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Accurate sample heating is vital for nucleic acid extraction and amplification, requiring a sophisticated thermal cycling process in nucleic acid detection. Traditional molecular detection systems with heating capability are bulky, expensive, and primarily designed for lab settings. Consequently, their use is limited where lab systems are unavailable. This study introduces a technique for performing the heating process required in molecular diagnostics applicable for point-of-care testing (POCT), by presenting a method for crafting customized heaters using freely patterned nichrome (NiCr) wire. This technique, fabricating heaters by arranging protrusions on a carbon black-polydimethylsiloxane (PDMS) cast and patterning NiCr wire, utilizes cost-effective materials and is not constrained by shape, thereby enabling customized fabrication in both two-dimensional (2D) and three-dimensional (3D). To illustrate its versatility and practicality, a 2D heater with three temperature zones was developed for a portable device capable of automatic thermocycling for polymerase chain reaction (PCR) to detect Escherichia coli (E. coli) O157:H7 pathogen DNA. Furthermore, the detection of the same pathogen was demonstrated using a customized 3D heater surrounding a microtube for loop-mediated isothermal amplification (LAMP). Successful DNA amplification using the proposed heater suggests that the heating technique introduced in this study can be effectively applied to POCT.
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Lee, Jung-Yeop, Hong-Chul Park, Jung-Yeul Jung, and Ho-Young Kwak. "Bubble Nucleation on Micro Line Heaters." Journal of Heat Transfer 125, no. 4 (July 17, 2003): 687–92. http://dx.doi.org/10.1115/1.1571844.
Nucleation temperatures on micro line heaters were measured precisely by obtaining the I-R (current-resistance) characteristic curves of the heaters. The bubble nucleation temperature on the heater with 3 μm width is higher than the superheat limit, while the temperature on the heater with broader width of 5 μm is considerably less than the superheat limit. The nucleation temperatures were also estimated by using the molecular cluster model for bubble nucleation on the cavity free surface with effect of contact angle. The bubble nucleation process was observed by microscope/35 mm camera unit with a flash light of μs duration.
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Povolotskiy, Alexey V., Oksana S. Smirnova, Diana A. Soldatova, Anastasia V. Povolotckaia, and Daniil A. Lukyanov. "High-Precision Optical Excited Heaters Based on Au Nanoparticles and Water-Soluble Porphyrin." Metals 13, no. 11 (November 5, 2023): 1851. http://dx.doi.org/10.3390/met13111851.
Gold nanoparticles are widely used as local heaters under optical excitation. Hybrid molecular-plasmon nanostructures based on gold nanoparticles and water-soluble porphyrin have been developed. A colloidal solution of gold nanoparticles was obtained by laser ablation of metallic gold in water, ensuring its highest chemical purity. The hybrid nanostructures formation was performed due to the Coulomb interaction of cationic porphyrin and gold nanoparticles. The revealed functional properties of hybrid nanostructures make them promising for controllable nano-heater applications (for example, photothermal therapy). Gold nanoparticles act as heaters, whereas porphyrin serves as a fluorescent thermometer with a single optical excitation.
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Park, Jaesoung, Suhan Lee, Dong-Ik Kim, Young-You Kim, Samsoo Kim, Han-Jung Kim, and Yoonkap Kim. "Evaporation-Rate Control of Water Droplets on Flexible Transparent Heater for Sensor Application." Sensors 19, no. 22 (November 12, 2019): 4918. http://dx.doi.org/10.3390/s19224918.
To develop high-performance de- or anti-frosting/icing devices based on transparent heaters, it is necessary to study the evaporation-rate control of droplets on heater surfaces. However, almost no research has been done on the evaporation-rate control of liquid droplets on transparent heaters. In this study, we investigate the evaporation characteristics of water droplets on transparent heater surfaces and determine that they depend upon the surface wettability, by modifying which, the complete evaporation time can be controlled. In addition, we study the defrosting and deicing performances through the surface wettability, by placing the flexible transparent heater on a webcam. The obtained results can be used as fundamental data for the transparent defrosting and deicing systems of closed-circuit television (CCTV) camera lenses, smart windows, vehicle backup cameras, aircraft windows, and sensor applications.
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Park, Jeonhyeong, Il Ryu Jang, Kyungtaek Lee, and Hoe Joon Kim. "High Efficiency Crumpled Carbon Nanotube Heaters for Low Drift Hydrogen Sensing." Sensors 19, no. 18 (September 9, 2019): 3878. http://dx.doi.org/10.3390/s19183878.
This work presents the fabrication of crumpled carbon nanotubes (C-CNTs) thin film heaters and their application towards high sensitivity and low drift hydrogen gas sensing. Utilizing a spray coating of pristine multi-walled carbon nanotubes (MWCNTs) and thermal shrinkage of polystyrene (PS) substrate, we have fabricated C-CNTs with closely packed junctions. Joule heating of C-CNTs gives higher temperature at a given input voltage compared to as-deposited CNTs. In addition, temperature coefficient of resistance (TCR) is analyzed for accurate temperature control and measurement of the heater. The C-CNT heaters are capable of hydrogen gas sensing while demonstrating higher measurement sensitivities along with lower drift compared to as-deposited CNT devices. In addition, the self-heating of C-CNT heaters help rapid desorption of hydrogen, and thus allowing repetitive and stable sensor operation. Our findings reveal that both CNT morphologies and heating temperatures affect the hydrogen sensing performances.
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Lin, Xi, Rong Huang, and Mathias Ulbricht. "Novel magneto-responsive membrane for remote control switchable molecular sieving." Journal of Materials Chemistry B 4, no. 5 (2016): 867–79. http://dx.doi.org/10.1039/c5tb02368h.
Magneto-responsive separation membrane: reversible change of molecule sieving through pore-confined polymeric hydrogel network by remote control of immobilized “nano heaters” with alternating magnetic field.
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Elkassabgi, Y., and J. H. Lienhard. "Influences of Subcooling on Burnout of Horizontal Cylindrical Heaters." Journal of Heat Transfer 110, no. 2 (May 1, 1988): 479–86. http://dx.doi.org/10.1115/1.3250511.
The peak pool boiling heat flux is observed on horizontal cylindrical heaters in acetone, Freon-113, methanol, and isopropanol over ranges of subcooling from zero to 130° C. Photographs, and the data themselves, revealed that there are three distinct burnout mechanisms at different levels of subcooling. Three interpretive models provide the basis for accurate correlations of the present data, and data from the literature, in each of the three regimes. Burnout is dictated by condensation on the walls of the vapor jets and columns at low subcooling. In the intermediate regime, burnout is limited by natural convection, which becomes very effective as vapor near the heater reduces boundary layer resistance. Burnout in the highsubcooling regime is independent of the layer of subcooling, and is limited by the process of molecular effusion.
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Qureshi, Shafiq R., Waqar A. Khan, and Waqas Sarwar. "EPDM Based Double Slope Triangular Enclosure Solar Collector: A Novel Approach." Scientific World Journal 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/576101.
Solar heating is one of the important utilities of solar energy both in domestic and industrial sectors. Evacuated tube heaters are a commonly used technology for domestic water heating. However, increasing cost of copper and nickel has resulted in huge initial cost for these types of heaters. Utilizing solar energy more economically for domestic use requires new concept which has low initial and operating costs together with ease of maintainability. As domestic heating requires only nominal heating temperature to the range of 60–90°C, therefore replacing nickel coated copper pipes with any cheap alternate can drastically reduce the cost of solar heater. We have proposed a new concept which utilizes double slope triangular chamber with EPDM based synthetic rubber pipes. This has reduced the initial and operating costs substantially. A detailed analytical study was carried out to design a novel solar heater. On the basis of analytical design, a prototype was manufactured. Results obtained from the experiments were found to be in good agreement with the analytical study. A maximum error of 10% was recorded at noon. However, results show that error is less than 5% in early and late hours.
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M L, Bharathi, T. Sripriya, B. Muthuraj, D. Sateesh Kumar, V. Venkatesh, Badireddy Satya Sridevi, Munaga Masthan Siva Krishna, K. Rajan, and Abdi Diriba. "Deep Learning-Based Smart Hybrid Solar Water Heater Erection Model to Extract Maximum Energy." International Journal of Photoenergy 2022 (October 3, 2022): 1–8. http://dx.doi.org/10.1155/2022/2943386.
Currently, we are trying to get electricity in alternative ways. Many solar powered water heaters have come up to use water heaters. However, these tools are not 100 percent fully effective. The device we have manufactured is an automatic device that runs in the direction of sunlight. The device runs automatically in the morning facing east and in the evening facing west. In this instrument, the defective one-inch tube lamp and the three-quarter-inch tube lamp are put together and connected in series. In this paper, a smart deep learning model was proposed to improve the performance of the solar water heater. The gap between the tube lights is filled with methane gas, and the tube inside is filled with water. The water thus filled is heated by sunlight. Methane gas acts as a fast conductor of solar heat. An electronic control device is placed to determine the temperature of the hot water and to expel the hot water. This device can heat at least 10 liters of water in 15 minutes. Increasing the number of incandescent tube lights can heat up a large amount of water when this device is set up, or it can be designed by replacing tube lights with a series of large glass tubes using the same technology. This tool can be manufactured at low cost so that people from all walks of life can use it.
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YU, HUI-MIN, and CHAO-HENG CHIEN. "MINIATURIZED PCR-CHIP FOR DNA AMPLIFICATION WITH AN EXTERNAL PERISTALTIC PUMP." Journal of Mechanics in Medicine and Biology 05, no. 01 (March 2005): 81–87. http://dx.doi.org/10.1142/s0219519405001394.
Since 1985, the polymerse chain reaction (PCR) became very popular among the field of molecular biology. It is very powerful for amplification DNA segment and it had a variety of applications in medicinal, virus, disease, and monitoring. In this study, a simple and miniature PCR chip will be presented with an external peristaltic pump utilized to driving liquid into PCR chip.1 The PCR chip was made of PMMA (Polymethylmethacrylate) and glass. The hot embossing technique was used to fabricate the micro channel on the PMMA. The copper was sputtered on the glass as the heater. The glass and PMMA were bonded by PDMS. In typically, heater temperature was 94°C for denature, 55°C for annealing, 72°C for extension. Therefore, the heaters formed three different zones of temperature along the channel that the length ration on each temperature zone was 1:1:2 for denature, annealing and extension, respectively.2,3 For temperature control, the PID control mode was used to regulate the temperature on reaction and the DC power was as the power supplier. The thermal sensors were adhered on the heater beside the channel.
Dissertations / Theses on the topic "Molecular heaters":
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Telles, Do Casal Mariana. "Molecular dynamics and electronic structure simulations of photoexcited chromophores in the gas-phase and complex environments." Electronic Thesis or Diss., Aix-Marseille, 2022. http://theses.univ-amu.fr.lama.univ-amu.fr/220916_TELLESDOCASAL_482lt726dkah904g486xpmri_TH.pdf.
Le développement d'une nouvelle classe de molécules calorifères, déposées directement sur les plantes, est une nouvelle stratégie pour étendre les lieux propices à l'agriculture à des altitudes plus élevées, en prévenant les dommages causés par le froid. L'idée sous-jacente est que ces molécules calorifères sont capables d'absorber le rayonnement UV-visible et de le convertir en chaleur, dans ce cas, à destination de la surface des feuilles. Inspirés par les stratégies photoprotectrices efficaces trouvées dans la nature, nous étudions des dérivés du malate de sinapoyle (SM). Après absorption de la lumière, ces dérivés présentent une désexcitation non radiative rapide et efficace. D'autre part, les dicétopyrrolopyrroles sont également des candidats. Le dimère possède un état doublement excité de faible énergie qui n'est pas accessible au monomère, permettant à la conversion interne de se produire en premier. Nous caractérisons la fonction d'onde de l'état doublement excité en modifiant de façon systématique les dérivés de façon à ajuster la taille du système π et les caractères de l'accepteur et du donneur. Cette analyse ouvre de nouvelles voies pour contrôler l'équilibre entre la luminescence et la conversion interne dans de tels systèmes. Cependant, une caractérisation correcte des états doublement excités reste un défi : il n'existe aucun schéma de classification rigoureux et transférable entre les méthodes. Nous proposons donc de classer les états doublement excités selon deux cas limites : les états doublement excités à couche ouverte ou fermée. Notre schéma de classification est basé sur des descripteurs extraits des matrices de la densité Developing a new class of molecular heaters to be applied in plants is a new strategy to extend locations suitable for agriculture to higher altitudes, preventing damages caused by the cold. The underlining idea is that molecular heaters can absorb UV-vis radiation and convert it into heat, in this case, to the leaves' surface. Inspired by nature and its efficient photoprotective features, we study the photophysics of derivatives of sinapoyl malate (SM). These derivatives exhibit a fast and efficient nonradiative decay through a twisted charge-transfer state. Another class of potential candidates as molecular heaters are the diketopyrrolopyrroles. The dimer has a low-lying doubly excited state that is not energetically accessible to the monomer, and this delays the fluorescence allowing internal conversion to occur first. We characterize the doubly excited state wavefunction by systematically changing the derivatives to tune the pi-scaffold size and the acceptor and donor characters. This analysis opens new ways to control the balance between luminescence and internal conversion in such systems. However, a proper characterization of doubly excited states is still a challenge, and no rigorous and transferable classification scheme between methods exists. Then, we propose classifying doubly excited states according to two limiting cases: the open- and closed-shell doubly excited states, based on descriptors extracted from density matrices
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Jones, Clive. "Heats of transport in defective solids." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364004.
Duval, B. P. "Spectroscopic studies of highly ionised atoms : A study of transitions from impurity ions in a neutral beam heated tokamak." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375254.
Darga, Alexander. "Sorption isotherms of volatile molecules on micro- and mesoporous nanosized siliceous materials based on acoustic wave devices : Determination of corresponding isosteric heats of adsorption." kostenfrei, 2008. http://edoc.ub.uni-muenchen.de/9093/.
Darga, Alexander [Verfasser]. "Sorption isotherms of volatile molecules on micro- and mesoporous nanosized siliceous materials based on acoustic wave devices : determination of corresponding isosteric heats of adsorption / von Alex Darga." 2008. http://d-nb.info/990824098/34.
This chapter deals with writings in which Boltzmann expressed the statistical nature of the entropy law and temporarily made the relation between entropy and combinatorial probability a basic constructive tool of his theory. In 1881, he discovered that this relation derived from what we now call the microcanonical distribution, and he approved Maxwell’s recent foundation of the equilibrium problem on the microcanonical ensemble. Boltzmann also kept working on problems he had tackled in earlier years. He proposed a new solution to the problem of specific heats, and he performed enormous calculations for the viscosity and diffusion coefficients in the hard-ball model. In a lighter genre, he conceived a new way of determining molecular sizes, and he speculated on a gas model in which the molecular forces would be entirely attractive.
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Darrigol, Olivier. The Critical Turn (1895–1899). Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198816171.003.0008.
In the writings of this period, we see Boltzmann responding to criticism by British kinetic theorists and by the German mathematician Ernst Zermelo regarding the equipartition of energy and the H theorem. Boltzmann also acted as a critic of other authors. He ridiculed Joseph Bertrand’s attack on Maxwell’s kinetic-molecular reasoning and, after much pounding on Max Planck’s early radiation theory, he managed to convince Planck to alter his approach to irreversibility. Boltzmann also gave a last critical review of the problem of specific heats. During the same period, he was working on his Gastheorie and this prompted him to discuss Johannes Diderik van der Waals’s theory in the light of the Maxwell–Boltzmann theory, with similar reasoning adapted to the problem of chemical dissociation.
Book chapters on the topic "Molecular heaters":
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Furka, Árpád. "Components of the Heats of Reactions." In SpringerBriefs in Molecular Science, 105–24. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-06004-6_9.
Varghese, Philip L., and David A. Gonzales. "Non-Equilibrium Chemistry Models for Shock-Heated Gases." In Molecular Physics and Hypersonic Flows, 105–14. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-0267-1_6.
Arista, N. R., and A. Gras-Martí. "Stopping Power of Large Molecular Clusters in Cold and Heated Solids." In Interaction of Charged Particles with Solids and Surfaces, 557–62. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4684-8026-9_28.
Vuong, T., and P. A. Monson. "Heats of Adsorption from Molecular Models of Adsorption in Heterogeneous Solids." In The Kluwer International Series in Engineering and Computer Science, 1009–18. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4613-1375-5_126.
Allinger, N. L. "Heats of Formation by Density Functional Theory Calculations." In Energetics of Stable Molecules and Reactive Intermediates, 417–30. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4671-5_18.
D’souza, A. J., and P. K. Brahmbhatt. "Experimental Investigation on Use of Activated Alumina and Molecular Sieve 13× In Heatless Desiccant Air Dryer." In Lecture Notes in Mechanical Engineering, 93–103. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-3379-0_9.
Chesneau, A., and R. Campargue. "Molecular Beam Time-of-Flight Measurements and Moment Method Calculations of Translational Relaxation in Highly Heated Free Jets of Monatomic Gas Mixtures." In Rarefied Gas Dynamics, 879–86. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2467-6_20.
Kulikov, S. V. "Simulation of forming a shock wave in the shock tube on the molecular level and behavior of the end of a shock-heated gas." In Shock Waves, 1503–8. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-85181-3_115.
McCash, Elaine M. "Adsorption and desorption." In Surface Chemistry. Oxford University Press, 2001. http://dx.doi.org/10.1093/hesc/9780198503286.003.0003.
This chapter examines adsorption and desorption. There are several possible outcomes when an atom or a molecule hits a surface, including elastic and inelastic scattering. However, the outcome of an atomic or a molecular collision that results in the retention of the molecule on the surface is of far greater importance to the study of surface chemistry. There are two types of interactions that can occur: physical adsorption (or physisorption) and chemisorption. In each case, the atom or molecule being adsorbed on the surface is usually described as the adsorbate; the adsorbing surface is usually termed the adsorbent or substrate. The chapter then looks at adsorption isotherms, before considering the measurement of heats of adsorption, isosteres, and desorption rates. It also discusses adsorption sites and geometries. Finally, the chapter highlights two methods which can provide information on surface chemical composition: auger electron spectroscopy (AES) and secondary ion mass spectrometry (SIMS).
Conference papers on the topic "Molecular heaters":
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Romanov, I., Mario Barbatti, Mariana Telles do Casal, Josene Toldo, Wybren Buma, and Y. Boeije. "HIGH-RESOLUTION LASER SPECTROSCOPIC STUDIES OF CINNAMATE-BASED MOLECULAR HEATERS." In 2022 International Symposium on Molecular Spectroscopy. Urbana, Illinois: University of Illinois at Urbana-Champaign, 2022. http://dx.doi.org/10.15278/isms.2022.rh03.
Lee, Jung-Yeop, Hong-Chul Park, Ho-Young Kwak, and Jin-Seok Jeon. "Bubble Nucleation on Micro Line Heaters." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/htd-24215.
Abstract Nucleation temperatures on the micro line heaters were measured precisely by obtaining the I-R (current-resistance) characteristic curves of the heaters. The bubble nucleation temperatures on the heater with 3 μm width are higher than the superheat limit, while the temperature on the heater with broader width of 5 μm are considerably less than the superheat limit. The nucleation temperatures were also estimated by using the molecular cluster model of bubble nucleation with effect of contact angle. The bubble nucleation process was observed by microscope / 35 mm camera unit with a flash light of μs duration.
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Ting-Ting Wu, Jing-Quan Liu, Shui-Dong Jiang, Bin Xu, Bin Yang, Hong-Ying Zhu, and Chun-Sheng Yang. "Electrical properties of micro-heaters using sputtered NiCr thin film." In 2013 8th IEEE International Conference on Nano/Micro Engineered and Molecular Systems (NEMS). IEEE, 2013. http://dx.doi.org/10.1109/nems.2013.6559771.
Zhu, Taishan, and Wenjing Ye. "Gas-Phase Heat Transfer From a Heated Microcantilever Inside a Vacuum Enclosure." In ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASMEDC, 2009. http://dx.doi.org/10.1115/mnhmt2009-18469.
The modeling of heat transfer inside a vacuum packaged MEMS devices has been performed by several researchers mostly through Monte Carlo simulations. In this work, we employ an analytical approach to study the heat transport of gas inside a high vacuum enclosure. In this pressure range, the interaction between gas molecules is negligible compared to their interaction with the walls, and hence the gas is treated as the free-molecule gas. The heated cantilever is modeled as a uniform beam with a rectangular cross section located at a certain distance away from the bottom wall which could represent a substrate in the real device. To account for various situations, the temperatures of the surrounding walls are allowed to be different from each other and different from that of the beam and the substrate. The temperature contour and the heat flux are obtained from the analytical approach. A molecular simulation code based on the direct simulation Monte Carlo (DSMC) has been developed and employed to validate the analytical results and excellent agreements have been obtained. The effects of incomplete thermal accommodation are also investigated. It is anticipated that the developed analytical solutions would be very valuable to the design of Pirani sensors and other MEMS devices utilizing micro heaters, for example, the thermal sensing atomic force microscope.
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Singh, Navdeep, and Debjyoti Banerjee. "Investigation of Interfacial Thermal Resistance on Nano-Structures Using Molecular Dynamics Simulations." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22930.
Due to their very high thermal conductivity carbon nanotubes have been found to be an excellent material for thermal management. Experiments have shown that the heaters coated with carbon nanotubes increase the heat transfer by as much as 60%. Also when nanotubes are used as filler materials in composites, they tend to increase the thermal conductivity of the composites. But the increase in the heat transfer and the thermal conductivity has been found to be much less than the calculated values. This decrease has been attributed to the interfacial thermal resistance between the carbon nanotubes and the surrounding material. MD simulations were performed to study the interfacial thermal resistance between the carbon nanotubes and the liquid molecules. In the simulations, the nanotube is placed at the center of the simulation box and a temperature of 300K is imposed on the system. Then the temperature of the nanotube is raised instantaneously and the system is allowed to relax. From the temperature decay, the interfacial thermal resistance between the carbon nanotube and the liquid molecules is calculated. In this study the liquid molecules under investigation are n-heptane, n-tridecane and n-nonadecane.
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Willett, Fred T., and Arthur E. Bergles. "Heat Transfer in Rotating Narrow Rectangular Ducts With Heated Sides Oriented at 60° to the r-z Plane." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0224.
Gas turbine blade life is often limited by the effectiveness of the cooling in the trailing edge convective cavity, which generally has a narrow cross-section. Previous research on rotational effects considered cavity shapes quite different from those of typical trailing edge cavities. In this research, experiments were conducted to determine the effect of rotation on heat transfer in ducts of narrow cross-section (height-to-width ratio of 1:10), oriented with the heated sides at 60° to the r-z plane. In the experiment, a high-molecular-weight gas (Refrigerant-134A) at ambient pressure and temperature conditions was used to match the dimensionless parameters at engine conditions. Thin foil heaters were used to produce a constant heat flux at the long sides of the duct; the narrow sides were unheated. Duct Reynolds numbers were varied up to 20,000; rotation numbers were varied up to 0.25. The test results show the effect of rotation and aspect ratio on duct leading and trailing side heat transfer. In addition, the results show the variation in heat transfer coefficient with transverse location in the duct, demonstrating the effect of rotation not only on lead and trail side heat transfer, but also on forward and aft end heat transfer.
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Vieira, Anderson Jalles de Meneses, Cassiano Gomes Aimoli, and Dárley Carrijo de Melo. "Comparison Between Molecular Sieves and Activated Alumina for Gas Dehydration in an Ultra-Deepwater Production Unit." In Offshore Technology Conference. OTC, 2023. http://dx.doi.org/10.4043/32580-ms.
Abstract Activated alumina and molecular sieve performances are compared regarding key parameters such as adsorbed water load, outlet moisture content, pressure drop and adsorption capacity using different regeneration conditions. The comparison was done by operating one out of three vessels of a Brazilian pre-salt FPSO gas dehydration unit loaded with activated alumina, whereas the other two vessels were loaded with molecular sieves with a silica gel top layer. During the early operation of the alumina, tests were performed by increasing adsorption time until the moisture breakthrough, conducted in two operational setups as follows: 1) a parallel-flow arrangement in which each vessel is loaded with one of the adsorbent materials, named dual bed phase; 2) a single stream flow to the vessel containing activated alumina, named single bed phase. Different regeneration temperatures were tested to verify the impact on the alumina capacity caused by low temperature regeneration. The results were compared to historical data collected using both type 4A and chabazite zeolites. During preliminary capacity tests performed in laboratory and in pilot scale, the activated alumina delivered gas with moisture content generally between 1 and 10 ppm. However, during the industrial scale test reported here, the activated alumina was able to consistently deliver gas with moisture under 1 ppm after its first regeneration, operating both in single bed and dual bed arrangement. This result indicates that activated alumina was able to achieve gas specification once considered possible only by the use of molecular sieve. The initial dynamic capacity calculated for the alumina was comparable to the maximum dynamic capacities observed for the molecular sieves. In this test, the larger particle size of the activated alumina compared to the zeolites resulted in lower pressure drop through the alumina bed, culminating into an uneven flow distribution between both beds when in parallel-flow arrangement. Recommended regeneration temperatures are lower for alumina in comparison with the zeolites, resulting in lower energy consumption and associated CO2 emissions when using electrical heaters. The novelty of this work lies in the use of activated alumina as the main adsorbent material in an ultra-deepwater gas dehydration unit with gas processing capacity over 6 MMSCMD achieving dry gas moisture as low as obtained by using molecular sieves. The use of activated alumina shows potential to improve efficiency and cost reduction that has yet to be confirmed by a longer test phase to check its stability and long-term performance.
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Amano, Ryo S., Jose Martinez Lucci, Krishna S. Guntur, M. Mahmun Hossain, M. Monzur Morshed, Matthew E. Dudley, and Franklin Laib. "Experimental Study of Treating Volatile Organic Compounds." In ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-34579.
Heated Soil Vapor Extraction (HSVE) is a technology that has been used successfully to clean up subsurface soils at sites containing chlorinated solvents and petroleum hydrocarbons. The costs have been extremely high due to the large amount of energy required to volatilize high molecular weight polycyclic aromatic hydrocarbon (PAH) compounds present in the soil matrix. One remediation contractor states that hydrocarbons are oxidized in situ by achieving temperatures in the >1000 F range near the heaters [1]. A critical question is whether the volatile portion of manufactured gas plant (MGP) hydrocarbons (VOCs) can be stripped out at lower temperatures such that the remaining contaminants will be unavailable for transport or subsequent dissolution into the groundwater. Soil remediation by heated soil vapor extraction system is a relatively new technology developed by Jay Jatkar Inc. (JJI) along with the University of Wisconsin-Milwaukee [2]. The areas around chemical companies or waste disposal sites have been seriously contaminated from the chemicals and other polluting materials that are disposed off. The process developed by JJI, consists of a heater/boiler that pump and circulates hot oil through a pipeline that is enclosed in a larger-diameter pipe. This extraction pipe is vertically installed within the contaminated soil up to a certain depth and is welded at the bottom and capped at the top. The number of heat source pipes and the extraction wells depends on the type of soil, the type of pollutants, moisture content of the soil and the size of the area to be cleaned. The heat source heats the soil, which is transported in the interior part of the soil by means of conduction and convection. This heating of soil results in vaporization of the gases, which are then driven out of the soil by the extraction well. The extraction well consists of the blower which would suck the vaporized gases out of the system. Our previous studies had removed higher boiling compounds, such as naphthalene, etc., to a non-detectable level. Thus, the current technology is very promising for removing most of the chemical compounds; and can also remove these boiling compounds from the saturated zone. Gas chromatography (GC) is utilized in monitoring the relative concentration changes over the extraction period. Gas chromatography-mass spectrometry (GC-MS) assists in the identification and separation of extracted components. The experimental research is currently being conducted at the University of Wisconsin-Milwaukee. The objectives of this study are to identify contaminants and time required to remove them through HSVE treatment and provide data for computation fluid dynamics CFD analysis.
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Amano, Ryo S., Jose Martinez Lucci, and Krishna S. Guntur. "Experimental and Computational Study of Vaporization of Volatile Organic Compounds." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41086.
Heated Soil Vapor Extraction (HSVE) is a technology that has been used successfully to clean up subsurface soils at sites containing chlorinated solvents and petroleum hydrocarbons. The costs have been extremely high due to the large amount of energy required to volatilize high molecular weight polycyclic aromatic hydrocarbon (PAH) compounds present in the soil matrix. One remediation contractor states that hydrocarbons are oxidized in situ by achieving temperatures in the >1000 F range near the heaters [1]. A critical question is whether the volatile portion of manufactured gas plant (MGP) hydrocarbons (VOCs) can be stripped out at lower temperatures such that the remaining contaminants will be unavailable for transport or subsequent dissolution into the groundwater. Soil remediation by heated soil vapor extraction system is a relatively new technology developed at the University of Wisconsin-Milwaukee [2]. The areas around chemical companies or waste disposal sites have been seriously contaminated from the chemicals and other polluting materials that are disposed off. The process developed at UWM, consists of a heater/boiler that pump and circulates hot oil through a pipeline that is enclosed in a larger-diameter pipe. This extraction pipe is vertically installed within the contaminated soil up to a certain depth and is welded at the bottom and capped at the top. The number of heat source pipes and the extraction wells depends on the type of soil, the type of pollutants, moisture content of the soil and the size of the area to be cleaned. The heat source heats the soil, which is transported in the interior part of the soil by means of conduction and convection. This heating of soil results in vaporization of the gases, which are then driven out of the soil by the extraction well. The extraction well consists of the blower which would suck the vaporized gases out of the system. Our previous studies had removed higher boiling compounds such as naphthalene, etc., to non-detectable level. Thus, the current technology is very promising for removing most of the chemicals compounds; and can also remove these high boiling compounds from the saturated zone. Gas chromatography (GC) is utilized in monitoring the relative concentration changes over the extraction period. Gas chromatography-mass spectrometry (GCMS) assists in the identification and separation of extracted components. The experimental research is currently being conducted at the University of Wisconsin-Milwaukee. The objectives of this study are to identify contaminants and time required to remove them through HSVE treatment and provide data for computation fluid dynamics CFD analysis.
10
Borca-Tasciuc, Theodorian. "Heat Conduction Across Nanoscale Interfaces and Nanomaterials for Thermal Management and Thermoelectric Energy Conversion." In ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels collocated with 3rd Joint US-European Fluids Engineering Summer Meeting. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-31312.
Nanoscale heat conduction plays a critical role in applications ranging from thermal management of nanodevices to nanostructured thermoelectric materials for solid state refrigeration and power generation. This lecture presents recent investigations in our group. The first part of the lecture demonstrates heat conduction across nanoscale interfaces formed between individual nanoscale heaters and the silicon substrate [1]. A systematic experimental study was performed of thermal transport from individual nanoscale heaters with widths ranging between 77nm-250nm to bulk silicon substrates in the temperature range of 80–300K. The effective substrate thermal conductivity was measured by joule heating thermometry. We report up to two orders of magnitude reductions in the measured effective thermal conductivity of the silicon substrate when the heater widths are smaller than the mean free path of the heat carriers in the substrate, as summarized in Fig. 1. The effective mean free path of the silicon substrate was extracted from the measurements and was found to be comparable with recent molecular dynamics simulations. A proof of concept demonstration of a novel Thermal Interface Material (TIM) is presented next. The high thermal conductivity TIM is based on a highly connected high thermal conductivity nanostructured filler network embedded in a polymer matrix where the contribution of filler-matrix interfaces to thermal resistance is minimized. It was found [2] that the thermal conductivity could be varied from ∼0.2 to 20 W/mK when the volume fraction of metallic nanoparticles was varied from 0–20%. For similar volume fractions and filler composition, microparticle based composites have two orders of magnitude lower thermal conductivities. SEM characterization and thermal transport modeling are employed to support the conclusion that morphological changes in the nano-TIM are responsible for the thermal conductivity reduction. Thermoelectric transport investigations are discussed for a novel class of highly scalable nanostructured bulk chalcogenides developed at Rensselaer Polytechnic Institute [3]. Un-optimized, single-component bulk assemblies of Bi2Te3 and Sb2Te3 single crystal nanoplates show large enhancements (25–60%) in the room temperature thermoelectric figure of merit compared with individual bulk counterparts (Table 1). Nanostructuring was found to lead to strong thermal conductivity reduction without significantly affecting the mobility of the charge carriers, as shown in Table 2. A scanning thermal microprobe technique developed for simultaneous thermal conductivity (κ) and Seebeck coefficient (α) measurements in thermoelectric films is also presented [4]. In this technique, an AC alternative current joule-heated V-shaped microwire that serves as heater, thermometer and voltage electrode, locally heats the thin film when contacted with the surface (Fig. 2). The κ is extracted from the average DC temperature rise thermal resistance of the microprobe and α from the DC Seebeck voltage measured between the probe and unheated regions of the film by modeling the heat transfer in the probe, sample and their contact area, and by calibrations with standard reference samples. Application of the technique on sulfur-doped porous Bi2Te3 and Bi2Se3 films reveals α = −105.4 and 1.96 μV/K, respectively, which are within 2% of the values obtained by independent measurements carried out using microfabricated test structures. The respective κ values are 0.36 and 0.52 W/mK, which are significantly lower than the bulk values due to film porosity, and are consistent with effective media theory. The dominance of air conduction at the probe-sample contact area determines the microscale spatial resolution of the technique and allows probing samples with rough surfaces. Non-contact mode measurement of thermal conductivity was also demonstrated and confirmed by independent characterization [5]. In non-contact mode the technique utilizes ballistic air conduction as the dominant heat transfer mechanism between the thermal probe and the sample and thus eliminates uncertainties due to solid contact and liquid meniscus conduction.
Reports on the topic "Molecular heaters":
1
Baer, T. PEPICO (photoelectron photoion coincidence) studies of ion dissociations: The structure and heats of formation of ions, molecules, and free radicals. Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/6859581.
Baer, T. Studies of ion dissociation: Structure and heats of formation of ions, molecules, and free radicals: Progress report, August 1988--April 1989. Office of Scientific and Technical Information (OSTI), January 1989. http://dx.doi.org/10.2172/5838032.
