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Journal articles on the topic 'Relaxation time'

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Author: Grafiati

Published: 4 June 2021

Last updated: 25 May 2024

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1

Sun, Nanjian, and Charles E. Frazier. "Time/temperature equivalence in the dry wood creep response." Holzforschung 61, no. 6 (November 1, 2007): 702–6. http://dx.doi.org/10.1515/hf.2007.114.

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Abstract Rheology of wood molecular and supramolecular organization has mostly been conducted with dynamic methods, and the application of time/temperature equivalence typically requires plasticizers to observe segmental relaxation. Dry wood rheology offers the experimental advantage of easy moisture control, but only weak secondary relaxations are observed with dynamic methods. Static methods allow for the longer relaxation times in glassy polymers, and these relaxations are strongly stimulated by lower less damaging temperatures. This study describes the application of creep mode time/temperature equivalence to dry yellow-poplar (Liriodendron tulipifera) and southern yellow pine (Pinus spp.). It was found that time/temperature equivalence was valid from 10–170°C, but only for specimens that received a prior 30-min thermal treatment (with minor desiccation) in the range of 100–170°C. The two woods exhibited clear differences in the temperature dependence of the dry wood creep relaxation, and in the sensitivity to free volume manipulation. These findings are believed to reflect polymer structural differences in hardwoods and softwoods indicating that creep mode time/temperature studies of dry wood may be useful for the analysis of xylem polymer behavior.

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2

Suh, Daewoong, and Reinhold H. Dauskardt. "Mechanical Relaxation Time Scales in a Zr–Ti–Ni–Cu–Be Bulk Metallic Glass." Journal of Materials Research 17, no. 6 (June 2002): 1254–57. http://dx.doi.org/10.1557/jmr.2002.0188.

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The relaxation time scales in a commercial-grade Zr41.25Ti13.75Ni10Cu12.5Be22.5 (at.%) bulk metallic glass were examined using transient and dynamic mechanical experiments. The viscoelastic and sub-Tg relaxations were well described by the Kohlrausch–Williams–Watts relaxation function. A large activation energy (4.0 eV) and small nonexponentiality parameter (approximately 0.5) were observed for viscoelastic relaxation above Tg consistent with the cooperative nature of atomic movements leading ultimately to viscous flow. Conversely, a small activation energy (0.1 eV) and large nonexponentiality parameter (approximately 0.9) were observed for the sub-Tg relaxation suggesting localized atomic adjustments which may involve different structural units or mechanisms. The glass transition was manifested as a decoupling of the sub-Tg and viscoelastic relaxation. The resulting transition temperature determined at a selected time scale was in agreement with the value obtained from calorimetric studies.

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3

Sudo, Seiichi, Naoki Shinyashiki, Yusuke Kitsuki, and Shin Yagihara. "Dielectric Relaxation Time and Relaxation Time Distribution of Alcohol−Water Mixtures." Journal of Physical Chemistry A 106, no. 3 (January 2002): 458–64. http://dx.doi.org/10.1021/jp013117y.

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4

Kaldoudi, Eleni, and Steve C. R. Williams. "Relaxation time measurements in NMR imaging. Part I: Longitudinal relaxation time." Concepts in Magnetic Resonance 5, no. 3 (July 1993): 217–42. http://dx.doi.org/10.1002/cmr.1820050303.

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5

Shan, Xiaowen, Xuhui Li, and Yangyang Shi. "A multiple-relaxation-time collision model by Hermite expansion." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2208 (August 30, 2021): 20200406. http://dx.doi.org/10.1098/rsta.2020.0406.

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The Bhatnagar–Gross–Krook (BGK) single-relaxation-time collision model for the Boltzmann equation serves as the foundation of the lattice BGK (LBGK) method developed in recent years. The description of the collision as a uniform relaxation process of the distribution function towards its equilibrium is, in many scenarios, simplistic. Based on a previous series of papers, we present a collision model formulated as independent relaxations of the irreducible components of the Hermite coefficients in the reference frame moving with the fluid. These components, corresponding to the irreducible representation of the rotation group, are the minimum tensor components that can be separately relaxed without violating rotation symmetry. For the 2nd, 3rd and 4th moments, respectively, two, two and three independent relaxation rates can exist, giving rise to the shear and bulk viscosity, thermal diffusivity and some high-order relaxation process not explicitly manifested in the Navier–Stokes-Fourier equations. Using the binomial transform, the Hermite coefficients are evaluated in the absolute frame to avoid the numerical dissipation introduced by interpolation. Extensive numerical verification is also provided. This article is part of the theme issue ‘Progress in mesoscale methods for fluid dynamics simulation’.

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6

Stephanovich, V. A., M. D. Glinchuk, and B. Hilczer. "Relaxation time distribution function." Ferroelectrics 240, no. 1 (January 2000): 1495–505. http://dx.doi.org/10.1080/00150190008227975.

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7

Ikeda, Harukuni. "Relaxation time below jamming." Journal of Chemical Physics 153, no. 12 (September 28, 2020): 126102. http://dx.doi.org/10.1063/5.0024042.

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8

Paulson, K. S., S. Jouravleva, and C. N. McLeod. "Dielectric relaxation time spectroscopy." IEEE Transactions on Biomedical Engineering 47, no. 11 (2000): 1510–17. http://dx.doi.org/10.1109/10.880103.

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9

Ristaniemi, Aapo, Dristi Regmi, Diponkor Mondal, Jari Torniainen, Petri Tanska, Lauri Stenroth, Mikko A. J. Finnilä, Juha Töyräs, and Rami K. Korhonen. "Structure, composition and fibril-reinforced poroviscoelastic properties of bovine knee ligaments and patellar tendon." Journal of The Royal Society Interface 18, no. 174 (January 2021): 20200737. http://dx.doi.org/10.1098/rsif.2020.0737.

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Tissue-level stress-relaxation of ligaments and tendons in the toe region is characterized by fast and long-term relaxations and an increase in relaxation magnitude with strain. Characterizing the compositional and structural origins of these phenomena helps in the understanding of mechanisms of ligament and tendon function and adaptation in health and disease. A three-step tensile stress-relaxation test was conducted on dumbbell-shaped pieces of bovine knee ligaments and patellar tendon (PT) ( n = 10 knees). Their mechanical behaviour was characterized by a fibril-reinforced poroviscoelastic material model, able to describe characteristic times and magnitudes of fast and long-term relaxations. The crimp angle and length of tissues were measured with polarized light microscopy, while biochemical contents were determined by colorimetric biochemical methods. The long-term relaxation time was longer in the anterior cruciate ligament (ACL) and PT compared with collateral ligaments ( p < 0.05). High hydroxyproline content predicted greater magnitude and shorter time of both fast and long-term relaxation. High uronic acid content predicted longer time of long-term relaxation, whereas high crimp angle predicted higher magnitude of long-term relaxation. ACL and PT are better long-term stabilizers than collateral ligaments. The long-term relaxation behaviour is affected or implied by proteoglycans and crimp angle, possibly relating to slow structural reorganization of the tissue.

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10

Holloway, R. H., R. Penagini, and A. C. Ireland. "Criteria for objective definition of transient lower esophageal sphincter relaxation." American Journal of Physiology-Gastrointestinal and Liver Physiology 268, no. 1 (January 1, 1995): G128—G133. http://dx.doi.org/10.1152/ajpgi.1995.268.1.g128.

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We developed and evaluated objective manometric criteria that define transient lower esophageal sphincter (LES) relaxation. In 23 normal subjects and 9 patients with gastroesophageal reflux disease, systematic analysis of swallow-induced LES relaxation showed that dry swallows preceded LES relaxation by a median of 1.4 s. The relaxation rate was always > 1 mmHg/s, the relaxation nadir always occurred within 7 s, and the duration of relaxation was < 9 s. During concurrent esophageal manometry and pH monitoring, 104 reflux episodes associated with a LES pressure fall that was not related to swallowing were identified and the pressure falls classified as transient LES relaxations or not by visual recognition. LES pressure was always < or = 2 mmHg at time of reflux, and relaxation was significantly longer than for swallow-induced LES relaxation. Of 88 pressure falls classified visually as transient LES relaxations, 90% reached nadir pressure within 7 s at a rate of > 1 mmHg/s. Sixteen pressure falls were classified as a gradual downward drift in LES pressure, which in 15 cases was < 1 mmHg/s. Based on the analysis, transient LES relaxation can be defined by 1) absence of swallowing for 4 s before to 2 s after the onset of LES relaxation, 2) relaxation rate of > or = 1 mmHg/s, 3) time from onset to complete relaxation of < or = 10 s, and 4) nadir pressure of < or = 2 mmHg.(ABSTRACT TRUNCATED AT 250 WORDS)

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11

Yu, Peng, Cheng Fang, and Brian Williams. "Resolving Uncontrollable Conditional Temporal Problems Using Continuous Relaxations." Proceedings of the International Conference on Automated Planning and Scheduling 24 (May 11, 2014): 341–48. http://dx.doi.org/10.1609/icaps.v24i1.13623.

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Uncertainty is commonly encountered in temporal scheduling and planning problems, and can often lead to over-constrained situations. Previous relaxation algorithms for over-constrained temporal problems only work with requirement constraints, whose outcomes can be controlled by the agents. When applied to uncontrollable durations, these algorithms may only satisfy a subset of the random outcomes and hence their relaxations may fail during execution. In this paper, we present a new relaxation algorithm, Conflict-Directed Relaxation with Uncertainty (CDRU), which generates relaxations that restore the controllability of conditional temporal problems with uncontrollable durations. CDRU extends the Best-first Conflict-Directed Relaxation (BCDR) algorithm to uncontrollable temporal problems. It generalizes the conflict-learning process to extract conflicts from strong and dynamic controllability checking algorithms, and resolves the conflicts by both relaxing constraints and tightening uncontrollable durations. Empirical test results on a range of trip scheduling problems show that CDRU is efficient in resolving large scale uncontrollable problems: computing strongly controllable relaxations takes the same order of magnitude in time compared to consistent relaxations that do not account for uncontrollable durations. While computing dynamically controllable relaxations takes two orders of magnitude more time, it provides significant improvements in solution quality when compared to strongly controllable relaxations.

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12

Mamontov, Eugene, and Piotr Zolnierczuk. "Determining the relaxation time from a temperature-dependent scan of the neutron spin-echo signal amplitude." EPJ Web of Conferences 272 (2022): 01014. http://dx.doi.org/10.1051/epjconf/202227201014.

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Temperature-dependent scans of the neutron scattering intensity are commonly employed in high energy-resolution quasielastic measurements. Besides serving as a useful diagnostic tool for identifying the temperature range that could give rise to a measurable relaxation signal, such scans of the “elastic” (resolution-defined) intensity could be employed for determining the temperature at which the relaxation time in the system becomes equal to the resolution-defined characteristic time of the spectrometer measurement. This is a model-independent alternative to the “traditional” approach, when, at a given measurement temperature, the relaxation time in the system is obtained from fitting the full dynamic spectra with a model scattering function. Here we introduce the temperature-dependent scan of the neutron spin-echo signal amplitude. Using a well-characterized system with a complex relaxation pattern, we demonstrate that the relaxation time obtained from the approach proposed herein maps well on the previous “traditionally” measured relaxation times. Thus, despite monitoring a different variable (neutron spin-echo signal amplitude vs. neutron scattering intensity), the benefits of the model-free temperature-dependent scan approach, traditionally utilized in neutron time-of-flight and backscattering experiments, can be extended to measurements of the very slow relaxations assessable only by high-resolution neutron spin-echo.

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13

Oliveira, L. C., H. A. Gomide, and R. S. L. Rade. "Primary creep behaviour of polyester resins from multiple relaxation curves." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 217, no. 12 (December 1, 2003): 1301–13. http://dx.doi.org/10.1243/095440603322769947.

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Typical primary creep behaviour of a viscoelastoplastic material is shown when varying the temperature and the time rate of strain (of a previous tension). The creep behaviour is obtained from the tension test with multiple relaxations, where a numerical procedure is used in order to obtain creep curves from a series of relaxation curves. This test methodology allows interrelated tension, relaxation and creep behaviours to be obtained from one single test. The materials tested are proportional to the weight mixtures of rigid/flexible polyester resins with hardeners, generally used as model materials in photomechanics. With the increase in temperature, there is a decrease in the time needed to reach a given creep strain. The time rate of the strain, used in the tensions prior to the relaxations, has a considerable influence on the beginning of the relaxations. Since the creep curve is obtained from these relaxations, the rate of strain is shown to have an influence on creep behaviour, depending on the portion of the relaxation curve from where values are taken for calculation of creep.

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14

Guo, Jin Quan, Wu Zhou Meng, Fei Li, and Li Xin Wang. "Creep Prediction From Stress Relaxation Coupled With Equivalent Relaxation Rate." Applied Mechanics and Materials 644-650 (September 2014): 1382–85. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.1382.

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Several stress relaxation and creep tests of high temperature material are performed. According to the characteristics of stress relaxations and the superposition equation of diffusion and Maxwell equations of two stages, equivalent relaxation time and equivalent relaxation rate are proposed. Considering equivalent relaxation rate as the creep rate under constant stress, the relaxation-creep conversion model is built up and presented. Then the steady-state creep curve and creep rate are calculated. The results show that the numerical results are in good agreement with the experimental data. It indicates that equivalent relaxation rate can be employed for the analysis of steady-state creep rate. The conversion model and method can be used to design the creep strength and predict the life of the component at high temperature.

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15

Bartenev, G. M., and M. V. Karasev. "Relaxational transitions and discontinuous relaxation time spectra of cis-polyisoprene." Polymer Science U.S.S.R. 28, no. 11 (January 1986): 2742–50. http://dx.doi.org/10.1016/0032-3950(86)90314-x.

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16

Laureckienė, Ginta, and Rimvydas Milašius. "Behaviour of Long-Lasting Stress Relaxation of Various Types of Yarns." Autex Research Journal 17, no. 4 (December 20, 2017): 379–85. http://dx.doi.org/10.1515/aut-2017-0017.

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Abstract The main goal of this researcher is estimating of the possibility of long-lasting (even until 200,000 s) stress relaxation by empirical investigation, which was performed for a few thousands of seconds. The empirical investigations of longlasting stress relaxation of different types of yarns (multifilament polyester, cotton and woollen) at different levels of elongation, i.e. at 3%, 5%, 7% and 10%, were carried out. The method of long-lasting relaxation behaviour prediction by the break-point of relaxation rate as well as the linear dependence of second part of relaxation were used. It was found that the behaviour of relaxation can be described using time logarithmic scale by two straight lines, and the value of stress relaxation in long time period could be estimated by the second line. The break-point of relaxation rate of all kinds of yarns occurs in the area of 100-200 s after relaxations started. The obtained results showed that the place of relaxation break-point depends on the level of elongation but does not depend on the type of yarns.

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17

Floudas, G., G. Fytas, and I. Alig. "Brillouin scattering from bulk polybutadiene: distribution of relaxation times versus single relaxation time approach." Polymer 32, no. 13 (January 1991): 2307–11. http://dx.doi.org/10.1016/0032-3861(91)90065-q.

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18

Kumar-Krishnan, Siva, Evgen Prokhorov, and Gabriel Luna-Barcenas. "Molecular relaxation in Chitosan films in GHz frequency range." MRS Proceedings 1613 (2014): 83–88. http://dx.doi.org/10.1557/opl.2014.162.

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ABSTRACTThe molecular relaxations behavior of chitosan (CS) films in the wide frequency range of 0.1-3x109 Hz (by using three different impedance analyzers) have been investigated in the temperature range of -100C to 120°C using Dielectric Spectroscopy (DS). Additionally to the low frequency molecular relaxations such as α and β relaxations, for the first time, high frequency (1-3 GHz) relaxation process has been observed in the chitosan films. This relaxation exhibits Arrhenius-type dependence in the temperature range of -100 C to 54°C with negative activation energy -2.7 kJ/mol. At temperatures above 54°C, the activation energy changes from -2.7 kJ/mol to +4.4 kJ/mol. Upon cooling, the activation energy becomes negative again with a value of -1.2 kJ/mol. The bound water between chitosan molecules strongly modifies molecular motion and the relaxation spectrum, giving rise to a new relaxation at the frequency at ca. 1 GHz. In situ FTIR analysis has shown that this relaxation related to the changes in vibration of the –OH, NH and –CO functional groups.

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19

Fujisaki, Hiroshi, Yong Zhang, and JOHN E. STRAUB. "1SD04 Time scales to attain local ergodicity through vibrational relaxation in proteins." Seibutsu Butsuri 45, supplement (2005): S6. http://dx.doi.org/10.2142/biophys.45.s6_2.

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20

Matsumoto, Kazuyuki, and Takayuki Abe. "Nuclear Relaxation Time of Solid3He." Progress of Theoretical Physics 125, no. 2 (February 2011): 375–93. http://dx.doi.org/10.1143/ptp.125.375.

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21

Torsello, Andrea, and Marcello Pelillo. "Continuous-time relaxation labeling processes." Pattern Recognition 33, no. 11 (November 2000): 1897–908. http://dx.doi.org/10.1016/s0031-3203(99)00174-0.

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22

Macháček, Martin. "Dynamical systems with relaxation time." Journal of Statistical Physics 47, no. 5-6 (June 1987): 949–52. http://dx.doi.org/10.1007/bf01206169.

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23

Belikov, A. E., I. Yu Solov'ev, G. I. Sukhinin, and R. G. Sharafutdinov. "Rotational relaxation time of nitrogen." Journal of Applied Mechanics and Technical Physics 29, no. 5 (1989): 630–36. http://dx.doi.org/10.1007/bf00857905.

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24

Gadzhialiev, M. M., Z. Sh Pirmagomedov, and T. N. Efendieva. "Electron Relaxation Time in InAs." Russian Physics Journal 60, no. 12 (April 2018): 2241–42. http://dx.doi.org/10.1007/s11182-018-1353-2.

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25

Nagao, T., and P. M. Vanhoutte. "Hyperpolarization contributes to endothelium-dependent relaxations to acetylcholine in femoral veins of rats." American Journal of Physiology-Heart and Circulatory Physiology 261, no. 4 (October 1, 1991): H1034—H1037. http://dx.doi.org/10.1152/ajpheart.1991.261.4.h1034.

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The contribution of membrane hyperpolarization to endothelium-dependent relaxations induced by acetylcholine was investigated in the femoral vein of the rat using a microelectrode technique and isometric tension recordings. Acetylcholine caused endothelium-dependent relaxations and hyperpolarization in tissues contracted with norepinephrine. The relaxation was sustained during a prolonged exposure to acetylcholine (less than or equal to 10 min). In contrast, the hyperpolarization declined with time. In the presence of nitro-L-arginine, a blocker of nitric oxide synthesis, the relaxation became smaller and transient, whereas the hyperpolarization was not affected. There was a temporal relationship between the relaxation and the hyperpolarization in the presence of nitro-L-arginine, when the two parameters were recorded simultaneously. In tissues contracted with 60 mM K+, in which hyperpolarization could not be observed, acetylcholine caused relaxations and these relaxations were abolished by nitro-L-arginine. The results suggest a contribution of both nitric oxide and membrane hyperpolarization to the endothelium-dependent relaxation induced by acetylcholine in the femoral vein of the rat.

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26

Holubová, J., Z. Černošek, E. Černošková, and M. Liška. "Isothermal structural relaxation: temperature and time dependencies of relaxation parameters." Journal of Non-Crystalline Solids 326-327 (October 2003): 135–40. http://dx.doi.org/10.1016/s0022-3093(03)00392-2.

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27

Viščor, Petr, and N. B. Olsen. "Frequency and time response in relaxation time semiconductors." Journal of Non-Crystalline Solids 90, no. 1-3 (February 1987): 25–28. http://dx.doi.org/10.1016/s0022-3093(87)80377-0.

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28

Kimura, M., T. Endo, K. Sueoka, T. Araiso, K. Mukasa, and H. Takahashi. "Measurement of Spin-Relaxation Times by Time-Resolved Photoluminescence." Journal of the Magnetics Society of Japan 20, no. 2 (1996): 253–56. http://dx.doi.org/10.3379/jmsjmag.20.253.

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29

Paeng, Keewook, Heungman Park, Dat Tien Hoang, and Laura J. Kaufman. "Ideal probe single-molecule experiments reveal the intrinsic dynamic heterogeneity of a supercooled liquid." Proceedings of the National Academy of Sciences 112, no. 16 (March 30, 2015): 4952–57. http://dx.doi.org/10.1073/pnas.1424636112.

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The concept of dynamic heterogeneity and the picture of the supercooled liquid as a mosaic of environments with distinct dynamics that interchange in time have been invoked to explain the nonexponential relaxations measured in these systems. The spatial extent and temporal persistence of these regions of distinct dynamics have remained challenging to identify. Here, single-molecule fluorescence measurements using a probe similar in size and mobility to the host o-terphenyl unambiguously reveal exponential relaxations distributed in time and space and directly demonstrate ergodicity of the system down to the glass transition temperature. In the temperature range probed, at least 200 times the structural relaxation time of the host is required to recover ensemble-averaged relaxation at every spatial region in the system.

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30

Rocha, G. S., G. S. Denicol, M. N. Ferreira, and J. Noronha. "Novel Relaxation Time Approximation: A Consistent Calculation of Transport Coefficients with QCD-inspired Relaxation Times." Acta Physica Polonica B Proceedings Supplement 16, no. 1 (2023): 1. http://dx.doi.org/10.5506/aphyspolbsupp.16.1-a29.

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31

Sukcharoen, Kijvanish, Nitikorn Noraphaiphipaksa, Anat Hasap, and Chaosuan Kanchanomai. "Experimental and Numerical Evaluations of Localized Stress Relaxation for Vulcanized Rubber." Polymers 14, no. 5 (February 23, 2022): 873. http://dx.doi.org/10.3390/polym14050873.

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Vulcanized rubbers are commonly used to provide the energy absorption under compressive deformation from other engineering components. However, if a constant compressive deformation is maintained on rubber, the load response is not constant but decreases with time; i.e., the stress relaxation. A decrease in force response with time of rubber can be experimentally evaluated by the stress relaxation test. In the present work, the localized stress of vulcanized rubber during a compressive stress relaxation test (i.e., ASTM D6147) was evaluated. Hyperelastic behavior was assumed during rapid application of strain, while the viscoelastic behavior was assumed during stress relaxation. Hyperelastic and viscoelastic parameters were experimentally evaluated using a standard specimen. Finite element analysis (FEA) models were applied for the predictions of stress relaxations of rubbers with various geometries and applied strains. FEA results were in good agreement with results of the stress relaxation tests. Localized stresses in rubber during rapid application of compressive strain and stress relaxation were successfully evaluated. The findings can give the localized phenomena of vulcanized rubber during a stress relaxation test, which can be used as a guideline for the design, usage, and improvement of rubber and viscoelastic polymeric components.

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32

Massa, Carlo Andrea, Francesco Puosi, and Dino Leporini. "Fractional Coupling of Primary and Johari–Goldstein Relaxations in a Model Polymer." Polymers 14, no. 24 (December 19, 2022): 5560. http://dx.doi.org/10.3390/polym14245560.

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A polymer model exhibiting heterogeneous Johari–Goldstein (JG) secondary relaxation is studied by extensive molecular-dynamics simulations of states with different temperature and pressure. Time–temperature–pressure superposition of the primary (segmental) relaxation is evidenced. The time scales of the primary and the JG relaxations are found to be highly correlated according to a power law. The finding agrees with key predictions of the Coupling Model (CM) accounting for the decay in a correlation function due to the relaxation and diffusion of interacting systems. Nonetheless, the exponent of the power law, even if it is found in the range predicted by CM (0<ξ<1), deviates from the expected one. It is suggested that the deviation could depend on the particular relaxation process involved in the correlation function and the heterogeneity of the JG process.

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33

Onyshchenko, Volodymyr Fedorovych, L. A. Karachevtseva, and M. I. Karas’. "Photoconductivity Relaxation Time in Macroporous Silicon." Emerging Science Journal 4, no. 3 (June 1, 2020): 192–204. http://dx.doi.org/10.28991/esj-2020-01223.

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Macroporous silicon has found applications in sensors, receivers, integrated microchips and solar cells. In this work, we first showed analytically the photoconductivity relaxation time of in macroporous silicon is determined from a system of two transcendental equations. The analytical description of the photoconductivity relaxation model contains the diffusion equation solution both in single crystal substrate and in an effective medium of macroporous layer, as well as boundary conditions recorded for the surfaces of the layer of macroporous silicon and single crystal substrate. We showed that the photoconductivity relaxation time in macroporous silicon rapidly decreases with increasing macropore depth from 0 to 25 μm and reduced thicknesses of the single crystal substrate from 250 to 0 μm. The photoconductivity recombination time in the sample of macroporous silicon is limited by the diffusion of charge carriers from the substrate to the recombination surfaces in the macroporous layer. The system of transcendental equations that we have found will find application in calculating the relaxation time of photoconductivity in macroporous silicon devices such as sensors, receivers, and solar cells.

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34

Tripodo, Antonio, Francesco Puosi, Marco Malvaldi, Simone Capaccioli, and Dino Leporini. "Coincident Correlation between Vibrational Dynamics and Primary Relaxation of Polymers with Strong or Weak Johari-Goldstein Relaxation." Polymers 12, no. 4 (March 31, 2020): 761. http://dx.doi.org/10.3390/polym12040761.

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The correlation between the vibrational dynamics, as sensed by the Debye-Waller factor, and the primary relaxation in the presence of secondary Johari-Goldstein (JG) relaxation, has been investigated through molecular dynamics simulations. Two melts of polymer chains with different bond length, resulting in rather different strength of the JG relaxation are studied. We focus on the bond-orientation correlation function, exhibiting higher JG sensitivity with respect to alternatives provided by torsional autocorrelation function and intermediate scattering function. We find that, even if changing the bond length alters both the strength and the relaxation time of the JG relaxation, it leaves unaffected the correlation between the vibrational dynamics and the primary relaxation. The finding is in harmony with previous studies reporting that numerical models not showing secondary relaxations exhibit striking agreement with experimental data of polymers also where the presence of JG relaxation is known.

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35

Doss, Karan, Collin J. Wilkinson, Yongjian Yang, Kuo‐Hao Lee, Liping Huang, and John C. Mauro. "Maxwell relaxation time for nonexponential α‐relaxation phenomena in glassy systems." Journal of the American Ceramic Society 103, no. 6 (February 12, 2020): 3590–99. http://dx.doi.org/10.1111/jace.17051.

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36

Tong, Maosong, Li Li, Weinan Wang, and Yizhong Jiang. "Determining capillary-pressure curve, pore-size distribution, and permeability from induced polarization of shaley sand." GEOPHYSICS 71, no. 3 (May 2006): N33—N40. http://dx.doi.org/10.1190/1.2195989.

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An appropriate form of induced polarization (IP) acts as a bridge between the structure of a water-saturated core plug and its transport properties. The induced-polarization decay curves of natural rocks can be modeled as a weighted superposition of exponential relaxations. A singular-value decomposition method makes it possible to transform the induced-polarization decay data of the shaley sands into relaxation-time spectrum, defined as plot of weight versus the relaxation-time constant. We measured the induced-polarization decay curves of core samples from a formation of Daqing oil field using a four-electrode method. The decay curves were transformed to relaxation-time spectra that were used to estimate the capillary-pressure curves, the pore-size distribution, and the permeability of the shaley sands. The results show that salinity ranges from [Formula: see text] have little effect on the IP relaxation-time spectra. A pseudocapillary pressure curve can be derived from the IP relaxation-time spectrum by matching the pseudocapillary curve with that from HgAir. The best-matching coefficients of the studied cores change slightly for the samples. Defined as the value of pressure at which the injected mercury saturation is 5%, entry pressures of the cores can be estimated well from IP-derived capillary-pressure curves. Pore-size distributions generated from induced polarization and mercury capillary-pressure curves are comparable. Permeability can be predicted from IP measurements in the form of [Formula: see text], where [Formula: see text] is the estimated permeability from IP relaxation spectrum in millidarcies (md), [Formula: see text] is the porosity in percentage, and [Formula: see text] is average time constant of IP relaxation-time spectra in millis (ms). The constants and exponents from various rock formations are slightly different.

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37

Bober, Zuzanna, Piotr Bar, Grzegorz Pasternak, Sabina Galiniak, Dorota Bartusik-Aebisher, Rafał Filip, and David Aebisher. "Infliximab MRI relaxation time in solution." European Journal of Clinical and Experimental Medicine 17, no. 1 (2019): 22–25. http://dx.doi.org/10.15584/ejcem.2019.1.4.

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38

Ye, Hong, G. W. Wicks, and P. M. Fauchet. "Hot electron relaxation time in GaN." Applied Physics Letters 74, no. 5 (February 1999): 711–13. http://dx.doi.org/10.1063/1.122995.

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Herkommer, A. M., V. M. Akulin, and W. P. Schleich. "Coherent evolution after the relaxation time." Physical Review A 49, no. 4 (April 1, 1994): 3127–30. http://dx.doi.org/10.1103/physreva.49.3127.

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40

Kiselev, Alexander, Roman Shterenberg, and Andrej Zlatos. "Relaxation enhancement by time-periodic flows." Indiana University Mathematics Journal 57, no. 5 (2008): 2137–52. http://dx.doi.org/10.1512/iumj.2008.57.3349.

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41

Zorn, Reiner. "Logarithmic moments of relaxation time distributions." Journal of Chemical Physics 116, no. 8 (February 22, 2002): 3204–9. http://dx.doi.org/10.1063/1.1446035.

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42

Rocha, Rodrigo P., and José A. Freire. "Relaxation time in disordered molecular systems." Journal of Chemical Physics 142, no. 20 (May 28, 2015): 204109. http://dx.doi.org/10.1063/1.4921691.

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43

Weaver, John B., and Esra Kuehlert. "Measurement of magnetic nanoparticle relaxation time." Medical Physics 39, no. 5 (April 24, 2012): 2765–70. http://dx.doi.org/10.1118/1.3701775.

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44

Fierz, M., K. Siegmann, and M. Aeschlimann. "Electronic relaxation time in metallic nanoparticles." Journal of Aerosol Science 29 (September 1998): S127—S128. http://dx.doi.org/10.1016/s0021-8502(98)00185-2.

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Karim, A., A. Mansour, G. P. Felcher, and T. P. Russell. "Short-time relaxation at polymeric interfaces." Physical Review B 42, no. 10 (October 1, 1990): 6846–49. http://dx.doi.org/10.1103/physrevb.42.6846.

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46

Heinrich, G., and T. A. Vilgis. "Long-time relaxation of polymer networks." Macromolecules 25, no. 1 (January 1992): 404–7. http://dx.doi.org/10.1021/ma00027a062.

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47

Buchel, Alex. "Relaxation time of non-conformal plasma." Physics Letters B 681, no. 2 (October 2009): 200–203. http://dx.doi.org/10.1016/j.physletb.2009.10.007.

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48

Golub, F., L. C. Potter, J. N. Ash, A. Blank, and R. Ahmad. "Estimation of spin-echo relaxation time." Journal of Magnetic Resonance 237 (December 2013): 17–22. http://dx.doi.org/10.1016/j.jmr.2013.09.006.

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49

Campbell, Shannon R., and DeLiang Wang. "Relaxation oscillators with time delay coupling." Physica D: Nonlinear Phenomena 111, no. 1-4 (January 1998): 151–78. http://dx.doi.org/10.1016/s0167-2789(97)80010-3.

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50

Rosenblueth, Javier F., and Richard B. Vinter. "Relaxation procedures for time delay systems." Journal of Mathematical Analysis and Applications 162, no. 2 (December 1991): 542–63. http://dx.doi.org/10.1016/0022-247x(91)90168-y.

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