Journal articles: 'Vibrational energy][Cryogenics'

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Simpson, C. J. S. M., M. L. Turnidge, and J. P. Reid. "Vibrational energy transfer between molecules dissolved in cryogenic liquids." Journal of Molecular Liquids 70, no. 2-3 (November 1996): 125–31. http://dx.doi.org/10.1016/0167-7322(96)00962-2.

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Puchkin, Vladimir, Ilya Turkin, Larisa Salanti, Olga Sumskaja, and Vladimir Kornienko. "Study increase the mechanical characteristics of tool materials by cryogenic treatment." E3S Web of Conferences 279 (2021): 01011. http://dx.doi.org/10.1051/e3sconf/202127901011.

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In this work, the hypothesis of taking into account a specific thermoEMF to determine the degree of hardening of the cutting tool by cryogenic hardening is put forward, which is the most convenient and important value from the point of view of information content. As a result of studies of improving the mechanical characteristics of instrumental materials by cryogenic treatment, the values of the absolute and specific values of thermo emf were revealed depending on the temperature of three instrumental materials obtained by tarrying them together with platinum. The values of temperatures at the maximum values of the specific thermo emf, have been obtained. It was found that deep cooling of the metal increases the degree of ordering of its structure and increases the vibrational energy of the crystal lattice. The results of the study showed that the resistance of the cryogenic cutting tool increases by up to three times, this positively affects the energy efficiency of the use of such a tool in production. The reduction of energy costs is expressed in the reduction of kilowatt-hours associated with the costs of sharpening the tool and can reach up to 30% of the total amount of electricity consumed.

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Steinmann, Ricardo G., Gema Martinez-Criado, Damien Salomon, Hugo Vitoux, Remi Tucoulou, Julie Villanova, Sylvain Laboure, Joel Eymery, and Jaime Segura-Ruiz. "A helium mini-cryostat for the nanoprobe beamline ID16B at ESRF: characteristics and performance." Journal of Synchrotron Radiation 27, no. 4 (June 16, 2020): 1074–79. http://dx.doi.org/10.1107/s1600577520007110.

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A helium mini-cryostat has been developed for the hard X-ray nanoprobe ID16B of the European Synchrotron to collect X-ray excited optical luminescence and X-ray fluorescence at low temperature (<10 K). The mini-cryostat has been specifically designed to fit within the strong space restrictions and high-demanding mechanical constraints imposed by the beamline to provide vibration-free operation and maximal thermal stability. This paper reports the detailed design, architecture and technical requirements of the mini-cryostat, and presents the first experimental data measured using the cryogenic equipment. The resulting cryo-system features ultimate thermal stability, fast cool-down and ultra-low vibrations. The simultaneous X-ray fluorescence and X-ray excited optical luminescence data acquired from bulk GaN and core/shell InGaN/GaN multi-quantum wells validated the excellent performance of the cryostat with ultimate resolution, stability and sensitivity.

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Borba, A., L. I. L. Cabral, R. Fausto, and M. L. S. Cristiano. "Structure, vibrational spectroscopy, and photochemistry of 5-phenoxy-1-phenyltetrazole in argon and nitrogen cryomatrices." Canadian Journal of Chemistry 93, no. 12 (December 2015): 1335–44. http://dx.doi.org/10.1139/cjc-2015-0025.

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The molecular structure, infrared spectra, and photochemistry of 5-phenoxy-1-phenyltetrazole (5PPT) isolated in argon and N2 cryogenic matrices were investigated by infrared spectroscopy and theoretical calculations (DFT(B3LYP)/6-311++G(d,p)). Calculations yield two dissimilar minima on the potential energy surface of the molecule, both being eightfold degenerate by symmetry and belonging to the C1 symmetry point group. Extensive analysis of the potential energy landscape of the molecule was performed. Upon consideration of the zero-point vibrational correction to the energy, the calculations predict that the higher energy minimum shall relax barrierlessly to the lower energy form, leading to conclude that the compound exists in a single conformer in the gas phase. Accordingly, a single conformer was observed and fully characterized spectroscopically upon isolation of the monomer of the compound in argon and nitrogen cryomatrices. UV-laser irradiation (λ = 250 nm) of matrix-isolated 5PPT leads to photocleavage of the tetrazole ring, with release of N2 and formation of the corresponding carbodiimide.

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Toellner, T. S., J. Collins, K. Goetze, M. Y. Hu, C. Preissner, E. Trakhtenberg, and L. Yan. "Ultra-stable sub-meV monochromator for hard X-rays." Journal of Synchrotron Radiation 22, no. 5 (July 17, 2015): 1155–62. http://dx.doi.org/10.1107/s1600577515012230.

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A high-resolution silicon monochromator suitable for 21.541 keV synchrotron radiation is presented that produces a bandwidth of 0.27 meV. The operating energy corresponds to a nuclear transition in151Eu. The first-of-its-kind, fully cryogenic design achieves an energy-alignment stability of 0.017 meV r.m.s. per day, or a 100-fold improvement over other meV-monochromators, and can tolerate higher X-ray power loads than room-temperature designs of comparable resolution. This offers the potential for significantly more accurate measurements of lattice excitation energies using nuclear resonant vibrational spectroscopy if combined with accurate energy calibration using, for example, high-speed Doppler shifting. The design of the monochromator along with its performance and impact on transmitted beam properties are presented.

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UCHIYAMA, TAKASHI. "PRESENT STATUS OF CLIO IN 2004." International Journal of Modern Physics A 20, no. 29 (November 20, 2005): 7066–68. http://dx.doi.org/10.1142/s0217751x05030843.

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The CLIO project in Japan consists of two kinds of interferometric detectors in a tunnel of Kamioka mine. One is a geophysical strain meter and the other one is a gravitational wave (GW) detector. The GW detector is called Cryogenic Laser Interferometer Observatory (CLIO). The characteristics of CLIO are the use of cryogenic to reduce the thermal noises and an underground site for low seismic vibration. CLIO is under construction, and installation of the first cryogenic system was completed in the autumn of 2004.

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TOMARU, TAKAYUKI, TOSHIKAZU SUZUKI, TOMIYOSHI HARUYAMA, TAKAKAZU SHINTOMI, NOBUAKI SATO, AKIRA YAMAMOTO, YUKI IKUSHIMA, et al. "SMALL VIBRATION CRYOCOOLER SYSTEM FOR CRYOGENIC GRAVITATIONAL WAVE INTERFEROMETER." International Journal of Modern Physics A 20, no. 29 (November 20, 2005): 7063–65. http://dx.doi.org/10.1142/s0217751x05030831.

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An ultra-small vibration cryocooler system for a cryogenic interferometric gravitational wave detector has been developed. The system consists of a pulse tube cryocooler and a vibration-reduction system. Its vibration level was about 50 nm for the vertical direction at 1 Hz, which was three orders of magnitude smaller than that of an original pulse tube cryocooler.

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Oliver, V. I., and V. T. Shvetsov. "Reduction of vibrations in gas cryogenic machines." Chemical and Petroleum Engineering 24, no. 4 (April 1988): 180–83. http://dx.doi.org/10.1007/bf01837181.

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Oliver, V. I., Yu O. Prusman, A. V. Gromov, and V. V. Den'gin. "High-frequency vibrations of gas cryogenic machines." Chemical and Petroleum Engineering 25, no. 9 (September 1989): 495–97. http://dx.doi.org/10.1007/bf01156020.

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Cantargi, Florencia, Javier Dawidowski, Christian Helman, José Ignacio Márquez Damian, Rolando Jose Granada, Giovanni Romanelli, Julio Gabriel Cuello, Goran Skoro, and Matthew Krzystyniak. "Validated scattering kernels for triphenylmethane at cryogenic temperatures." EPJ Web of Conferences 239 (2020): 14002. http://dx.doi.org/10.1051/epjconf/202023914002.

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Cold neutrons are widely used in different fields of research such as the study of the structure and dynamics of solids and liquids, the investigation of magnetic materials, biological systems, polymer science, and a rapidly growing area of industrial applications. In a pulsed neutron source where the pulse width is an important parameter to be considered, hydrogenated materials are often used because of their high energy transfer in each collision. The preliminary scattering kernel for triphenylmethane, a material of great potential interest for cold neutron production, had been presented at the ND2016 conference. Here, a new model for the generation of the scattering kernels for this material, together with experimental results on its total cross section measured at the VESUVIO instrument (ISIS Neutron and Muon Source, United Kingdom) is presented. The thermal scattering kernel was generated by means of the NJOY Nuclear Data Processing system, using as input the vibrational modes obtained by density functional theory techniques (DFT). The agreement between measurements and our model validates the scattering kernel construction and the cross section library generated in ENDF and ACE formats.

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Ford, Thomas A. "The Structures, Molecular Orbital Properties and Vibrational Spectra of the Homo- and Heterodimers of Sulphur Dioxide and Ozone. An Ab Initio Study." Molecules 26, no. 3 (January 25, 2021): 626. http://dx.doi.org/10.3390/molecules26030626.

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The structures of a number of dimers of sulphur dioxide and ozone were optimized by means of a series of ab initio calculations. The dimer species were classified as either genuine energy minima or transition states of first or higher order, and the most probable structures consistent with the experimental data were confirmed. The molecular orbitals engaged in the interactions resulting in adduct formation were identified and relations between the orbitals of the dimers of the valence isoelectronic monomer species were examined. The vibrational spectra of the most probable structures were computed and compared with those reported in the literature, particularly with spectra observed in cryogenic matrices. The calculations were extended to predict the properties of a number of possible heterodimers formed between sulphur dioxide and ozone.

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Aleksandrova, I. V., A. A. Akunets, E. R. Koresheva, E. L. Koshelev, and T. P. Timasheva. "Ultrafine Hydrogen Layer Formation in a Cryogenic Target under External Vibrational Influence." Physics of Atomic Nuclei 81, no. 7 (December 2018): 1081–92. http://dx.doi.org/10.1134/s1063778818070013.

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BÜSCHER, M., A. BOUKHAROV, A. SEMENOV, A. GERASIMOV, V. CHERNETSKY, and P. FEDORETS. "PRODUCTION OF HYDROGEN, NITROGEN AND ARGON PELLETS WITH THE MOSCOW-JÜLICH PELLET TARGET." International Journal of Modern Physics E 18, no. 02 (February 2009): 505–10. http://dx.doi.org/10.1142/s0218301309012562.

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Targets of frozen droplets ("pellets") from various liquefiable gases like H 2, D 2, N 2, Ne , Ar , Kr and Xe are very promising for high luminosity experiments with a 4π detector geometry at storage-rings. High effective target densities (> 1015 atoms / cm 2), a small target size (⊘ ≈ 20–30 μ m ), a low gas load and a narrow pellet beam are the main advantages of such targets. Pioneering work on pellet targets has been made at Uppsala, Sweden.1 A next generation target has been built at the IKP of FZJ in collaboration with two institutes (ITEP and MPEI) from Moscow, Russia. It is a prototype for the future pellet target at the PANDA experiment at FAIR/HESR (supported by INTAS 06-1000012-8787, 2007/08) and makes use of a new cooling and liquefaction method, based on cryogenic liquids instead of cooling machines.2 The main advantages of this method are the vibration-free cooling and the possibility for cryogenic jet production from various gases in a wide range of temperatures. Different regimes of pellet production from H 2, N 2 and Ar have been observed and their parameters have been measured.3 For the first time, mono-disperse and satellite-free droplet production was achieved for cryogenic liquids from H 2, N 2 and Ar .

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Hancock, Gus. "Ian William Murison Smith. 15 June 1937—8 November 2016." Biographical Memoirs of Fellows of the Royal Society 64 (February 14, 2018): 401–19. http://dx.doi.org/10.1098/rsbm.2017.0033.

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Ian Smith was one of the world-wide leading researchers into reaction kinetics, energy transfer and molecular dynamics in gas phase systems. He was able to span all of these aspects of collisional behaviour, and to form connections and insights that allowed him to make advances in all of them, advances which have stood the tests of time. His graduate work at the University of Cambridge was followed by academic positions in Cambridge and in Birmingham. He provided new insights into molecular energy transfer by systematically measuring how vibrational frequencies and multipole moments influenced the magnitude of the energy transfer cross sections. In reaction kinetics his detailed work on the OH radical has led to an understanding of the importance of its reactions not only in applied areas such as atmospheric and combustion chemistry, but also in fundamental dynamical studies of radical recombination and the effect of reagent energies on reactive processes. Of particular significance has been his development of both cryogenic and nozzle expansion methods of studying collisional processes at temperatures down to 10 K, with the discovery that reactions without activation barriers can get faster as the temperature decreases. The impact of this work upon astrochemistry has been profound, and has stimulated theoretical explanations of the effect. He was one of the first pioneers in the UK of the use of laser techniques to study collisional processes, using laser-induced fluorescence as a sensitive detection tool, UV laser photolysis to form reactive species and laser pumping to create excited state populations in order to observe their effect upon reaction pathways and vibrational relaxation. Ian was devoted to his family—his wife Sue, their four children and 11 grandchildren. His research collaborators will always remember his scholarship, his unending suggestions of interesting problems to study, his deep integrity and humanity. His legacy lives on with his personal and academic families.

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Ghosh, Subrata, Parboti Mukherjee, and Sunil Sarangi. "Development of bearings for a small high speed cryogenic turboexpander." Industrial Lubrication and Tribology 64, no. 1 (February 3, 2012): 3–10. http://dx.doi.org/10.1108/00368791211196835.

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PurposeThe purpose of this paper is to examine the development of aerodynamic thrust bearings and aerodynamic journal bearings applied to a small high speed cryogenic turboexpander in Indian conditions.Design/methodology/approachAs a part of indigenous programme in the process of development, some input parameter was taken from the available literature and then dimensions were optimized and computed while taking care to minimize fabrication constraints.FindingsA series of tests were conducted to confirm the findings. Detailed study of the effect of stability and vibration of bearings was taken up. The maximum rotational speed obtained was 200,000 rpm.Practical implicationsThe outcome may help the designers, researchers and manufacturers of these components.Originality/valueAlthough manufacturers design and develop the bearings of turboexpanders for their production, no academic literature has been available for this purpose until now.

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Plusquellic, D. F., T. M. Korter, G. T. Fraser, R. J. Lavrich, E. C. Benck, C. R. Bucher, A. R. Hight Walker, and J. L. Domenech. "Continuous-Wave Terahertz Spectroscopy of Plasmas and Biomolecules." International Journal of High Speed Electronics and Systems 13, no. 04 (December 2003): 1287–306. http://dx.doi.org/10.1142/s0129156403002174.

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Continuous-wave linear-absorption spectroscopy based on THz radiation generated by solid-state photomixers has been applied to the investigation of the dynamics of biomolecules in polyethylene matrices and to line shape studies of HF for diagnostics of semiconductor etching plasmas. The THz spectra of biotin and myoglobin have been obtained using a variable-temperature, cryogenic sampling system. The spectrum of biotin displays a small number of discrete absorptions over the temperature range from 4.2 K to room temperature while the spectrum of myoglobin has no obvious resonance structure at the >10% fractional absorption level. Spectral predictions from the lowest energy ab initio conformations of biotin are in poor agreement with experiment, suggesting the need to include condensed-phase environmental interactions for qualitative predictions of the THz spectrum. Vibrational anharmonicity is used to model the line shapes that result from drastic changes in vibrational sequence level populations of biotin over this temperature range. Anharmonicity factors (χeωe/ωe) at the levels of 0.1% to 0.8% are obtained from non-linear least squares fits of the observed resonances and illustrate their important for refining model predictions. Application of the photomixer system to line shape studies in etching plasmas has been used to study the formation efficiency and translational temperature of HF at 1.2 THz under different operating conditions. These results will aid in understanding the chemistry of industry-standard fluorocarbon and oxygenated fluorocarbon etching plasmas.

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Han, Fenghui, Zhe Wang, Hefu Zhang, Dongxing Wang, Wenhua Li, and Wenjian Cai. "Experimental Study of Large-Temperature-Range and Long-Period Monitoring for LNG Marine Auxiliary Based on Fiber Bragg Grating Temperature Measurement." Journal of Marine Science and Engineering 9, no. 9 (August 24, 2021): 917. http://dx.doi.org/10.3390/jmse9090917.

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Temperature is a key variable to evaluate the energy consumption and thermodynamic performance of traditional marine auxiliary machinery, chillers and piping systems. In particular, for the cryogenic storage tanks and fuel gas supply systems of LNG ships, explosion-proof and low-temperature-resistance properties bring new challenges to the onboard temperature measurement and monitoring. In order to promote the development of high-performance and safer monitoring systems for LNG ships, this paper adopted fiber Bragg grating (FBG) technology to ensure the measurement safety and accuracy of temperature sensors, and performs a series of experiments in a large temperature range on the chiller, pipeline, and cryogenic storage tank of an LNG ship and their long-term reliabilities. Firstly, the principle and composition of the designed FBG temperature sensors are introduced in detail, and the measurement accuracy and range of different metal-coated optical fibers were tested in a large temperature range and compared against the traditional thermistors. Then, the effects of different operating conditions of the LNG marine chiller system and cryogenic storage tank on the temperature measurements were investigated. In addition, the drift degrees of the optical fibers and industrial thermistors were analyzed to figure out their reliabilities for long-term temperature measurements. The results showed that for the long-period (16 months) monitoring of LNG ships in a large temperature range (105–315 K) under different shipping conditions, the optical temperature measurement based on FBG technology has sufficient accuracy and dynamic sensitivity with a higher safety than the traditional thermoelectric measurement. Besides, the ship vibration, ambient humidity, and great temperature changes have little impact on its measurement reliability and drifts. This research can provide references and technical supports to the performance testing systems of LNG ships and other relevant vessels with stricter safety standards.

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Oliver, V. I., Yu O. Prusman, and A. V. Gromov. "Stand and method of measuring the vibration acceleration parameters of gas cryogenic machines." Chemical and Petroleum Engineering 25, no. 6 (June 1989): 338–39. http://dx.doi.org/10.1007/bf01156215.

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Othman, Mohammad M., Sherzad A. Taha, and Saeed O. Ibrahim. "Electron Swarm Parameters and Dielectric Properties of the Superconducting Binary Mixtures of He-H2." Alinteri Journal of Agriculture Sciences 36, no. 1 (June 22, 2021): 420–32. http://dx.doi.org/10.47059/alinteri/v36i1/ajas21063.

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In this study, the electron energy distribution function EEDF, the electron swarm parameters, the effective ionization coefficients, and the critical field strength (dielectric strength) in binary He-H2 gas mixture which used as cryogenic for high-temperature superconducting power application, are evaluated by using two-term approximation of the Boltzmann equation over the range of E/N ( the electric field to gas density) from 1 to 100 Td ( 1 Td=10-17 Vcm2) at temperature 77 K and pressure 2MPa, taking into account elastic and inelastic cross-section. Using the calculated EEDF, the electron swarm parameters (electron drift velocity, mean electron energy, diffusion coefficient, electron mobility, ionization and attachment coefficient) are calculated. At low reduced electric field E/N, the EEDF close Maxwellian distribution, at high E/N, due to vibrational excitation of H2 the calculated distribution function is non-Maxwellian. Besides, in the He-H2 mixture, it is found that increasing small amount of H2 enhances to shift the tail of EEDF to the lower energy region, the reduced ionization coefficient α/N. reduced effective ionization coefficient (α-η)/N) decreases, while, reduced attachment coefficient η/N, reduced critical electric field strength (E/N)crt. and critical electric field Ecrt. Increases, because of hydrogen’s large ionization cross-sections. The dielectric strength of 5% H2 in mixture is in good agreement with experimental values, it is found that dielectric strength depend on pressure and temperature. The electron swarm parameters in pure gaseous helium (He) and hydrogen (H2), in satisfying agreement with previous available theoretical and experimental values. The validity of the calculated values has been confirmed by two-term approximation of the Boltzmann equation analysis.

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LIGI, C., M. BASSAN, S. BERTOLUCCI, B. BUONOMO, E. COCCIA, G. DELLE MONACHE, S. D'ANTONIO, et al. "RAP — ACOUSTIC DETECTION OF PARTICLES: FIRST RESULTS AT 4.2 K." International Journal of Modern Physics A 20, no. 29 (November 20, 2005): 7054–56. http://dx.doi.org/10.1142/s0217751x05030806.

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RAP (Rivelazione Acustica di Particelle) is a small cylindrical aluminum bar (l = 500 mm , d = 181.7 mm ) placed at the DAΦNE Beam Test Facility, where it is hit by a 510 MeV electron beam, coming from the DAΦNE Linac. Aim of the experiment is to measure the mechanical vibrations of the bar caused by the interaction with the beam. On June, 2004 RAP successfully collected data for the first time at cryogenic temperature. Several runs at different temperatures (4.5, 70 and 273 K) have been performed and a number of shots in normal-conducting state of the bar were detected. The preliminary results are in good agreement with the Thermo-Acoustic Model. In the next months the mounting of a dilution refrigerator and the data taking of the bar in the superconducting state (T = 100 mK ) have been planned.

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BELOSLUDOV, V. R., O. S. SUBBOTIN, R. V. BELOSLUDOV, H. MIZUSEKI, Y. KAWAZOE, and J. KUDOH. "THERMODYNAMICS AND HYDROGEN STORAGE ABILITY OF BINARY HYDROGEN + HELP GAS CLATHRATE HYDRATE." International Journal of Nanoscience 08, no. 01n02 (February 2009): 57–63. http://dx.doi.org/10.1142/s0219581x0900589x.

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Storage of hydrogen as hydrogen hydrate is a promising alternative technology to liquefied hydrogen at cryogenic temperatures or compressed hydrogen at high pressures. In this paper, computer simulation is performed based on the solid solution theory of clathrates of van der Waals and Platteeuw with some modifications that include in particular the account of multiple cage occupancies and host relaxation. The quasiharmonic lattice dynamics method employed here gives the free energy of clathrate hydrate to first order in the anharmonicity of intermolecular potential and permits to take into account quantum zero-point vibration of host lattice and hydrogen in the cages. It is employed to study the thermodynamic functions of binary (mixed) H 2– CH 4 hydrates of cubic structure II (sII) and hexagonal structure H (sH). It is shown that at divariant equilibrium "gas phase–gas hydrate" with increasing pressure the filling of large cavities by hydrogen proceeds gradually from single filling to the maximal number of hydrogen molecules in clusters included in large cages (four in sII and five in sH) preserving stability of the hydrogen–methane hydrates sII and sH. The results show that mass fraction of hydrogen in the mixed sH hydrate is significantly lower than in the mixed sII hydrate. Pressure of monovariant equilibrium " IceI h–gas phase–mixed sII hydrate" with increasing methane concentration in the gas phase lowers in comparison with the pressure of pure hydrogen hydrate formation. For the mixed hydrogen + methane sH hydrates, it was demonstrated that thermodynamic stability depends on the filling degree of small cavities by methane molecules and stability area shifts to lower pressure with increasing filling.

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Sabol, Rachel, Hakm Murad, Matthew Burow, Damir Khismatullin, and Bruce Bunnell. "2070 High-intensity focused ultrasound (HIFU) can be used synergistically with tamoxifen to overcome resistance in preclinical and patient derived xenograft models." Journal of Clinical and Translational Science 2, S1 (June 2018): 14. http://dx.doi.org/10.1017/cts.2018.80.

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OBJECTIVES/SPECIFIC AIMS: The goal of this study is to evaluate a potential strategy to overcome tamoxifen (tam) resistance by using tam in combination with high-intensity focused ultrasound (HIFU). Tam is the most commonly used anti-cancer therapeutic agent in estrogen receptor positive (ER+) breast cancer (BC) which accounts for ~70% of BC cases. Tam treatment decreases a woman’s risk of recurrence by 50%; however, BC that is initially responsive to tam often develops resistance. METHODS/STUDY POPULATION: HIFU deposits acoustic energy locally to a cancerous region, which induces strong vibrations of molecules inside and outside of the cells. The resulting absorption causes rapid heating and mechanical disruption. This clinically relevant, noninvasive, and nonionizing physical force modality, has been shown to synergistically enhance chemical anticancer therapies. RESULTS/ANTICIPATED RESULTS: In this study we found that treatment of MCF7 cells with HIFU and tam has additive antiproliferative effects and mediates increased cell death. Additionally, we used tam resistant (TR) MCF7 cells that had been exposed to low-dose tam over time until they acquired resistance. When MCF7 TR are treated with tam there is no change in viability; however, treatment with HIFU in combination with tam decreased viability of both MCF7 and MCF7 TR to 19% and the viability of the cell lines was indistinguishable. We next evaluated the effect on MCF7 Y537S mutant ESR1, where ER is mutated to be constitutively active. Treatment of MCF7 Y537S had no significant decrease in viability of combination therapy compared with viability after HIFU alone. Analysis of ERalpha gene expression showed that HIFU treatment increased ERalpha expression in MCF7 TR cells, thus resensitizing these cells to tam and allowing these therapies to work synergistically. Our team developed a system to evaluate the potential of this combination of therapies in a patient-derived xenografts (PDX) model. PDX have emerged as a novel translational tool for cancer research with the potential to more accurately recapitulate the molecular and behavioral aspects of cancer. The WHIM20 PDX is a tamoxifen resistant tumor where the patient developed the Y537S mutation in ESR1. Ex vivo experiments on PDX tumor pieces demonstrated that combination therapy of HIFU and tam work synergistically to increase cell death of these tumors. Further, cryogenic-scanning electron microscopy was utilized to directly demonstrate the physical disruption to both cellular and tumor microenvironment post exposure to combination treatment. DISCUSSION/SIGNIFICANCE OF IMPACT: These studies present a novel translational strategy to overcome tamoxifen resistance in ER+BC.

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Dinu, Dennis F., Maren Podewitz, Hinrich Grothe, Thomas Loerting, and Klaus R. Liedl. "On the synergy of matrix-isolation infrared spectroscopy and vibrational configuration interaction computations." Theoretical Chemistry Accounts 139, no. 12 (November 9, 2020). http://dx.doi.org/10.1007/s00214-020-02682-0.

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AbstractThe key feature of matrix-isolation infrared (MI-IR) spectroscopy is the isolation of single guest molecules in a host system at cryogenic conditions. The matrix mostly hinders rotation of the guest molecule, providing access to pure vibrational features. Vibrational self-consistent field (VSCF) and configuration interaction computations (VCI) on ab initio multimode potential energy surfaces (PES) give rise to anharmonic vibrational spectra. In a single-sourced combination of these experimental and computational approaches, we have established an iterative spectroscopic characterization procedure. The present article reviews the scope of this procedure by highlighting the strengths and limitations based on the examples of water, carbon dioxide, methane, methanol, and fluoroethane. An assessment of setups for the construction of the multimode PES on the example of methanol demonstrates that CCSD(T)-F12 level of theory is preferable to compute (a) accurate vibrational frequencies and (b) equilibrium or vibrationally averaged structural parameters. Our procedure has allowed us to uniquely assign unknown or disputed bands and enabled us to clarify problematic spectral regions that are crowded with combination bands and overtones. Besides spectroscopic assignment, the excellent agreement between theory and experiment paves the way to tackle questions of rather fundamental nature as to whether or not matrix effects are systematic, and it shows the limits of conventional notations used by spectroscopists.

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Clark, Arthur E. "High Power Magnetostrictive Materials from Cryogenic Temperatures to 250 C." MRS Proceedings 360 (1994). http://dx.doi.org/10.1557/proc-360-171.

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AbstractThe rare earths, both in elemental form and in compounds, are widely known as possessing many extraordinary magnetic properties. In this paper, we focus on the huge magnetically induced displacements (magnetostrictions) based upon the element terbium. A proper balance of magnetic anisotropy and magnetostriction, plus a proper choice of crystal axes lead to materials which can switch large quantities of energy between the internal (magnetic) and external (mechanical) states with the application of small triggering magnetic fields. Power densities 2000 times those of conventional magnetostrictive materials and 10-20 times those of typical piezoceramics are available. These materials are particularly valuable for smart systems where large energy transduction is needed such as active structure stiffening and active vibration control.

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Temnov, A. N., and Ko Ko Win. "Theoretical and experimental studies of vibrations of the solid half-cylinder having a cavity filled with a layered fluid." Engineering Journal: Science and Innovation, no. 5 (89) (May 2019). http://dx.doi.org/10.18698/2308-6033-2019-5-1883.

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Further exploration of outer space is not possible without energy industrialization. For the industrialization of outer space, Russian and American experts are considering the possibility of creating orbital refueling stations and space refueling stations for future flights to the Moon, Mars and other planets. The proposed article presents the formulation of the problem, the solutions and the results of studies of the dynamic characteristics and stability of small oscillations of a solid, simulating a space tanker, whose fuel tank contains a cryogenic liquid. A distinctive feature of a cryogenic liquid is the low temperatures and various densities of fluid particles observed in the processes of storage and operation, which greatly complicates the study of hydrodynamic problems. In the article, the cryogenic fluid is modeled by layers of immiscible liquids. In the work, the equations of motion of a rigid body with a cavity containing three immiscible incompressible ideal liquids and performing a plane motion are obtained. The formulation of the problem of small oscillations and stability of motion of a rigid body with a cavity filled with such a layered fluid is given. The areas of stability of the motion of a solid semi-cylinder with a cylindrical cavity filled with three immiscible liquids are investigated. The article also presents the results of an experimental study of oscillations of a half-cylinder with two immiscible liquids.

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Wang, Hongchang, Shuyun Jiang, and Zupei Shen. "The Dynamic Analysis of an Energy Storage Flywheel System With Hybrid Bearing Support." Journal of Vibration and Acoustics 131, no. 5 (September 10, 2009). http://dx.doi.org/10.1115/1.3147128.

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Active magnetic bearings and superconducting magnetic bearings were used on a high-speed flywheel energy storage system; however, their wide industrial acceptance is still a challenging task because of the complexity in designing the elaborate active control system and the difficulty in satisfying the cryogenic condition. A hybrid bearing consisting of a permanent magnetic bearing and a pivot jewel bearing is used as the support for the rotor of the energy storage flywheel system. It is simple and has a long working life without requiring maintenance or an active control system. The two squeeze film dampers are employed in the flywheel system to suppress the lateral vibration, to enhance the rotor leaning stability, and to reduce the transmitted forces. The dynamic equation of the flywheel with four degrees of complex freedom is built by means of the Lagrange equation. In order to improve accuracy, the finite element method is utilized to solve the Reynolds equation for the dynamic characteristics of the squeeze film damper. When the calculated unbalance responses are compared with the test responses, they indicate that the dynamics model is correct. Finally, the effect of the squeeze film gap on the transmitted force is analyzed, and the appropriate gap should be selected to cut the energy loss and to control vibration of the flywheel system.

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Lohn, Andrew J., Milo Holt, Noel Dawson, and Nobuhiko P. Kobayashi. "Ensemble Effects on the Optical Properties of Indium Phosphide Nanowires at Various Temperatures." MRS Proceedings 1258 (2010). http://dx.doi.org/10.1557/proc-1258-p04-14.

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AbstractEnsembles of indium phosphide nanowires were grown on amorphous quartz substrates and their optical properties were examined at various cryogenic temperatures. Complex dynamics result from the large areal densities, random orientation, combination of both zincblende and wurtzite phases, and the geometries of the nanowires. Those complex dynamics are discussed in relation to their effect on the temperature dependence of photoluminescence and Raman spectroscopy. Five peaks are found to exist in the photoluminescence spectra at low temperatures which are attributed to radiative recombinations associated with quantum confined zinc blende, quantum confined excitons in zinc blende, quantum confined wurtzite, excitons in bulk zinc blende and impurity states. An energy transfer mechanism between two types of radiative recombinations among the five is proposed to explain intensity variations and the temperature dependence of the PL peaks is discussed. The Raman spectra is observed to have peaks created by a combination of zinc blende and wurtzite vibrational modes which is explained by folding the phonon dispersion.

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Journal articles on the topic 'Vibrational energy][Cryogenics'

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