stage Optical Microscopy' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography