dataesr/scientific-paragraphs-categorization huggingface dataset:
Conclusions This paper describes a method to interpolate the mean velocity field at a given time according to the value of a parameter that modified the aerodynamics of a cyclic flow. This technique was applied to the tumble motion inside the cylinder of a Miller cycle gasoline engine. The parameter on which the interpolation was performed was the VVT offset and the data were collected experimentally in a transparent engine using PIV measurements. The method used a proper orthogonal decomposition, which was chosen to reconstruct the average field with the first six modes of the POD. The maximum mean value error on the rotation rate between the mean and the reconstructed fields of the POD was 2. 3%. The error of the position of the center of rotation was below 1 mm. The quality of the interpolation was then estimated using the measured fields for VVT offset values outside the POD.
Acknowledgments This work was financially supported by  European Commission  through the  ERC  project  SUPRA2DMAT  ( GA-833707 ), the  Graphene Flagship Core 3 project  ( GA-881603 ), the  Marie Sklodowska Curie ETN  projects  ULTIMATE  ( GA-813036 ) and  BORGES  ( GA-813863 ), the  AMI  project funded by the  ERA-NET EuroNanoMed III program , the  European Union  and the  Agence Nationale de la Recherche (ANR)   GA-ANR-17-ENM3-0001-01 , the  Labex  project  CSC  ( ANR-10LABX-0026 CSC ) within the  Investissement d'Avenir program   ANR-10-IDEX-0002-02 , the  International Center for Frontier Research in Chemistry (icFRC)  and the  Institut Universitaire de France (IUF) ,.
For both the spray breakup models, the number of actual droplets per parcel after breakup is calculated based on principle of mass conservation. The time step is controlled by the user defined maximum Courant number 𝐶𝐶𝑜𝑜 𝑚𝑚𝑚𝑚𝑥𝑥 = Δt Δx , where Δx is the grid size. In this study a fixed PPS of 2 × 10 7 and a 𝐶𝐶𝑜𝑜 𝑚𝑚𝑚𝑚𝑥𝑥 of 0. 3 are used. All the calculations are performed using the opensource software OpenFOAM version 6. 0.
As shown in Fig. 5 (b), representative Co/CNF-HDP9 was prepared by homogeneous deposition precipitation (HDP) with cobalt loading of 9%. The sample exhibited rather long fibers decorated with 14 nm cobalt particles. 51 The TOF and hydrocarbon selectivity were independent of the cobalt particle size for the catalysts with the Co particle sizes larger than 6 nm, but both activity and selectivity to the C 5 + decreased for the catalysts with Co particle sizes below 6 nm. Fig. 5 (e) shows that the cobalt-specific activity achieves the maximum value for Co/CNF with a cobalt particle size of 6 nm. The TOF was calculated using the dispersion obtained from X-ray photoelectron spectroscopy. The TOF data are plotted in Fig. 5(d ). It can be concluded that TOF is rather constant with a value of around 10 À2 s À1 for the cobalt particles ranging from 6 to 27 nm.
Acknowledgements This work was supported by  Liaoning Natural Science Foundation  ( 2020-MS-021 ). Supported by  LiaoNing Revitalization Talents Program  ( XLYC1807077 ). Dalian National Laboratory for Clean Energy (DNL) ,  DNL Cooperation Fund ,  CAS  ( DNL180402 ). The authors acknowledge financial support of the  French National Research Agency  ( NANO4-FUT, Ref. ANR-16-CE06-0013 ) and from  European Union  ( Interreg V project PSYCHE ).
Acknowledgments: The authors thank greatly the following organizations for funding the PhD scholarship of M. E. K ( ANR and Labex LANEF du Programme d'Investissements d'Avenir :  ANR-10-LABX-51-01 , of J. S. W. ( Fondation Nanosciences ) and of C. H. (CEA). The authors also thank  ANR  and  AID/DGA  for the financial support ( ANR-18-CE42-0012 ). SyMMES laboratory is part of  Labex LANEF, Labex ARCANE  and  CBH-EUR-GS  ( ANR-17-EURE-0003 ).
Palette components Generally, in order to propose a surrogate fuel, a palette of chemical compounds should a priori be identified before any formulation optimization process is carried out  [23]. The pure components used as palette database in this work were taken from some preceding studies and reviews that considered them as diesel surrogates, as shown in Table  1  which also presents their properties to constitute a database. Density at 15 °C was chosen instead of that at 20 °C, as used in previous work  [24] , and this was the most used one in literature and also in standard norms  [25, 26]. The palette was also prepared using most recent references and the four organic classes are represented: n-alkanes, isoalkanes, cycloalkanes and aromatics.
Surrogate formulation optimization The program performed for the optimization of a surrogate composition was developed using the Excel Solver and the numerical method of the GRG to optimize the objective function used: F obj = 3 j =1 P targ i -P surr i P targ i 2 (5) where P targ i is the target property considered (density, cetane number and viscosity) of a considered fuel to emulate P surr i the corresponding mixture property of the optimized surrogate. P surr i was estimated using appropriate mixing rules expressed in terms of the component's mass or molar fractions x i to optimize according to the following two constraints: • Σx i = 1 • The calculated properties must respect international norm values as presented in Table  2 , and a deviation was calculated to evaluate the accuracy of the estimated property of the optimized surrogate as follows: Deviation P = |P targ -P surr | P targ (6) where Deviation P is the deviation of property P , P targ is the target property of diesel to emulate and P surr is the property of the blend of the optimized surrogate estimated using mixing rules.
That is why the surrogates obtained are recommended for blends with less than 50% in biodiesel. Also, the biodiesel percentages in the studied blends affect the composition of the proposed surrogates and also the accuracy of its target property estimation. Future work will focus on the preparation and analysis of the surrogates obtained on a laboratory scale, as well as an enhancement of the palette and its enrichment with the addition of esters and additional target properties. Furthermore, the program developed is adaptable, allowing for the expansion of the database and target properties for the same and other fuels.
The compression ratio is also essential for combustion process of engine. It is beneficial to increase the compression ratio to achieve better cycle performance, but it is also theoretically limited by the potential of knock. In order to perform a research about the compression effect and efficiency boundary of oxy-fuel SI engine, Wu et al. [67][71]  have established a thermodynamic model using STANJAN software of Reynolds and the ideal ICRC process. It was indicated that injected water is helpful for oxy-fuel SI engines to reach a higher compression ratio. It was also found that with the compression ratio increasing from 9. 2 to 14, cylinder pressure increases obviously and IMEP also gets an increment from 0. 68 to 0. 78 MPa under no water injection condition and from 1. 09 to 1. 55 MPa under 140 mg water injection condition, respectively.
This instrument was equipped with a monochromatized Al Kα source (15 mA, 14 kV) and a charge compensation gun. Binding Energy values were corrected by using the C 1s core level as reference at 284. 8 eV. Spectral analysis was carried out using Casa XPS software. A mixed Gaussian/Lorentzian (70/30) line profile was adopted for peak deconvolution. Calculations of surface atomic composition were conducted by relative sensitivity factor analysis method by using Shirley background substraction type.
Acknowledgements The authors acknowledge financial support by the  EU-Partial- PGMs  project ( H2020-NMP-686086 ). Chevreul Institute  ( FR 2638 ),  Ministère de l'Enseignement Supérieur et de la Recherche ,  Région Nord -Pas de Calais  and  FEDER  are acknowledged for supporting and funding partially this work. We also thank  Martine Trentesaux  and  Pardis Simon  who conducted XPS measurements and  Olivier Gardoll  for thermal analysis.
Acknowledgments This work was developed within the scope of the project  CICECO-Aveiro Institute of Materials ,  UIDB/50011/2020 & UIDP/50011/2020 , financed by national funds through the  FCT/ MEC  and when appropriate co-financed by  FEDER  under the  PT2020 Partnership Agreement. Inês S. Cardoso  acknowledges the PhD grant  SFRH/BD/139801/2018.
Prior to each DRM reaction, the catalysts were reduced at the same temperature for 60 min in the gas stream of 5 vol % H 2 in Ar. The outgases were detected by a gas micro chromatography equipped with a TCD detector to analyze the composition of products. The calculation of conversions of CH 4 and CO 2 and H 2 /CO was described elsewhere. 47 The experimental error was ±5%. Catalyst Characterization. Textural properties were determined by the nitrogen adsorption desorption measurements in a Belsorp Mini II instrument at -196 °C. Prior to measurement, the catalysts were pretreated under a vacuum condition at 200 °C for 120 min. The phase structure of the catalysts was evaluated by XRD (X-ray diffraction) analysis on a diffractometer of DX-1000 CSC using a source of Cu Kα X-ray. The data was collected in the 2θ range of 10-80°.
The scan step size was 0. 03°. The reducibility of catalysts was determined by the H 2 -TPR (temperature-programmed reduction of H 2 ) on a BELCAT-M instrument. The mass of catalyst was about 60 mg. Before the test, the catalyst was cleaned at 150 °C under helium flow for 30 min. Then, the sample was reduced under a mixture flow of 5 vol % H 2 in Ar with a heating rate (10 °C/min) from 100 to 900 °C. The surface elements of catalysts were characterized by XPS (X-ray photoelectron spectroscopy) analysis, which was carried out on a KRATOS spectrometer instrument with monochromated Al radiation. All of the data (the electron binding energy) were referenced to the C 1s peak at 284. 5 eV. 29 The morphology of catalysts was determined by TEM (transmission electron microscopy) experiments, which was conducted on the FEI Tecnai G2 20 Twin apparatus.
The coke of used catalysts was obtained by TGA (thermogravimetric analysis). The mass of the sample was 10 mg. The sample was heated from 30 to 800 °C with a 5 °C•min -1 rate under air of 60 mL•min -1. Raman spectroscopy experiments were conducted on an objective of X50LWD with a laser of 532. 17 nm, a grating of 600 gr/mm, a filter of D1, and a hole of 200 μm. The data was collected from the wavenumber values of 40-4000 cm -1. Herein, Raman characterization was carried out for the in-depth study of carbon species deposited on the used catalysts. 33, 34 The temperature-programmed desorption of NH 3 (NH 3 -TPD) method was carried out using a BELCAT-M instrument. Before the test, the sample (60 mg) was reduced at 700 °C under a mixture flow of 5 vol % H 2 in Ar and then cooled down to 50 °C under He flow.
X-Ray diffraction analysis (XRD) The upper surface mineralogical analysis of another of the three plates was carried out by DRX to detect and identify the crystalline phases present and their possible evolution over time. The apparatus used is a Bruker D8 Advance diffractometer CuKa equipped with a germanium monochromator. The sample did not undergo any preliminary preparation to avoid destabilizing the crystallized phases present on the surface. The measuring parameters used were as follows: i) angular range 5 to 90°, ii) angular measuring step of 0. 021°, iii) counting time in 158 s steps. The quantification of the phases present, by the Rietveld method in particular, was not considered relevant, given the data acquisition conditions (preferential orientations, representativeness of the investigated volume, choice of relevant interpretation parameters, mineralogical complexity, etc.
Simulation Tool and Main Hypotheses A conceptual design of the methanol synthesis process is implemented in the ASPEN HYSYS v8. 8 Computer-Aided Design (CAD) software  [26]. Simulations are performed in order to determine energy requirements, the design of the main equipment, and the operating conditions in the processes. The obtained data (heat duties, sizes, etc. ) are used to calculate the equipment costs through correlations. For example, the capital cost of compressors is a function of the supplied mechanical power calculated by the CAD software. The following hypotheses and conditions are considered in the simulations for the calculation of the mass and energy balances:.
The main process units are modelled assuming some hypothesis and simulated with the Aspen Hysys CAD software. The techno-economic analysis, based on a factorial method, led to the calculation of the levelized cost of methanol. The main hypotheses are an actual process life time of 20 years, a discount rate of 7. 4% and a surrounding factor of 1. 8, a consistent value used for existing industrial fields. The levelized costs of methanol are equal to 228 and to 268 €/ton for case studies A1 and A2 respectively. These methanol production costs are slightly higher than those for methanol produced from fossil fuels. The investment cost due to compression steps represents an important contribution (approximately one-third of the CAPEX) partly caused by the working conditions of the methanol synthesis and of the CO 2 absorption.
The [VO(acac) 2 ] metal center comprises a vanadyl ion VO 2+ coordinated by two chelating bidentate β-diketonate ligands (Figure  1 ). The coordination geometry around the penta-coordinated V IV metal center is a distorted square pyramid, as already reported in previous studies. 33 This molecule crystalizes in a P1̅ space group (no. 2), for which the only point symmetry element is inversion. The asymmetric unit contains one molecule and the primitive unit cell contains two molecules, for a total of 60 atoms (see Table  1 ). The crystallographic structure has been already solved using high-resolution data in 1995 34 at 294 K. Here, we present new data collected at 300 K, 1 300K , and 100 K, 1 100K , both on the same sample (Table  S1 ). A good agreement between 300 and 294 K datasets is found, while the shrinking of cell parameters at 100 K is highlighted in Table  1.
Experimental Apparatus and Data Analysis. THz spectra were measured by time-domain spectroscopy using a table-top experimental setup working in a transmission configuration. It allows one to achieve a very high signal-tonoise ratio, higher than what is usually obtained in the standard far-infrared investigation (FTIR). Furthermore, the nontrivial data analysis allows one to decouple the signals arising from The Journal of Physical Chemistry C the multiple reflections inside the sample, i. e. , the Fabry-Peŕot effect. The THz-TDS spectrometer is a home-built system based on optical laser pulses (T-light 780 nm fiber laser, MenloSystems) and low-temperature GaAs photoconductive antennas. The emitted THz radiation (pump) is collimated and focused on the sample by a couple of off-axis parabolic mirrors.
The signal transmitted through the sample is again collimated and focused on the detector, a second photoconductive antenna, biased by a second optical pulse (probe). It results in a photocurrent that is measured by a lock-in amplifier and an acquisition board. The amplitude of the THz electric field is measured by varying the time delay between the pump and probe pulses so as to reconstruct its time profile. The homemade software in Matlab code was implemented to acquire the processed signal together with the reading of the delay line encoder and retraces the final time-dependent THz field. The whole THz setup is placed in a nitrogen-purged chamber to eliminate the strong absorption of water vapor. To improve the data quality, the effects of external perturbations during the acquisition (e.
901-5), the powder was pressed by means of a manual hydraulic press (about 0. 8 GPa); (1 b ) a pure HDPE pellet on which we deposited a few drops of [VO(acac) 2 ] dichloromethane solution of several microns by the drop-casting method. Computational Methods. Vibrational Properties. For the density functional theory-based calculations, we used the [VO(acac) 2 ] crystallographic unit-cell coordinates. The temperature effects on the crystal structure were tested exploiting the X-ray data collected at 100 and 300 K. The availability of these data allowed to optimize the molecular structure keeping the experimental cell parameters fixed,  35  in such a way the temperature effects can be indirectly accounted. The simulation of cell parameters at finite temperature can be accomplished only via dynamical DFT methods (ab initio molecular dynamics).
The acidity of samples was examined by NH 3 -TPD using an AUTOCHEM 2910 (Micromeritics, Aachen, Germany). The solid was pre-treated at 550 • C (ramp 10 • C/min) during 2 h, under air flow (30 mL/min). Then, it was exposed to 5 vol% NH 3 in He (30 mL/min) for 30 min, and subsequently with He (30 mL/min) for 30 min to remove the physiosorbed ammonia. Finally, the NH 3 desorption was performed in helium flow (30 mL/min) from 100 to 550 • C (the heating rate was 5 • C/min). The elemental analysis of sample surface was investigated by X-ray photoelectron spectroscopy (XPS) on a KRATOS spectrometer with an AXIS Ultra DLD (Manchester, UK). All the data were calibrated using the C 1s peak at 284. 6 eV, as described elsewhere  [43].
The conductivity values averaged over 60 min (around 60 data points) were used. The cell constants were determined using a 0. 01 m KCl standard solution. The electrolytes′ viscosity was tested in a dry room environment utilizing an Anton-Paar MCR 102 rheometer, applying a constant shear rate of 10 s -1 , and using a Peltier system for cooling/heating. The viscosity values averaged over 2. 5 min (50 data points) were used. The Raman measurements were recorded on a RAM II FT-Raman module of a Bruker Vertex70v FT-IR spectrometer with a laser wavelength of 1064 nm and laser power of 300 mW. SAXS patterns were collected at the SWING beamline 1 of the Soleil Synchrotron near Paris (France), with monochromator set at 16 KeV. Using a EIGERX 4M detector at 0. 871 m from the sample, diffraction patterns were recorded for reciprocal spacing q = 4π sin(θ)/λ varying between 0.
0126 and 1. 4 Å -1 , that is, repetitive distances d = 2π/q ranging from 500 to 5 Å. Beam size was 375 × 25 µm² (V × H). To ensure the best background subtraction, the empty 1. 5 mm o. d. (1. 48 mm i. d. ) quartz capillaries were measured before the sample injection, and each background was used on the corresponding sample, even if the difference between the scattering patterns of the empty capillary was negligible. The samples were injected into capillaries, which were sealed with epoxy glue to avoid evaporation and water contamination. The exposure time was set to 500 ms and five consequent patterns were collected and 1D SAXS curves were obtained by circular averaging of the 2D images using the Foxtrot software. SEM images were obtained using a Zeiss LEO 1550 microscope. The cross section of the lithium electrodes was made with a scissor in the glove box.
Moreover, Venkateswaran et al. [30, 31]  and Zhang et al. [32]  reported that the use of the concept allowed them to significantly improve parameterization of their experimental databases on turbulent burning velocities, obtained from lean syngas-air flames. Nevertheless, the present authors are not aware on the use of the concept in CFD research into turbulent flames, with the exception of a single work  [42]. However, in that paper, fuel blends were not considered, and combustion chemistry was reduced to a single reaction. Accordingly, there is a need for assessment of the leading point concept in CFD research into turbulent combustion of fuel blends by allowing for complex combustion chemistry. The present paper aims at filling this knowledge gap by performing RANS simulations of recent experiments done by Venkateswaran et al.
In the present work, these standard equations were numerically solved by running the module OPPDIF  [57]  of CHEMKIN-II software  [58]  and activating options Multicomponent and Thermal Diffusion. When simulating weakly strained flames, the parameters GRAD and CURV, which controlled the spatial resolution, were set equal to 0. 05 each. At high strain rates close to extinction points, these parameters were decreased to obtain converged results that were weakly sensitive to a further decrease in GRAD or CURV. Typically, both parameters were equal to 0. 005 and the number of grid points was about 5000. In a few cases, GRAD and CURV were as small as 0. 003, with the number of grid points being about 15 000. Distance between the inlet boundary (associated with a nozzle in Fig. 1 ) and the stagnation plane was set equal to 10 mm.
Acknowledgements SV gratefully acknowledges the support from  Prof. Arnaud Trouv  e ( University of Maryland, College Park ) and  Dr. Michael Henneke  ( John Zink Company, LLC ). AL gratefully acknowledges the financial support provided by  CERC. The authors are grateful to  Dr. Venkateswaran  and  Prof. Lieuwen  for providing their experimental data. r e f e r e n c e s.
A combination of PIV and PLIF experiments was realised by inserting the PLIF laser pulse between the two PIV laser pulses. The green laser beam was combined with the UV beam using the same optical lenses to produce a 2D laser sheet, 0. 2 mm thick and 50 mm high, positioned on the axis of symmetry of the flame. Both the inner and outer streams were seeded with ZrO2 particles using a home-made cyclone seeder. Particles illuminated by the green laser beams were imaged using a double frame CCD camera (Jai TM4200CL, 2048 × 2048 pixels). The PIV vectors were obtained by cross-correlation of the PIV images using the Dynamic Studio software (Dantec Dynamics) with final interrogation windows of 8 × 8 pixels, yielding a single velocity vector measurement on a 2D grid with 200 μm spacing.
Soot inception, growth, aggregation and oxidation scenario The combined use of OH-PLIF, PAH-PLIF, PIV and LII results can provide a wealth of information on the formation of soot. The following discussion demonstrates of the importance of combining laser diagnostics to distinguish the processes governing soot formation and consumption. This potential is illustrated in Fig. 6 , where overlays of the instantaneous and averaged OH, PAH and soot distributions are plotted for case 2. A detailed observation of these 2D distributions indicates that several distinct areas, associated with the different steps of soot formation and oxidation, can be identified. PAHs and soot volume fraction are strongly dependent on their respective rates of production and consumption. The combined results from these measurements provide a new and comprehensive database that will be useful for the validation of soot models in swirled and stratified flames.
Co and Zn K edge XAS spectra were recorded in air in order to characterize the initial state of the catalyst and then under He (100 mL min -1 ) at room temperature. Then, the cell was heated to 300 °C at a rate of 5 °C min -1 under an He flow, dehydrating the sample. The total pressure was further raised to 50 bar. During this pretreatment, XANES spectra were recorded continuously to observe the change in the metal oxidation state and EXAFS spectra were recorded at the end. Then, CO 2 hydrogenation was carried out by introducing 50 mL min -1 of the reaction mixture (20% CO 2 :79% H 2 :1% Ar) while the pressure was kept at 50 bar. The reaction was stopped after 20 h, and the last EXAFS spectra were merged to compare the final states of the catalysts. Processing of Spectra. All XAS data were processed using the FASTOSH package.