Zeitschriftenartikel: „Partial phase change“

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GOUN, A. A., und B. YA ZEL'DOVICH. „CHANGE OF PARTIAL POLARIZATION OF A BEAM UNDER PHASE CONJUGATION“. Journal of Nonlinear Optical Physics & Materials 10, Nr. 03 (September 2001): 371–75. http://dx.doi.org/10.1142/s0218863501000711.

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Possible change of the polarization state in the process of propagation is considered theoretically. We were able to suggest a mechanism that allows for a very unusual behavior of the Stokes parameters of the beam. Specially arranged phase conjugation procedure yields the decrease of only one (e.g. ∣ζ3∣∝∣(∣Ex∣2 - ∣Ey∣2)∣) Stokes component, while the degrees of 45%- and circular polarization, ζ1 and ζ2, are not changing at all.

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Braga, Stefania, Alessandro Sanasi, Alessandro Cabrini und Guido Torelli. „Voltage-Driven Partial-RESET Multilevel Programming in Phase-Change Memories“. IEEE Transactions on Electron Devices 57, Nr. 10 (Oktober 2010): 2556–63. http://dx.doi.org/10.1109/ted.2010.2062185.

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Zastawna-Rumin, Anna, Tomasz Kisilewicz und Umberto Berardi. „Novel Simulation Algorithm for Modeling the Hysteresis of Phase Change Materials“. Energies 13, Nr. 5 (05.03.2020): 1200. http://dx.doi.org/10.3390/en13051200.

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Latent heat thermal energy storage (LHTES) using phase change materials (PCM) is one of the most promising ways for thermal energy storage (TES), especially in lightweight buildings. However, accurate control of the phase transition of PCM is not easy to predict. For example, neglecting the hysteresis or the effect of the speed of phase change processes reduces the accuracy of simulations of TES. In this paper, the authors propose a new software module for EnergyPlus™ that aims to simulate the hysteresis of PCMs during the phase change. The new module is tested by comparing simulation results with experimental tests done in a climatic chamber. A strong consistency between experimental and simulation results was obtained, while a discrepancy error of less than 1% was obtained. Moreover, in real conditions, as a result of quick temperature changes, only a partial phase transformation of the material is often observed. The new model also allows the consideration of the case with partial phase changes of the PCM. Finally, the simulation algorithm presented in this article aims to represent a better way to model LHTES with PCM.

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Su, Yifang, Yihang Zhang, Kaifeng Lin, Guanjun Zhao, Qinzheng Yu, Zuoqi Hu und Xiongfei Tao. „Numerical Study on Resistance Change Characteristics of Phase Change Materials“. Advances in Materials Science and Engineering 2021 (06.07.2021): 1–12. http://dx.doi.org/10.1155/2021/7934173.

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Phase change materials are a type of emerging materials whose states will change under certain conditions, which then lead to changes in resistance. To study the characteristics of the phase change materials, a numerical simulation model of the resistive change unit based on the finite element method and the classic nucleation/growth theory is established, while the partial differential equations of electricity and heat conduction and the discrete formula of the finite element are also derived. According to the phase transition process of phase change materials, a crystalline-amorphous simulation model is also proposed in this paper to simulate the electrical and thermal properties and phase transition process of the resistive change unit. Simulations of the resistance change unit under single pulses with different amplitudes and widths as well as the simulations under continuous pulses are conducted in this paper. These results verify the characteristics of resistance change and can provide references for selecting the parameters of the resistance change units.

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Braga, Stefania, Alessandro Cabrini und Guido Torelli. „Transient effects in partial-RESET programming of phase-change memory cells“. Solid-State Electronics 65-66 (November 2011): 250–55. http://dx.doi.org/10.1016/j.sse.2011.06.026.

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Braga, Stefania, Alessandro Cabrini und Guido Torelli. „Experimental Analysis of Partial-SET State Stability in Phase-Change Memories“. IEEE Transactions on Electron Devices 58, Nr. 2 (Februar 2011): 517–22. http://dx.doi.org/10.1109/ted.2010.2090157.

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Stern, Keren, Nicolas Wainstein, Yair Keller, Christopher M. Neumann, Eric Pop, Shahar Kvatinsky und Eilam Yalon. „Sub-Nanosecond Pulses Enable Partial Reset for Analog Phase Change Memory“. IEEE Electron Device Letters 42, Nr. 9 (September 2021): 1291–94. http://dx.doi.org/10.1109/led.2021.3094765.

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Shi, L. P., T. C. Chong, P. K. Tan, X. S. Miao, Y. M. Huang und R. Zhao. „Study of the Partial Crystallization Properties of Phase-Change Optical Recording Disks“. Japanese Journal of Applied Physics 38, Part 1, No. 3B (30.03.1999): 1645–48. http://dx.doi.org/10.1143/jjap.38.1645.

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Peng, Chubing, und Masud Mansuripur. „Partial-response signaling for phase-change optical data storage without electronic equalization“. Applied Optics 41, Nr. 17 (10.06.2002): 3479. http://dx.doi.org/10.1364/ao.41.003479.

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Li, Yang, Yaochen Qin, Liqun Ma und Ziwu Pan. „Climate change: vegetation and phenological phase dynamics“. International Journal of Climate Change Strategies and Management 12, Nr. 4 (06.07.2020): 495–509. http://dx.doi.org/10.1108/ijccsm-06-2019-0037.

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Purpose The ecological environment of the Loess Plateau, China, is extremely fragile under the context of global warming. Over the past two decades, the vegetation of the Loess Plateau has undergone great changes. This paper aims to clarify the response mechanisms of vegetation to climate change, to provide support for the restoration and environmental treatment of vegetation on the Loess Plateau. Design/methodology/approach The Savitsky–Golay (S-G) filtering algorithm was used to reconstruct time series of moderate resolution imaging spectroradiometer (MODIS) 13A2 data. Combined with trend analysis and partial correlation analysis, the influence of climate change on the phenology and enhanced vegetation index (EVI) during the growing season was described. Findings The S-G filtering algorithm is suitable for EVI reconstruction of the Loess Plateau. The date of start of growing season was found to gradually later along the Southeast–Northwest direction, whereas the date of the end of the growing season showed the opposite pattern and the length of the growing season gradually shortened. Vegetation EVI values decreased gradually from Southeast to Northwest. Vegetation changed significantly and showed clear differentiation according to different topographic factors. Vegetation correlated positively with precipitation from April to July and with temperature from August to November. Originality/value This study provides technical support for ecological environmental assessment, restoration of regional vegetation coverage and environmental governance of the Loess Plateau over the past two decades. It also provides theoretical support for the prediction model of vegetation phenology changes based on remote sensing data.

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Pineda-Sanchez, Manuel, Ruben Puche-Panadero, Javier Martinez-Roman, Angel Sapena-Bano, Martin Riera-Guasp und Juan Perez-Cruz. „Partial Inductance Model of Induction Machines for Fault Diagnosis“. Sensors 18, Nr. 7 (18.07.2018): 2340. http://dx.doi.org/10.3390/s18072340.

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The development of advanced fault diagnostic systems for induction machines through the stator current requires accurate and fast models that can simulate the machine under faulty conditions, both in steady-state and in transient regime. These models are far more complex than the models used for healthy machines, because one of the effect of the faults is to change the winding configurations (broken bar faults, rotor asymmetries, and inter-turn short circuits) or the magnetic circuit (eccentricity and bearing faults). This produces a change of the self and mutual phase inductances, which induces in the stator currents the characteristic fault harmonics used to detect and to quantify the fault. The development of a machine model that can reflect these changes is a challenging task, which is addressed in this work with a novel approach, based on the concept of partial inductances. Instead of developing the machine model based on the phases’ coils, it is developed using the partial inductance of a single conductor, obtained through the magnetic vector potential, and combining the partial inductances of all the conductors with a fast Fourier transform for obtaining the phases’ inductances. The proposed method is validated using a commercial induction motor with forced broken bars.

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Peng, Chubing, und M. Mansuripur. „Evaluation of partial-response maximum-likelihood detection for phase-change optical data storage“. Applied Optics 38, Nr. 20 (10.07.1999): 4394. http://dx.doi.org/10.1364/ao.38.004394.

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Kumar, M. S. Vijaya, Kazuhiko Kuribayashi und Koichi Kitazono. „Formation of LuFe2O4 phase from an undercooled LuFeO3 melt in reduced oxygen partial pressure“. Journal of Materials Research 23, Nr. 11 (November 2008): 2996–3005. http://dx.doi.org/10.1557/jmr.2008.0359.

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The formation of metastable phases from an undercooled LuFeO3 melt was investigated under reduced Po2 since the iron ion has the tendency to change its valence state from Fe3+ to Fe2+ in an ambient atmosphere with low Po2. The nucleation and the post-recalescence temperatures of the phases were decreased with decreasing process Po2. Phase equilibrium was established in the Lu–Fe–O system at 1473 K by varying the oxygen partial pressure from 105 to 10−1 Pa. A possible ternary metastable phase diagram depending on the oxygen composition in the bulk sample was also constructed. The formation of the LuFe2O4 phase where the Fe3+ and Fe2+ ratio is 1:1 clearly indicated that the formation of metastable phases is related to the presence of Fe2+ ions. Thermogravimetric analysis revealed that the increase in sample mass with decreasing process Po2, down to 10−1 Pa, is relatively dependent on the amount of Fe2+ ions.

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Perlis, Michael, Knashawn Morales, Ivan Vargas, Alexandria Muench, Mark Seewald, Breanna D’Antonio und Michael Grandner. „368 Durability of Tx Response to Zolpidem using a Partial Reinforcement Regimen: Does this strategy require contingent reinforcement?“ Sleep 44, Supplement_2 (01.05.2021): A146—A147. http://dx.doi.org/10.1093/sleep/zsab072.367.

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Abstract Introduction In 2015, partial reinforcement (PR) was assessed as an alternative approach to maintenance therapy with zolpidem. The method being: once a treatment response is obtained over the course of 1-month’s Tx with QHS dosing (Phase-1), Tx response can maintained over time with a PR regimen (Phase-2 [nightly pill/capsule use with 50% of capsules having medication and 50% having only inert filler]). In that study, it was assumed that Phase1 QHS dosing was required 1) to maximize treatment responding and 2) for the conditioning of pharmacologic responses to the medication vehicle (capsule). In the present study, these assumptions were tested by including both QHS and PR arms into Phase-1. Methods In Phase-1 (1 month), subjects were randomized to the QHS or PRS conditions (2QHS:1PRS). In Phase-2 (3 months), the PRS group continued forward without a change in the treatment regimen (variable dose [VD-VD]) and the QHS group was re-randomized to either continued QHS Tx (full dose [FD-FD]) or to PRS Tx [FD-VD]). Both study phases were evaluated for treatment responses rates and for average change in TWT (SL+WASO+EMA). Results 55 subjects (age 61.2+/-8.1, 64% female, & 73% white) were enrolled into Phase-1; 39 were randomized to the QHS condition and 16 to the PRS condition. In Phase-1, 77% (QHS) and 50% (PRS) exhibited treatment responses (p=0.09) where the average change in TWT was similar by group (QHS was -43min [CI -76,-9] and PRS was -76min [CI -138,-14];p=0.35). In Phase-2, 73% (FD-FD), 57% (FD-VD), and 88% (VD-VD) exhibited continued treatment responses (p=0.22) where the average improvement of TWT continued with FD-FD and remained stable for FD-VD and VD-VD (p<0.01). Conclusion These data, while preliminary, suggest that QHS (vs. PRS) dosing produces more treatment responders and similar initial effects on sleep continuity during Phase-1, comparable maintenance of treatment response over time, and continued improvement on sleep continuity during Phase-2. These results suggest that partial reinforcement can maintain effects but cannot allow for the additional clinical gains afforded by continuous treatment. Given this, it may be the case that the partial reinforcement technique could be improved upon by extending phase from 1 to 2–4 months. Support (if any):

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Ivanova, A. A. „Calculation of Phase-Change Boundary Position in Continuous Casting“. Archives of Foundry Engineering 13, Nr. 4 (01.12.2013): 57–62. http://dx.doi.org/10.2478/afe-2013-0082.

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Abstract The problem of determination of the phase-change boundary position at the mathematical modeling of continuous ingot temperature field is considered. The description of the heat transfer process takes into account the dependence of the thermal physical characteristics on the temperature, so that the mathematical model is based on the nonlinear partial differential equations. The boundary position between liquid and solid phase is given by the temperatures equality condition and the Stefan condition for the two-dimensional case. The new method of calculation of the phase-change boundary position is proposed. This method based on the finite-differences with using explicit schemes and on the iteration method of solving of non-linear system equations. The proposed method of calculation is many times faster than the real time. So that it amenable to be used for model predictive control of continuous semifinished product solidification.

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Kamkari, Babak, und Hossein Shokouhmand. „Experimental investigation of phase change material melting in rectangular enclosures with horizontal partial fins“. International Journal of Heat and Mass Transfer 78 (November 2014): 839–51. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2014.07.056.

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Li, Hongjun, C. K. Hsieh und D. Y. Goswami. „Source and Sink Method of Solution of Two-Dimensional Phase Change for Energy Storage“. Journal of Solar Energy Engineering 116, Nr. 2 (01.05.1994): 100–106. http://dx.doi.org/10.1115/1.2930496.

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A source and sink method has been developed for the solution of heat transfer with phase change in two dimensions. In this method, the heat transfer in one direction is decoupled from that in the other direction by changing the second partial differential in the direction where the phase change is less dominant to a finite difference form and solving the problem in the other direction with an analytical solution that accounts for the motion of the interface in a phase-change problem. The solution developed in this paper is thus independent of the equations used to represent the interface as well as the conditions imposed on the boundaries. In the present paper, the method has been applied to the tracking of a single melting front formed by different phases assuming equal properties. The method has been demonstrated to be accurate, convergent, and stable by numerical computations as well as experimental measurements. Extension of the method to more general problems has also been discussed.

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Niwa, Eiki, Tsubasa Sato und Takuya Hashimoto. „Thermodynamic analyses of the orthorhombic-to-tetragonal phase transition in Pr2−xNdxNiO4+δ under controlled oxygen partial pressures“. Dalton Transactions 49, Nr. 34 (2020): 11931–41. http://dx.doi.org/10.1039/d0dt02119a.

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The standard entropy change, ΔS°, and enthalpy change, ΔH°, at the structural phase transition of Pr_2−xNd_xNiO_4+δ and their impact on variation of phase transition temperature by Nd content.

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Hsino, Mahmoud, und Jerzy Pasławski. „Phase Change Materials as a Modifier of Ageing Cement Concrete in Hot and Dry Climate“. Advanced Materials Research 804 (September 2013): 129–34. http://dx.doi.org/10.4028/www.scientific.net/amr.804.129.

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This paper is devoted to the use of Phase Change Materials as a cement concrete modifier in Middle East climate. Due to large amplitude of daily air temperature in these conditions, Phase Change Materials can be used to reduce the dynamic of thermal peak in an ageing concrete. Partial results of studies to determine the influence of various factors on the effects of modifications are presented

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Sega, Marcello, und György Hantal. „Phase and interface determination in computer simulations of liquid mixtures with high partial miscibility“. Physical Chemistry Chemical Physics 19, Nr. 29 (2017): 18968–74. http://dx.doi.org/10.1039/c7cp02918g.

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Partially miscible solutions can represent a challenge from the computer simulation standpoint, especially if the mutual solubility of the components is so large that their concentrations do not change much from one phase to another. A density-based clustering approach with quasi-linear scaling is shown to provide consistent phase identification.

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BERMÚDEZ, A., R. MUÑOZ-SOLA und F. PENA. „A nonlinear partial differential system arising in thermoelectricity“. European Journal of Applied Mathematics 16, Nr. 6 (14.07.2005): 683–712. http://dx.doi.org/10.1017/s0956792505006212.

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In this paper we prove the existence of a solution for a system of nonlinear parabolic partial differential equations arising from thermoelectric modelling of metallurgical electrodes undergoing a phase change. The model consists of an electromagnetic problem for eddy current computation coupled with a Stefan problem for temperature. The proof uses a regularized problem obtained by truncating the source term in temperature equation. Passing to the limit requires fine a priori estimates leading to compactness.

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Nakamura, Atsushi, Mamoru Shoji, Harumitsu Miyashita, Naoyasu Miyagawa, Noboru Yamada und Takashi Ishida. „High-Density Recording on a Dual-Layer Phase Change Disk Using Partial Response Maximum Likelihood Method“. Japanese Journal of Applied Physics 42, Part 1, No. 2B (28.02.2003): 1072–73. http://dx.doi.org/10.1143/jjap.42.1072.

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Go, Shao Xiang, Tae Hoon Lee, Stephen R. Elliott, Natasa Bajalovic und Desmond K. Loke. „A fast, low-energy multi-state phase-change artificial synapse based on uniform partial-state transitions“. APL Materials 9, Nr. 9 (01.09.2021): 091103. http://dx.doi.org/10.1063/5.0056656.

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Wu, Wei, Fan Jia, Richard Kinai und Todd D. Little. „Optimal number and allocation of data collection points for linear spline growth curve modeling“. International Journal of Behavioral Development 41, Nr. 4 (24.04.2016): 550–58. http://dx.doi.org/10.1177/0165025416644076.

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Spline growth modelling is a popular tool to model change processes with distinct phases and change points in longitudinal studies. Focusing on linear spline growth models with two phases and a fixed change point (the transition point from one phase to the other), we detail how to find optimal data collection designs that maximize the efficiency of detecting key parameters in the spline models, holding the total number of data points or sample size constant. We identify efficient designs for the cases where (a) the exact location of the change point is known (complete certainty), (b) only the interval that contains the change point is known (partial certainty), and (c) no prior knowledge on the location of the change point is available (zero certainty). We conclude with recommendations for optimal number and allocation of data collection points.

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Mehryan, S. A. M., Kaamran Raahemifar, Leila Sasani Gargari, Ahmad Hajjar, Mohamad El Kadri, Obai Younis und Mohammad Ghalambaz. „Latent Heat Phase Change Heat Transfer of a Nanoliquid with Nano–Encapsulated Phase Change Materials in a Wavy-Wall Enclosure with an Active Rotating Cylinder“. Sustainability 13, Nr. 5 (01.03.2021): 2590. http://dx.doi.org/10.3390/su13052590.

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A Nano-Encapsulated Phase-Change Material (NEPCM) suspension is made of nanoparticles containing a Phase Change Material in their core and dispersed in a fluid. These particles can contribute to thermal energy storage and heat transfer by their latent heat of phase change as moving with the host fluid. Thus, such novel nanoliquids are promising for applications in waste heat recovery and thermal energy storage systems. In the present research, the mixed convection of NEPCM suspensions was addressed in a wavy wall cavity containing a rotating solid cylinder. As the nanoparticles move with the liquid, they undergo a phase change and transfer the latent heat. The phase change of nanoparticles was considered as temperature-dependent heat capacity. The governing equations of mass, momentum, and energy conservation were presented as partial differential equations. Then, the governing equations were converted to a non-dimensional form to generalize the solution, and solved by the finite element method. The influence of control parameters such as volume concentration of nanoparticles, fusion temperature of nanoparticles, Stefan number, wall undulations number, and as well as the cylinder size, angular rotation, and thermal conductivities was addressed on the heat transfer in the enclosure. The wall undulation number induces a remarkable change in the Nusselt number. There are optimum fusion temperatures for nanoparticles, which could maximize the heat transfer rate. The increase of the latent heat of nanoparticles (a decline of Stefan number) boosts the heat transfer advantage of employing the phase change particles.

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Bondareva, Nadezhda S., und Mikhail A. Sheremet. „Numerical Simulation of Melting of Phase Change Material in a Square Cavity with a Heat Source“. Key Engineering Materials 685 (Februar 2016): 104–8. http://dx.doi.org/10.4028/www.scientific.net/kem.685.104.

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Melting and solidification problems are important in applications of many industries. In the present work mathematical simulation of natural convection with phase transition inside an enclosure with a local heat source has been carried out. Partial differential equations with corresponding initial and boundary conditions have been solved using the finite difference method. The effect of temperature differences on fluid flow and heat transfer has been discussed.

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Maffoni, Silvia, Silvia Brazzo, Rachele De Giuseppe, Ginevra Biino, Ilaria Vietti, Cristina Pallavicini und Hellas Cena. „Lifestyle Changes and Body Mass Index during COVID-19 Pandemic Lockdown: An Italian Online-Survey“. Nutrients 13, Nr. 4 (29.03.2021): 1117. http://dx.doi.org/10.3390/nu13041117.

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Background. COVID-19 pandemic has imposed a period of contingency measures, including total or partial lockdowns all over the world leading to several changes in lifestyle/eating behaviours. This retrospective cohort study aimed at investigating Italian adult population lifestyle changes during COVID-19 pandemic “Phase 1” lockdown (8 March–4 May 2020) and discriminate between positive and negative changes and BMI (body mass index) variations (ΔBMI). Methods. A multiple-choice web-form survey was used to collect retrospective data regarding lifestyle/eating behaviours during “Phase 1” in the Italian adult population. According to changes in lifestyle/eating behaviours, the sample was divided into three classes of changes: “negative change”, “no change”, “positive change”. For each class, correlations with ΔBMI were investigated. Results. Data were collected from 1304 subjects (973F/331M). Mean ΔBMI differed significantly (p < 0.001) between classes, and was significantly related to water intake, alcohol consumption, physical activity, frequency of “craving or snacking between meals”, dessert/sweets consumption at lunch. Conclusions. During “Phase 1”, many people faced several negative changes in lifestyle/eating behaviours with potential negative impact on health. These findings highlight that pandemic exacerbates nutritional issues and most efforts need to be done to provide nutrition counselling and public health services to support general population needs.

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Guo, Y. C., H. K. Liu und S. X. Dou. „Phase evolution in silver-doped BiPbSrCaCuO(2223)/Ag superconducting composites“. Journal of Materials Research 8, Nr. 9 (September 1993): 2187–90. http://dx.doi.org/10.1557/jmr.1993.2187.

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Silver doping into (Bi, Pb)2Sr2Ca2Cu3O10 superconducting composite tapes was found to accelerate the formation process of high-Tc (2223) phase owing to lowering the partial melting point of the samples. The differential thermal analysis (DTA) results showed that the partial melting temperature of the sample was lowered by about 10 °C from 850 °C to 840 °C by silver doping. However, with sufficient sintering both the silver-doped and undoped samples can reach a very high level of high-Tc phase fraction, suggesting that the silver doping only speeds up the rate of high-Tc phase formation, but does not change the final phase assemblage of the materials. The reaction kinetics was analyzed by using the Avrami equation, and the results indicated that the conversion process of low-Tc (2212) phase to high-Tc (2223) phase was a diffusion-controlled, two-dimensional reaction. The correlation of the phase evolution with electrical property inside the superconducting tape during the process of heat treatment was also discussed.

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Bell, A. M. T., R. A. D. Pattrick und D. J. Vaughan. „Structural evolution of aqueous mercury sulphide precipitates: energy-dispersive X-ray diffraction studies“. Mineralogical Magazine 74, Nr. 1 (Februar 2010): 85–96. http://dx.doi.org/10.1180/minmag.2010.074.1.85.

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AbstractIn situ, high-temperature energy-dispersive X-ray powder diffraction (EDXRD) data have been collected on synthetic and a natural sample of mercury sulphide (HgS). These measurements were made between temperatures of 295 and 798 K. Synthetic samples of HgS were prepared by reaction between sulphide and mercury in aqueous solution. In a subsequently dried and aged synthetic HgS sample, heated in vacuo, there is a change from a poorly crystalline pseudocubic material into a well crystalline cubic material in the temperature region 583–623 K. At higher temperature (748 K), there is evidence for a partial phase transition to the high temperature hypercinnabar HgS structure. In a neoformed synthetic sample, heated in a sealed Ti container, the initial ‘pseudocubic’ metacinnabar phase partially transforms to a previously unknown phase (XHgS) in the temperature range 467–522 K. This phase disappears at 527 K, and the metacinnabar phase changes to a well crystalline cubic phase; cinnabar develops at 542 K. The proportion of cinnabar continues to increase up to 647 K. Both metacinnabar and cinnabar phases are retained on cooling. No phase transitions were observed for the natural cinnabar sample.

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Rakotondrandisa, Aina, Ionut Danaila und Luminita Danaila. „Numerical modelling of a melting-solidification cycle of a phase-change material with complete or partial melting“. International Journal of Heat and Fluid Flow 76 (April 2019): 57–71. http://dx.doi.org/10.1016/j.ijheatfluidflow.2018.11.004.

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Mendis, Shanthi, U. Samarajeewa und R. O. Thattil. „Coconut fat and serum lipoproteins: effects of partial replacement with unsaturated fats“. British Journal of Nutrition 85, Nr. 5 (Mai 2001): 583–89. http://dx.doi.org/10.1079/bjn2001331.

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The aim of the present study was to examine the effect of reducing saturated fat in the diet, or partly replacing it with unsaturated fat, on the serum lipoprotein profile of human subjects. The study had two intervention periods, 8 weeks (phase 1) and 52 weeks (phase 2). In phase 1, total fat was reduced from 31 to 25 % energy (polyunsaturated fatty acids (PUFA):saturated fatty acids (SFA) ratio increased from 0.2 to 0.4) by reducing the quantity of coconut fat (CF) in the diet from 17.8 to 9.3 % energy intake. In phase 2, subjects were randomised to groups A and B. In group A total fat was reduced from 25 to 20 % energy (PUFA:SFA ratio increased from 0.4 to 0.7) by reducing the quantity of CF in the diet from 9.3 to 4.7 % total energy intake. In group B, the saturated fat content in the diet was similar to group A. In addition a test fat (a mixture of soyabean oil and sesame oil, PUFA:monosaturated fatty acids ratio 2) contributed 3.3 % total energy intake and total fat contributed 24 % energy intake (PUFA:SFA ratio increased from 0.7 to 1.1). At the end of phase 1, there was a 7.7 % reduction in cholesterol (95 % CI -3.6, -12.2) and 10.8 % reduction in LDL (95 % CI -4.9, -16.5) and no significant change in HDL and triacylglycerol. At the end of phase 2, the reduction in cholesterol in both groups was only about 4 % (95 % CI -12, 3.2) partly due the concomitant rise in HDL. The reduction in LDL at 52 weeks was significantly higher in group B (group A mean reduction 11 %, 95 % CI -20.1, -2.0 and group B mean reduction 16.2 % 95 % CI -23.5, -8.9). In phase 2, triacylglycerol levels showed a mean reduction of 6.5 % in group 2A and a mean increase of 8.2 % in group 2B. The reduction of saturated fat in the diet is associated with a lipoprotein profile that would be expected to reduce cardiovascular risk. The reduction of dietary saturated fat with partial replacement of unsaturated fat brings about changes in total cholesterol, HDL- and LDL-cholesterol that are associated with a lower cardiovascular risk.

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Davis, Ronald, Charlotte Sanborn, David Nichols, David M. Bazett-Jones und Eric L. Dugan. „The Effects of Whole Body Vibration on Bone Mineral Density for a Person With a Spinal Cord Injury: A Case Study“. Adapted Physical Activity Quarterly 27, Nr. 1 (Januar 2010): 60–72. http://dx.doi.org/10.1123/apaq.27.1.60.

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Bone mineral density (BMD) loss is a medical concern for individuals with spinal cord injury (SCI). Concerns related to osteoporosis have lead researchers to use various interventions to address BMD loss within this population. Whole body vibration (WBV) has been reported to improve BMD for postmenopausal women and suggested for SCI. The purpose of this case study was to identify the effects of WBV on BMD for an individual with SCI. There were three progressive phases (standing only, partial standing, and combined stand with vibration), each lasting 10 weeks. Using the least significant change calculation, significant positive changes in BMD were reported at the trunk (0.46 g/cm2) and spine (.093 g/cm2) for phase 3 only. Increases in leg lean tissue mass and reduction in total body fat were noted in all three phases.

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Vera-Puerto, Ismael, Hugo Valdés, Christian Correa, Valeria Perez, Roberto Gomez, Erica Alarcon und Carlos Arias. „Evaluation of Bed Depth Reduction, Media Change, and Partial Saturation as Combined Strategies to Modify in Vertical Treatment Wetlands“. International Journal of Environmental Research and Public Health 18, Nr. 9 (01.05.2021): 4842. http://dx.doi.org/10.3390/ijerph18094842.

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The aim of this work was to evaluate the performance of vertical subsurface flow treatment wetlands (VSSF TWs) for treating rural domestic wastewater when strategies such as bed depth reduction and media change are used in combination with bottom saturation. Two treatment wetland systems were implemented: normal (VF-N), with a bed depth of 1.0 m, and modified (VF-M), with a bed depth of 0.5 m and a bottom layer of natural zeolite. Schoenoplectus californicus was used as experimental plant. These two treatment systems were operated at a hydraulic loading rate of 120 mm/d in two phases. Phase I did not use bottom saturation, while Phase II involved a bottom saturation of the zeolite layer of the VF-M system. The results show that bed depth reduction did not have a significant effect (p > 0.05) in terms of organic matter, solids, and ammonium removal. Conversely, it had a significant influence (p < 0.05) on phosphate as well as a negative effect on pathogen removal. This influence could be explained by initial media capacity for phosphorus removal and filtration importance in the case of pathogens. Partial saturation only had a positive influence on total nitrogen removal. The addition of a bottom layer of natural zeolite showed no positive effect on nutrient removal. The plant showed adaptation and positive development in both VF-N and VF-M. The water balance showed that water loss was not influenced by bed depth reduction. Therefore, according to the previous results, a combination of the proposal modifications to VSSF TWs can be introduced for treating rural domestic wastewater.

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Takekiyo, Takahiro, Yusuke Imai, Hiroshi Abe und Yukihiro Yoshimura. „Conformational Analysis of Quaternary Ammonium-Type Ionic Liquid Cation, N,N-Diethyl-N-methyl-N-(2-methoxyethyl) Ammonium Cation“. Advances in Physical Chemistry 2012 (23.08.2012): 1–7. http://dx.doi.org/10.1155/2012/829523.

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Conformational preference of N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium cation ([DEME]+), which is one of the quaternary ammonium-based ionic liquid cation, in the gas phase has been investigated using a density functional theory (DFT) calculation. Eight candidates for the stable conformers of [DEME]+ exist in the gas phase, and can it energetically classify into two groups. One is a five conformers group, which has the intramolecular attractive interaction form (the folded form). The other is a three conformers group, which is the noninteraction form (the extended form). The transformation from the folded form to the extended form induces large changes in the dipole moment and partial charges of N and O atoms. Here we show that the difference in the dipole moment and partial charges of N and O atoms associated with the conformational change of [DEME]+ are closely related to the molecular orientation of [DEME]-based ionic liquids in the liquid state.

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Mihai, Dana Nicoleta, Dan Mihailescu, Sorin Alexandru Ibanescu, Liliana Savin, Victor Grigorescu, Alexandru Patrascu und Marcel Ionel Popa. „Polymeric Biomaterials with Complementary Role in the Articular Endoprosthesis I. Surface Characteristics“. Materiale Plastice 56, Nr. 2 (30.06.2019): 306–8. http://dx.doi.org/10.37358/mp.19.2.5176.

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The change of the organic bone cements�composition (COO) determines the adjustment of some important properties for the behaviour as fixing material, such as the: superficial tension, polarity, surface energy, viscosity, contraction at polymerisation, porosity. In the present paper we monitored the influence of the composition�s changes for some acrylic cements upon their handling features. The samples were obtained via the partial replacement of the methyl methacrylate (MMA) in the liquid phase of some usual formulas with another acrylic monomer. For these, it was measured the contact angles as wettablility of the fixing material. Moreover, it was estimated the values of the hardening time, important parameter for the application phases of the cements with cold hardening and fixing of the articular endoprostheses.

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WONG, JENNY Y. Y., und ZUO-GUANG YE. „SYNTHESIS AND PHASE ANALYSIS OF A NEW FERROELECTRIC (K0.5Na0.5)NbO3–Bi0.5K0.5TiO3–BaTiO3 TERNARY SOLID SOLUTION“. Journal of Advanced Dielectrics 01, Nr. 02 (April 2011): 243–49. http://dx.doi.org/10.1142/s2010135x11000288.

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In order to develop new lead-free pieozoelectric/ferroelectric materials, the y( K0.5Na0.5 ) NbO3 – (1 - y)[(1 - x) Bi0.5K0.5TiO3 – x BaTiO3 ] solid solution system is synthesized and the partial ternary phase diagram in the KNN-rich region with compositions of y = 0.98 to y = 0.96 is established. All the compositions studied show a gradual phase change from a tetragonal to an orthorhombic structure as the BT component increases. A mixture of tetragonal and orthorhombic phases is found in the composition range of x = 0.25 to 0.60 and y = 0.97, and x = 0.50 to 0.75 and y = 0.96, indicating a ternary morphotropic phase boundary region. The piezoelectric and ferroelectric properties of the 0.97(KNN)–0.03[0.60BKT–0.40BT] ceramics are characterized. The increase in remnant polarization as compared with pure KNN shows improved ferroelectricity by forming the ternary solid solution.

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Li, Xia, Ting Zhong, Rong Tang, Chao Wu, Yuting Xie, Fang Liu und Zhiguang Zhou. „PD-1 and PD-L1 Expression in Peripheral CD4/CD8+ T Cells Is Restored in the Partial Remission Phase in Type 1 Diabetes“. Journal of Clinical Endocrinology & Metabolism 105, Nr. 6 (01.04.2020): 1947–56. http://dx.doi.org/10.1210/clinem/dgaa130.

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Abstract Context Partial remission (PR) in type 1 diabetes (T1D) is accompanied by downregulation of the immune response. Programmed cell death-1 (PD-1) and its ligand (PD-L1) are important immunosuppressive molecules, but their changes in the PR phase are unclear. Objective We investigated the dynamic changes of PD-1/PD-L1 expression on T cells around the PR phase in T1D. Methods Ninety-eight T1D patients were recruited cross-sectionally and grouped according to PR status into nonremitters (individuals who did not undergo PR during the disease course; n = 39), pre-PR (n = 15), mid-PR (n = 30), and post-PR (n = 14) subgroups. PR was defined according to C-peptide level ≥300 pmol/L or index of insulin-adjusted hemoglobin A1c ≤9 as recommended. Among all the 98 patients, 29 newly diagnosed individuals were prospectively followed up for 1 year. The dynamic changes of PD-1/PD-L1 expression, frequency of regulatory T cells (Tregs) and IL-35+ Tregs among peripheral CD4/CD8+ T cells were determined. Results PD-1/PD-L1 on CD4+/CD8+ T cells showed a dynamic change around the PR phase: lowest in pre-PR phase, restored in mid-PR phase, and declined again in post-PR phase. Conversely, this pattern did not occur for nonremitters. Notably, PD-1 expression on CD8+ T cells in mid-PR was positively correlated with the length of the PR phase. The percentages of circulating Tregs and IL-35+ Tregs showed no relation to PR. Conclusions The PR phase is associated with restoration of PD-1/PD-L1 on CD4+ and CD8+ T cells, suggesting that PD-1/PD-L1 may be a potential target for prolonging this phase in T1D.

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Robinson, Bruce, Martin Schlumberger, Lori J. Wirth, Corina E. Dutcus, James Song, Matthew H. Taylor, Sung-Bae Kim et al. „Characterization of Tumor Size Changes Over Time From the Phase 3 Study of Lenvatinib in Thyroid Cancer“. Journal of Clinical Endocrinology & Metabolism 101, Nr. 11 (17.10.2016): 4103–9. http://dx.doi.org/10.1210/jc.2015-3989.

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Context: Lenvatinib improved the progression-free survival (PFS) and overall response rate of patients with radioiodine-refractory differentiated thyroid cancer vs placebo in the Phase 3 Study of (E7080) Lenvatinib in Differentiated Cancer of the Thyroid (SELECT). Objective: The objective of the study was to characterize tumor size changes with lenvatinib treatment. Design: SELECT was a phase 3, randomized, double-blind, multicenter study. Setting: In this clinical trial, tumor assessments of lenvatinib (n = 261) and placebo-treated (n = 131) patients were performed by independent radiological review per Response Evaluation Criteria in Solid Tumors version, 1.1 at 8-week intervals. Patients: Patients with complete or partial response were defined as responders to lenvatinib (n = 169). Of the 92 nonresponders, 76 had at least one postbaseline tumor assessment and were included in this analysis. Interventions: Lenvatinib (24 mg once daily) or placebo in 28-day cycles until unacceptable toxicity, disease progression, or death. Main Outcome Measures: This was an exploratory analysis of key end points from SELECT, including PFS, overall response rate, and tumor reduction. Results: The median maximum percentage change in tumor size was −42.9% for patients receiving lenvatinib (responders, −51.9%; nonresponders, −20.2%). Tumor size reduction was most pronounced at first assessment (median, −24.7% at 8 wk after randomization); thereafter, the rate of change was slower but continuous (−1.3% per mo). In a multivariate model, percentage change in tumor size at the first assessment was a marginally significant positive predictor for PFS (P = .06). Conclusions: The change in tumor size conferred by lenvatinib was characterized by two phases: an initial, rapid decline, followed by slower, continuous shrinkage.

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Morozov, L. N., Yu L. Pavlov, E. S. Timoshin und O. Yu Alekperov. „OXIDIZING REACTIVATION OF COPPER CATALYST FOR METHANOL SYNTHESIS“. IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, Nr. 1 (07.06.2018): 42. http://dx.doi.org/10.6060/tcct.20165901.5263.

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The change in phase composition and catalytic properties of a copper-containing catalyst for methanol synthesis which was deactivated under industrial operation was studied at its redox treatment. The possibility of catalyst partial reactivation was shown. Conditions of reactivation were choosen at the increase in catalyst running time.

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Liu, Libin, und Zhanpeng Jin. „An investigation of the invariant reactions in the BiPbSrCaCuO system“. Journal of Materials Research 11, Nr. 9 (September 1996): 2142–51. http://dx.doi.org/10.1557/jmr.1996.0273.

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The phases present around the (Bi, Pb)2Sr2Ca2Cu3Ox (2223) phase between 830–880 °C have been studied by x-ray diffraction (XRD) and electron probe microanalysis (EPMA) methods. The decomposition and melting temperatures of the 2223 phase in these samples have been measured by the differential thermal analysis (DTA) method. Partial substitution of Bi with Pb (Pb: Bi = 3: 22) does not change the 850 °C phase relations around 2223 phase. 2223 decomposes to liquid, Sr7Ca7Cu24O41 (7724), and Ca2CuO3 at 875 °C. The invariant reactions (degree of freedom is zero) among 2223, 7724, Ca2CuO3, CuO, Bi2Sr2CaCu2O8 (2212), and liquid were proposed to be L + 7724 + Ca2CuO3 → 2223 + 2212, L + 7724 + Ca2CuO3 → 2223 + CuO, L + 7724 → 2223 + 2212 + CuO. The reaction temperatures were estimated to be 860 °C, 860 °C, and 854 °C, respectively. An invariant reaction scheme and a tentative liquidus projection were sketched out.

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Nomura, Katsumi, Saburo Hoshi, Yuichi Nakamura, Teruo Izumi und Yuh Shiohara. „Initial growth mechanism of Yba2Cu3Oycrystal on MgO substrate by liquid-phase epitaxy“. Journal of Materials Research 16, Nr. 10 (Oktober 2001): 2947–58. http://dx.doi.org/10.1557/jmr.2001.0405.

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Initial growth features of Yba2Cu3Oy (YBCO) crystal on an MgO substrate by a liquid-phase epitaxy (LPE) process were investigated and compared with homoepitaxial growth on a YBCO substrate. The partial dissolution of the seed grains in the initial stage of the LPE growth was influenced by the crystallinity of in-plane alignment of the seed grains, which could be explained by the preferential dissolution and growth mechanism. Concurrently, the slope angle of the growth grain varied with growth time. The opposite tendency of the slope angle change between the hetero- and the homoepitaxial growth was observed and could be explained by considering the difference in the step-advancing rates on each interface. It could be understood that the formation of entrapped liquid inclusions was the combination phenomena of both the small step-advancing rate of YBCO crystal on the MgO surface and the roughening of the MgO surface due to the partial dissolution of MgO to the solution.

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Kania, Romain E., Philippe Herman, Patrice Tran Ba Huy und Amos Ar. „Role of nitrogen in transmucosal gas exchange rate in the rat middle ear“. Journal of Applied Physiology 101, Nr. 5 (November 2006): 1281–87. http://dx.doi.org/10.1152/japplphysiol.00113.2006.

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This study investigates the role of nitrogen (N2) in transmucosal gas exchange of the middle ear (ME). We used an experimental rat model to measure gas volume variations in the ME cavity at constant pressure. We disturbed the steady-state gas composition with either air or N2 to measure resulting changes in volume at ambient pressure. Changes in gas volume over time could be characterized by three phases: a primary transient increase with time (phase I), followed by a linear decrease (phase II), and then a gradual decrease (phase III). The mean slope of phase II was −0.128 μl/min (SD 0.023) in the air group ( n = 10) and −0.105 μl/min (SD 0.032) in the N2 group ( n = 10), but the difference was not significant ( P = 0.13), which suggests that the rate of gas loss can be attributed mainly to the same steady-state partial pressure gradient of N2 reached in this phase. Furthermore, a mathematical model was developed analyzing the transmucosal N2 exchange in phase II. The model takes gas diffusion into account, predicting that, in the absence of change in mucosal blood flow rate, gas volume in the ME should show a linear decrease with time after steady-state conditions and gas composition are established. In accordance with the experimental results, the mathematical model also suggested that transmucosal gas absorption of the rat ME during steady-state conditions is governed mainly by diffusive N2 exchange between the ME gas and its mucosal blood circulation.

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Pereira, Veridiana Rotondaro, Antonio Cesar Amaru Maximiano und Diógenes de Souza Bido. „Resistance to change in BPM implementation“. Business Process Management Journal 25, Nr. 7 (14.10.2019): 1564–86. http://dx.doi.org/10.1108/bpmj-07-2018-0184.

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Purpose The purpose of this paper is to investigate individuals’ attitudes toward organizational change, considering each phase of a business process management (BPM) implementation and some antecedents of resistance as hierarchical position, sector and trust in management. Design/methodology/approach The study examines employees’ attitudes toward BPM change in the Brazilian market. To measure resistance to organizational change, the research adopted the change attitude scale developed by Oreg (2006). As potential antecedents for resistance, hierarchical position, sector and trust in management were considered. Five control variables were included: gender, company size, educational background, educational level and age range. The application of the survey considered three main parties: BPM implementers, BPM end-users and developers of BPM systems. The survey data, drawn from 113 useable questionnaires, were analyzed by structural equation modeling with partial least squares estimation. Findings The results of this research showed some interesting insights. First, hierarchical position has no significant effect on the reduction of resistance to process improvement changes. Contrary to what was expected, results showed that being in the manufacturing sector has no significant effect on the reduction of resistance. Finally, only trust in management has a significant effect on employees’ attitudes toward BPM implementation, and as phases go by this effect increases. Practical implications The paper could support BPM decision makers by providing a better understanding of employees’ attitudes toward BPM change. In this sense, the study could also provide real-life application, by facilitating the task of allocating priorities and supporting process-related decisions. Originality/value The research could incentivize a closer relationship between BPM implementers and BPM end-users, promoting opportunities, respect and mutual trust.

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Park, Cheol-Soo, und Yong-Soo Han. „A Study on the Change of Signal Intensity of Partial Fourier Phase Encoding and Average by Gd Contrast Concentration“. Korean Society of Medicine & Therapy Science 11, Nr. 2 (31.12.2019): 21–27. http://dx.doi.org/10.31321/kmts.2019.11.2.21.

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Liao, Q., und T. S. Zhao. „A visual study of phase-change heat transfer in a two-dimensional porous structure with a partial heating boundary“. International Journal of Heat and Mass Transfer 43, Nr. 7 (April 2000): 1089–102. http://dx.doi.org/10.1016/s0017-9310(99)00212-4.

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Lee, Hyukjae, und Shankar Mall. „Investigation into Tangential Force and Axial Stress Effects on Fretting Fatigue Behavior“. Journal of Engineering Materials and Technology 128, Nr. 2 (15.06.2005): 202–9. http://dx.doi.org/10.1115/1.2172624.

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Fretting fatigue behavior of a titanium alloy was investigated using a dual actuator test setup which was capable to apply the pad displacement independent of the applied cyclic load on specimen. Fretting fatigue tests were conducted using this setup with a phase difference between cyclic load on the specimen and tangential force on the fretting pad with cylinder-on-flat contact configuration under partial slip condition. Two axial stress ratios were used. The relative slip range and tangential force range were related to each other and this relationship was not influenced by phase difference, axial stress ratio, and contact load under the partial slip condition. Change in the phase difference caused the change in relative slip as well as tangential force for a given applied pad displacement and axial load. However, there was no effect of phase difference on fretting fatigue life at a given relative slip level. Fretting fatigue tests with a fully reversed axial stress showed longer fatigue life than tension-tension counterparts at a given relative slip, tangential force range, and axial stress range. Finite element analysis was conducted by including the complete load history effects, which showed that stress distribution on the contact surface stabilized after the first fatigue cycle. Unlike relative slip and∕or tangential force range, a critical plane-based parameter appears to take into account the stress ratio effects to characterize fretting fatigue behavior.

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Asadi, Mehdi, Nicole Schulze und Heinz Palkowski. „Use of the Aging Effect to Change the Local Properties of Structure Components“. Advanced Materials Research 137 (Oktober 2010): 35–79. http://dx.doi.org/10.4028/www.scientific.net/amr.137.35.

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This research deals with processes leading to local strengthening effects in Advanced High Strength Steels (AHSS). Dual phase (DP), retained austenite (RA) - both hot and cold rolled - and complex phase (CP) steels have been investigated to examine the effect of thermal and mechanical processing parameters on local properties. For this purpose, a method has been investigated to achieve local strengthening, namely local deformation and local heat treatment. Samples were locally deformed by bending and embossing processes. A local deformation with defined pre-strains leads to enhanced hardness and strengthening. A subsequent aging treatment leads to a further increase in mechanical properties. Local heat treatment was applied using a laser and an electron beam. Following local heat treatment with selected parameters, the microstructure of the surface and the cross section as well as the mechanical properties were evaluated by light optical, scanning as well as transmission electron microscopy, hardness measurement, tensile testing and thermal modelling. It can be stated that with partial heat treatment, local high strengthening can be produced. At lower heat treating temperatures, this effect could be attributed to bake hardening. With increased heat treating temperature, the initial microstructure near the surface is affected. A model can be improved, which defines the correlation between the influencing parameters and the local properties. The influence of over-aging in locally strengthen regions has been studied. For this investigation, parameters are stable to locally adjust the strengthening effect. Partial strengthening of AHSS by local deformation or local heat treatment can open up new fields of applications for locally using the strengthening effect to only influence relevant areas of interest, thus providing the potential for saving energy and designing the component’s behaviour.

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Cong, C. X., B. Yao, Y. P. Xie, G. Z. Xing, B. H. Li, X. H. Wang, Z. P. Wei et al. „Nitrogen partial pressure-dependent Mg concentration, structure, and optical properties of MgxZn1−xO film grown by magnetron sputtering“. Journal of Materials Research 22, Nr. 10 (Oktober 2007): 2936–42. http://dx.doi.org/10.1557/jmr.2007.0375.

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MgxZn1−xO films were grown on quartz substrates at 773 K by using radio frequency magnetron sputtering with a mixture of argon and nitrogen as sputtering gases. The nitrogen concentration in the mixture is characterized by the nitrogen partial pressure ratio, which is determined by the ratio of nitrogen flow rate to the flow rates of nitrogen and argon. It was found that Mg concentration, structure, and band gap of the MgxZn1−xO film could be tuned by changing the nitrogen partial pressure ratio of the sputtering gases. The Mg concentration in the MgxZn1−xO film increases with increasing nitrogen partial pressure ratio. The MgxZn1−xO film consists of wurtzite phase at the ratios from 0% to 50%, mixture of wurtzite and cubic phases at the ratios between 50% and 83%, and cubic phase at 100%. The band gap of the MgxZn1−xO film with wurtzite and cubic structure increases as the ratio rises. The variation of the structure and band gap is attributed to change of the Mg concentration, which results from loss of the O and Zn atoms during growth process, the former is induced by reaction between N and O, and the latter by re-evaporation of Zn atoms due to high substrate temperature. The mechanism of the loss of the O and Zn atoms is discussed based on thermodynamics.

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Rao, Dasari Kondala, Srinivas Kolla, C. Tara Sasanka und D. Sameer Kumar. „Study of Combined Effect of Inclination and Partial Fins on Melting of Phase Change Material in A Rectangular Enclosure Using CFD“. Journal of Modeling and Simulation of Materials 1, Nr. 1 (31.12.2018): 30–38. http://dx.doi.org/10.21467/jmsm.1.1.30-38.

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This study presents the combined effect of inclination and internal fins on the melting rate of PCM in a rectangular enclosure (8.89cm×6.35cm). The rectangular enclosure has a hot wall with a temperature of 311K, a cold wall with a temperature of 301.3K and the other two walls are insulated. Gallium with very low Prandtl number is taken as the PCM in this study. First, the individual effects of different inclinations (0⁰, 45⁰ and 90⁰) of the enclosure on melting rate of PCM are studied followed by the study of the effect of internal fins. Then we provide a combined environment of inclination and partial fins and obtain the results of liquid fraction, velocity contours and temperature distributions. Plots for the liquid fraction and average temperatures with respect to time are also obtained. Finally, the results and plots of the combined effect are compared with those of other conditions. From the comparison, we conclude that the combined effect of inclination and partial fins under constant normal gravity condition greatly enhances the heat transfer in PCM.

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Thorpe, H. C., S. C. Thomas und J. P. Caspersen. „Residual-tree growth responses to partial stand harvest in the black spruce (Picea mariana) boreal forestThis article is one of a selection of papers published in the Special Forum IUFRO 1.05 Uneven-Aged Silvicultural Research Group Conference on Natural Disturbance-Based Silviculture: Managing for Complexity.“ Canadian Journal of Forest Research 37, Nr. 9 (September 2007): 1563–71. http://dx.doi.org/10.1139/x07-148.

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Variants of partial harvesting are gaining favour as means to balance ecosystem management and timber production objectives on managed boreal forest landscapes. Understanding how residual trees respond to these alternative silvicultural treatments is a critical step towards evaluating their potential from either a conservation or a wood supply perspective. We used dendroecological techniques combined with a chronosequence approach to quantify the temporal radial growth response pattern of residual black spruce ( Picea mariana (Mill.) BSP) trees to partial harvest in northeastern Ontario. At its peak, 8–9 years after harvest, radial growth of residual trees had doubled. The growth pattern was characterized by a 2-year phase of no response, a subsequent period of increase 3–9 years after harvest, and a stage of declining rates 10–12 years after harvest. The magnitude of tree growth response depended strongly on tree age: peak postharvest growth was substantially higher for young trees, while old trees displayed only modest growth increases. Both the large magnitude and the time delay in postharvest growth responses have important implications for the development of more accurate quantitative tools to project future yields and, more generally, for determining whether partial harvesting is a viable management option for the boreal forest.

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