cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.17632/rhbj4xp288.2
title: the data of "Differences of the Neutrophil-Lymphocyte Ratios at 24 hours Postpartum Women Between two Delivery Modes and their Relationship to the Onset of Lactation: a Prospective Cohort Study"

description: Background: Delayed onset of lactation is a key factor for the low rate of exclusive breast-feeding during the 6 months after cesarean section. The mechanism of delayed onset of lactation is not clear. Milk production depends largely on mitochondria adenosine triphosphate (ATP) synthesis, and neutrophil-lymphocyte ratio is closely related to mitochondrial DNA copy number and ATP production. At present, it has not been explored whether a difference in neutrophil-lymphocyte ratio exists between the vaginal delivery group and the cesarean delivery group and, if so, whether the difference correlates to the time of onset of lactation. Objectives: To identify whether neutrophil-lymphocyte ratio at 24 hours after delivery is different between mothers in the cesarean section and the vaginal birth and whether the neutrophil-lymphocyte ratio is related to delayed onset of lactation. Design: The study adopted a prospective cohort study design. Settings: Maternity units of an Obstetrics & Gynecology Hospital. Methods: Mother-infant pairs were entered the vaginal birth group and the cesarean section group according to the way they gave birth. The neutrophil-lymphocyte ratio was calculated as the absolute value of neutrophils divided by the absolute value of lymphocytes based on full blood counts. Before delivery, the full blood counts were obtained from medical records. While after delivery, the blood samples were drawn at the time of 24 hours postpartum and then blood cells are classified and counted. The onset of lactation was confirmed by the maternal perception of breast fullness. The neutrophil-lymphocyte ratio and its relationship with the onset of lactation were analyzed by multivariable regression. Results: The neutrophil-lymphocyte ratios of the two groups were both elevated after deliveries. Based on the covariance analysis, after adjusting the baseline in full blood counts before delivery, the neutrophil-lymphocyte ratio in the cesarean group is higher than the ratio in the vaginal group after delivery (p =.000). Also, after adjustment of confounding factors, the multivariable regression analyses showed that increased neutrophil-lymphocyte ratio was correlated with delayed onset of lactation (95% CI 0.285-1.646). Conclusions: Compared with the vaginal delivery, Neutrophil-lymphocyte ratio in the cesarean section is higher and is related to a delayed onset of lactation. The mechanism for this delay onset of lactation may be due to the decreased mitochondrial DNA copy number and ATP production.
DOI: 10.17632/vd98rrh29h.1
title: The Effect of SiC Content on the Tribocorrosion Performance of SPS Produced Al-SiC Nanocomposites.

description: The research data includes the chronopotentiometry graph of the composites during tribocorrosion testing. The graph depicts the surface states of the composites during the interplay of wear and corrosion. From the respective images of the graphs, the galvanic coupling setups between the worn and worn areas can be deduced from the sudden shift of potentials as soon as the load was applied. After which the composites showed another shift to the more anodic region owing the role played by the reinforcement amongst others such supporting effect and increase of the hardness property of the composites. Furthermore, the SEM analysis of the wear track of the composites after tribocorrosion testing clearly shows the severe delamination and pull out of parts of the formed layer of the unreinforced aluminium matrix compared to that of the composites. On the composites, the formation of reaction products comprising of the reinforcement and the matrix led to the reduction of the coefficient of friction of the composites compared to that of the unreinforced alloy. It was also observed that the counter body used also deteriorated during the testing and led to the contamination of the wear track in all the samples tested.
DOI: 10.17632/z4sh59w8sw.1
title: MCBAP_DATA_SET

description: The data set contains the problem instances for the MCBAP problem under study.
DOI: 10.18462/iir.thermag.2018.0020
title: Study on layered beds arrangement for active magnetic refrigerator.

description: This study investigates the optimum structure of layered beds of manganese (Mn)-based alloys for an active magnetic refrigerator using one-dimensional heat transfer numerical analysis. The parameter used in the analysis is the Curie temperature interval. The active magnetic regenerator duct length is fixed at 150 mm. The analysis shows that the cooling power for a 2 °C interval and 13 types of material (length: 11 or 12 mm per material) is higher than that for a 6 °C interval and 5 types of material (length: 30 mm per material). The intersection point of the magnetic entropy change distributions of adjacent materials is at about 40% and 90% of the peak magnetic entropy change value for a 6 °C and 2 °C interval, respectively. Based on the results, high cooling power can be obtained when the intersection point is more than about 90% of the peak magnetic entropy change value.
DOI: 10.18462/iir.thermag.2018.0034
title: Simulations and design of a refrigerating device based on a rotating magnetocaloric disc.

description: The possibility of utilizing a Gd disc as an active magnetic regenerator (AMR) is investigated. We have designed a demonstration device based on a rotating disc with a fixed magnetic circuit covering one quarter of its area. The device implies zero thermal load with the operation fluid flowing through. Simulations are based on discretization of the heat transfer equations for the disc and the fluid domains using the finite difference method. The magnetocaloric effect (MCE) is included in the model as an instantaneous adiabatic temperature change of each element entering the magnetic field. Regenerative effect is obtained as at each radius of the disc the magnetocaloric material (MCM) operates switching its temperature around a different average, which decreases from periphery to centre. This allows the total temperature drop of the operational fluid to be several times larger than the adiabatic temperature change.
DOI: 10.18462/iir.thermag.2018.0044
title: Modelling of heat transfer processes in cooling cell with Ni-Co-Mn-In magnetic wires.

description: In this paper, the heat transfer processes in the three-dimensional cell of magnetic cooling containing Ni45Co5Mn37In13 Heusler alloy microwires are studied. Two variants of wires arrangement relative to each other are considered with equal volume and cell parameters. The temperature relaxation times and the velocity fields of the coolant are calculated. It was found that the temperature relaxation time, the distribution of the coolant velocities, and the transfer of heat energy depend on the way of the wires arrangement in the cell.
DOI: 10.17632/ygxk82g498.1
title: Dynamic temperature profiles in a poly-carbonate panel filled with phase change materials under test in a Dynamic Heat Flow Meter Apparatus

description: The dataset reports the temperature evolution in different points of a poly-carbonate panel filled with two different types of phase change materials. The dataset is obtained by performing tests with a Dynamic Heat Flow Meter Apparatus. More information on the tests can be found in the article "Sinusoidal response measurement procedure for the thermal performance assessment of PCM by means of Dynamic Heat Flow Meter Apparatus" published in Energy and Buildings, DOI: 10.1016/j.enbuild.2018.11.011
DOI: 10.18462/iir.thermag.2018.0010
title: Two-Dimensional multiphysics modeling of a magnetocaloric device and parametric study.

description: The modeling of the multiphysics phenomena that occur inside the active magnetocaloric regenerators requires the coupling of magnetostatic, magnetocaloric and thermo-fluidic models. The main objective of the contribution presented is to combine the very low resolution time of the multiphysics model with a good accuracy. In this context, a magnetostatic semi-analytical modelling has been developed in order to calculate the values of the magnetic field and the magnetic flux density at each point of the magnetocaloric regenerator volume. The magnetocaloric model calculates the magnetization and the magnetocaloric power density. A thermo-fluidic model computes the new temperatures in the fluid and inside the active magnetocaloric material. Indeed, the multiphysics model needs much less computation time than FEM and ensures a compatibility with an optimization process. The dependence of fluid displacement ratio and functioning frequency is assessed in order to determine the optimal working point for an imposed set of external conditions.
DOI: 10.18462/iir.thermag.2018.0011
title: Influence of binder and curing process on the magnetocaloric properties of bonded LaFeSiH alloys.

description: In this work, the influence of binder and curing process on magnetocaloric properties of bonded La(FexSi1-x)13Hy plates is studied. The epoxy resin, the poly-amide and the La(FexSi1-x)13Hy powders are mixed with aceton in different ratios.The hydrogen content, Curie Temperature(Tc),magnetic entropy change (△SM) and the adiabatic temperature change(ΔTad) are investigated. When the plates are cured at 40 ℃ for 60 min,the ΔTad remains almost the same as the powders’. And the mass fraction of the binder is 2.5 wt.%.
DOI: 10.18462/iir.thermag.2018.0012
title: Numerical analyses of a Multi-layered AMR with Manganese-based Materials.

description: The active magnetic regenerator (AMR) is expected to contribute to realizing a practical use of the magnetic heat pump in the room temperature. The characteristics of the magnetic material used for the AMR constitute a major factor determining the performance of the magnetic heat pump equipped with the AMR. Large magnetocaloric effects (MCEs) at the room temperature have been reported in the several research papers. Magnetic materials having the first-order phase transition show large MCEs in comparison with the second order phase transition materials such as gadolinium. While the first-order materials have large MCEs, the temperature range where they function is smaller than that of the second-order materials. Therefore, the multilayered AMR is necessary for obtaining a large temperature span in case of using the first order materials. We have conducted numerical analyses of the multi-layered AMR with manganese-based materials and discussed the design of multi-layered AMR using the first order materials as preparation for the experiments. We have found out that there is a possibility that a cooling capacity of about 15 W at a temperature span of 30 K can be obtained at 17 layers and Curie temperature difference of 2.5 K for each layer. It means that a unit will have a cooling capacity of 150 W when 10 AMRs are assembled as one unit.
DOI: 10.18462/iir.thermag.2018.0023
title: A self-regenerating electrocaloric cooler.

description: In this paper, we report a self-regenerating solid-state electrocaloric cooler that achieves a high ratio between the temperature span of the device and the electric-field-induced temperature change of the electrocaloric (EC) elements. The cooler consists of two layers of alternating rows of EC multilayer capacitors (MLCs) and insulating material. The layers move laterally relative to one another as the polarizing electric field switches synchronously. A demonstration device based on COTS BaTiO3 MLCs is fabricated and tested. The system achieves a temperature span of ~2.5 K with an applied field of 300 kV/cm. This is approximately five times the adiabatic temperature change of the MLCs.
DOI: 10.18462/iir.thermag.2018.0032
title: Study of the energy conversion chain in a thermomagnetic generator.

description: Thermomagnetic generators designed to scavenge electrical energy from a heat flow can be designed following different conversion chains. Here we numerically study a device based on a three steps conversion, from magnetic towards kinetic, and eventually electrical energy. This chain is assured by a magnetocaloric material (MCM) as active substance moving between the heat reservoirs on an elastic beam (polypropylene :60.6 x 26.6 x 1.2 mm3) designed to obtain an auto-oscillating system. The cantilever kinetic energy is recovered using piezoelectric patches (PZT 5a). After optimization of the patches size, our simulations give an output energy density of 0.03 mJcm-3. To achieve a further optimization we investigate the possibility to use the piezoelectric material both as a transducer and as an actuator to have a better control of the working thermodynamic cycle. In this way we show that an energy density up to 60.46 mJcm-3 can be achieved.
DOI: 10.18462/iir.thermag.2018.0036
title: Interstitial modification of La(Fe,Si)13 phase by acid solutions.

description: In this article we study a liquid medium route for hydrogenation of La-Fe-Si alloys utilizing diluted 0.83 M acetic(C2H4O2) and formic (CH2O2) acids, where the powdered alloy is immersed in the solution for periods up to 45 minutes depending on the nature of the acid solution. The alloys were characterized by XRD analysis to observe the modification of the lattice and undesired phase content after the hydrogen modification, as well as DSC analysis to characterize the nature of the Curie temperature (TC) transition. It was observed that there is a strong interplay between hydrogen insertion kinetics and La(Fe,Si)13 phase degradation: As the use of stronger acids may shorten the reaction period necessary for a full saturation of the hydrogen sites, uncontrolled exposure periods increase the formation of undesired phases, such as α-Fe. Furthermore, it was shown that this process can be a great alternative to gas-solid reactions used for these alloys, as results show TC shifts from 207 to 340 K in approximately 4 minutes of processing with formic acid, and from 207 to 338 K in 15 minutes of the powder immersion with acetic acid with minimal phase degradation.
DOI: 10.18462/iir.thermag.2018.0038
title: Performance assessment of solenoid valves as flow distributors for an active magnetic regenerator.

description: Active magnetic regenerators (AMR) face many challenges as an alternative technology, particularly for low capacity systems. For instance, in domestic refrigeration, a small increment in power consumption could result in low efficiencies, and the potential benefits of magnetocaloric-based devices would not be enough to support its application. As already reported in the magnetic refrigeration literature, hydraulic circuit components, especially flow control valves, can be the major contributors to total power input in AMR devices. Despite the variety of hydraulic circuit solutions proposed so far, no candidate clearly excelled in all technical criteria. The present work evaluates the performance of a pump and solenoid valve association as flow distributors for an AMR test apparatus. Power consumption, cooling capacity and the resultant overall thermodynamic efficiency were taken into account. Qualitative aspects originated from the experience of running the apparatus were also
considered in this assessment.
DOI: 10.18462/iir.thermag.2018.0006
title: Optimizing the electrocaloric effect by ab initio based simulations: the benefits of substitution.

description: We study the impact of Sr substitution on the electrocaloric effect (ECE) of BaTiO3 by means of ab initio based molecular dynamic simulations. The conventional ECE is maximal at the paraelectric to ferroelectric phase transition and the inverse ECE occurs at the paraelectric to ferroelectric phase transitions for all concentrations. These ECE peaks are systematically shifted to lower temperatures with increasing Sr concentration. This allows to enhance the ECE at and below room temperature. While the conventional ECE in the system is promising for multi-stack cooling devices, first results on concentration graded multilayers show that the internal boundary conditions may strongly reduce the response.
DOI: 10.18462/iir.thermag.2018.0009
title: Variable load control method for magnetic cooling systems.

description: In this study, we demonstrate that magnetic cooling system has significant energy saving advantage when operating under part load conditions. Part load operation refers to less load under constant temperature span, or constant load with less temperature span, or a combination of both, which are common features of refrigerators and air-conditioners. To achieve high efficient operation under part load, a close loop control strategy is proposed to automatically tune the operating frequency and flow rate based on the temperature of heat source heat exchanger. The proposed control method is robust for five different load variation profiles, which can guarantee to maintain temperature within ±1K from set-point. A case study is carried out for unitary air-conditioning application, which shows over 6 times of COP enhancement from full load to minimum part load ratio conditions, and the overall energy efficiency index doubles from the nominal COP value.
DOI: 10.18462/iir.thermag.2018.0016
title: Basic research on durability of Mn-based magneto-caloric material for magnetic heat pump.

description: In order to put a room temperature magnetic heat pump into practical use, the reliability of the heat pump device has to be confirmed. Recently, magnetocaloric materials (MCMs) mainly made of iron have been developed, but it is necessary to contact some liquid with MCMs for heat exchange, so it is important to evaluate the durability of the MCMs against contact with some liquid. In order to evaluate the durability of Mn-based MCMs, we added some kind of anti-rust agent to water and conducted an experiment to investigate the corrosion occurrence situation. In the experiment, the material for crushing was immersed in liquid for up to 4 weeks at room temperature, its change over time was observed, and the change in properties was periodically measured. As a result, it was observed that when rust preventives were not added, rust occurred after a few days, whereas the addition of rust inhibitors prevented rust formation. It was also confirmed that no characteristic change occurred by selection of an appropriate rust preventive agent. In addition, a durability evaluation test was conducted to see whether changes in the mechanical strength and magnetization characteristics of the Mn-based MCMs can be seen by repeatedly changing the magnetic field. Mechanical strength was measured with a Micro Vickers hardness tester. The magnetization measurements were carried out in a magnetometer equipped with a superconducting quantum interference device. In the magnetic field change of 0 to 1 T of about 400,000 times, the results are not particularly noticeable for the deterioration of magnetic properties and the change in mechanical strength.
DOI: 10.18462/iir.thermag.2018.0021
title: Numerical exploration of ferrofluid magnetic refrigeration based on convection principles.

description: Magnetic refrigeration is identified as a candidate to replace the dominant vapor compression cycle. To maximize the surface area of the magnetocaloric material, ferrofluids are useful and can be used simultaneously as refrigerant and heat source. Additionally, a combination with convection principles is sought to establish a self-pumping system. After validation of the numerical model, a linear gradient magnetic field Bmax of 1.5 T is applied over a 2D horizontal concentric annulus with L/D-ratio = 0.125. Bulk fluid assumption is used to predict the adiabatic temperature rise Tad in the Gadolinium – kerosene ferrofluid. A linear behavior is found for Tad, with Tad,max being 0.32 K for a volume fraction of 5%. Simulations show that thermomagnetic convection is the dominant principle as it strongly outweighs natural convection. This is underlined by the reformulated magnetic Rayleigh number, which is a factor 105 larger than the Rayleigh number.
DOI: 10.18462/iir.thermag.2018.0024
title: Experimental evaluation of a cabinet and heat exchangers emulated by an active magnetic regenerator.

description: Even though several magnetic refrigerator prototypes have been developed throughout the years, few attention has been given to the refrigerated cabinet and the actual heat exchangers. Such components have a large influence on the thermodynamic performance of the device as they dictate the operating point of the active magnetic regenerator (AMR) in terms of cooling capacity and temperature span. Therefore, in this work, the performance of a wine storage cabinet coupled to actual heat exchangers emulated by an AMR was experimentally evaluated. An experimental test apparatus was developed to emulate the operating conditions of the heat transfer fluid that would be provided to the heat exchangers by a hypothetical AMR. A set of heat exchanger and fan was chosen to evaluate their influence on the overall system performance. The experimental results were employed to validate a mathematical model developed to perform the integrated design of the heat exchangers and the AMR.
DOI: 10.18462/iir.thermag.2018.0025
title: Solid-state magnetocaloric cooler without heat switches.

description: In this work, the principle of magnetocaloric cooling in ferromagnetic materials based on the difference in the magnitudes of the magnetocaloric effect during magnetization and demagnetization was shown. The correct choice of the operating point and the shape of the switching pulses of the external magnetic field allows building an efficient thermodynamic cycle for the magnetocaloric cooling. Based on this principle, a solid state magnetocaloric cooler with a gadolinium-based magnet was experimentally demonstrated.
DOI: 10.18462/iir.thermag.2018.0028
title: Integrated design of a magnetic circuit and an active magnetic regenerator for a 100-W compact device.

description: In this work, we integrate a 1D active magnetic regenerator (AMR) model with a model of a magnetic circuit to study the coupled influence of regenerator and magnet dimensions on the device performance. The magnetic circuit is composed of two concentric Halbach cylinders formed by iron and Nd-Fe-B segments and optimized to match the desired ramp magnetic profile. The regenerators are modeled as prisms positioned in the gap between the cylinders and are composed of 3 layers of Gd-Y spheres. By varying simultaneously the external radius of the magnetic circuit and the regenerator height, we obtained an AMR design that can generate a nearly-instantaneous magnetic profile from 0 to 1.2 T, with a magnetic circuit of external radius 120 mm. The proposed design reaches a cooling capacity of 119 W at a regenerator temperature span of 35 K, with a COP of 2.5 and a second-law efficiency of 32.8%.
DOI: 10.18462/iir.thermag.2018.0039
title: Continuously operating elastocaloric cooling device based on shape memory alloys: development and realization.

description: Elastocaloric cooling based on NiTi exhibits an excellent cooling capability, due to the high specific latent heats activated by mechanical loading/unloading and the small required work input.

The current funding period of the DFG Priority Program SPP 1599 focuses on the development and realization of a continuously operating elastocaloric cooling device. A novel mechanical loading concept and a novel bundle concept of thin SMA wires enable a thermodynamically optimized cooling process by utilizing a minimal amount of SMA material in a compact design space and high cooling capability. The versatile realization of the device allows the independent variation of process parameters, thermal boundary conditions, and material parameters.

This work presents the design process from the development of the novel loading and heat exchange concept, the fluid management and the wire arrangement up to the fabrication and validation of an efficient continuously operating cooling device based on SMA.