dataesr/scientific-paragraphs-categorization huggingface dataset:
Funding: This research was funded by  Ministry of Higher Education, Malaysia (MOHE)  under  Fundamental Research Grant Scheme  (FRGS), number:  FRGS/1/2018/STG07/UTP/02/1. Also, our sincere gratitude goes to the  Deanship of Scientific Research at Prince Nourah bint Abdulrahman University  through the  Fast-track Research Funding Program.
5406 Å). A step of 0. 02°with an acquisition time of 0. 5 s was used. Thermogravimetric analysis (TGA) and differential scanning calorimetric analysis (DSC) were performed with a TA Instrument SDT-Q600. Experiments proceeded under air flow (100 mL min -1 ), where spent samples were heated up to 700 °C (10 °C min -1 ). Pure alumina was used a reference. X-ray photoelectron spectroscopy (XPS) experiments were carried out using an AXIS Ultra DLD Kratos spectrometer equipped with a monochromatic AlKα radiation (1486. 6 eV) operating at 225 W (15 mA, 15 kV). Binding energies were calibrated according to the C 1s core level set at 284. 8 eV. Spectra of C 1s, O 1s, Zn 2p, Zn LMM and Ta 4d were analysed using the CasaXPS software. 42 Spectra decomposition was performed via mixed Gaussian-Lorentzian peak fitting; semiquantitative analysis was performed after a Shirley-type background subtraction.
3 h -1. After 1 hour on stream, the feed was switched to an ethanol-pyridine mixture containing 5 mol% of pyridine (Fisher, 99%); the reactor lines were kept above 125 °C to avoid condensation. After 1 hour of pyridine co-feeding, the feed was returned to pure ethanol. The reactor output was monitored with an online GC-FID throughout the experiment. Ethanol conversion (X, %), the selectivity towards each product (S i , %), the molar yield of each product (Y i , %) and the molar productivity of butadiene (P BD , mmol BD g cat -1 h -1 )eqn (1), (  2 ), (  3 ) and (  4 ) respectively-were used to describe catalytic activity, where c i represents the number of carbon moles measured for a given compound i. When initial values are concerned, such as the initial butadiene productivity, they represent the value obtained by extrapolating to zero the data obtained over time on stream.
1 eV. A Wagner plot, which provides rapid visualization of the modified Auger parameter by plotting the Auger electron KE in function of the photoelectron BE, is illustrated in Fig. 3  and compares the chemical environment of Zn in ZTT-1 to other Zn samples available in the NIST database. As can be seen, the modified Auger parameter of Zn in the TUD-1 material is different from that of metallic Zn, but also of ZnO. Instead, the Wagner plot indicates that the chemical environment of Zn in ZTT-1 is closer to that of natural zinc minerals, such as of zinc silicates, notably of hemimorphite supported on SiO 2 , or Zn(OH) 2 ,  53, 54  suggesting it is incorporated within the silica matrix of ZTT-1, rather than as extra-framework oxide particles that may form during the TUD-1 synthesis. Regarding the Ta 4d core level (Fig.
Cross sections for Zn 2p, Ta 4d and Si 2p were obtained from the relative sensitivity factor library available from Kratos Analytical. The detector efficiency of each parameter can be further defined as: I p I s XPS ¼ p s b Â D p D s Â σ p σ s Â β 2 2 Â ð1 þ e Àβ 2 Þ ð1 À e Àβ 2 Þ Â ð1 À e Àα1 Þ α 1 ð5Þ β 1 ¼ t λ ss ; β 2 ¼ t λ ps ; α 1 ¼ d λ pp ; ð6Þ where t is the empirical thickness of the support, estimated from its density and specific surface area as t = 2/ρ s × S, and d is the average particle size, a number with the value of zero if homogeneous dispersion is assumed. The mean free path of escaping electrons (λ) was calculated according to the Tanuma, Powell and Penn formula  60  using the QUASES-IMFP-TPP2 M software. 61 ig. 4  represents the experimental XPS intensity ratios (a) Zn/Si and (b) Ta/Si as a function of the bulk ratio determined by ICP-AES; the experimental points are compared to the red lines representing the theoretical intensity ratio predicted by the K-M model corresponding to the monolayer limit where (1 e -α1 )/α 1 = 1, that is to say the maximum dispersion of the supported phase that can be measured with the XPS technique.
Acknowledgements Oliver Gardoll  is acknowledged for performing the temperature-programmed experiments. Authors acknowledge the support from the  French National Research Agency  ( ANR-15-CE07-0018-01 ). Chevreul Institute  ( FR 2638 ),  Ministère de l'Enseignement Supérieur, de la Recherche et de l'Innovation ,  Région Hauts-de-France  and  FEDER  are acknowledged for supporting and funding partially this work.
Theory High level electronic structure calculations were carried out at the internally contracted multireference configuration interaction (MRCI) level employing the MOLPRO package  22  and the aug-cc-pVTZ basis set. The active space selected includes the 2s and 2p orbitals of C and O atoms and the 1s orbitals of both H atoms, leading to 10 active orbitals (See ESI and Fig. S4  †  ) while the 1s orbitals of carbon and oxygen were kept frozen. The calculations, performed in C s symmetry, include the state averaging of 4 states of A symmetry and 3 states of A symmetry of H 2 CO + along with the ground state 1A and 1A of neutral H 2 CO. For the electronic states of the cation, 11 electrons are included in the active space while 12 for the two states of the neutral formaldehyde. Potential energy curves have been computed for both the H-atom loss and the (CO+H 2 ) + channels.
Acknowledgements We thank  Garikoitz Balerdi  for his help in the first stages of this project. This work was performed at the DESIRS beamline. We acknowledge SOLEIL for provision of synchrotron radiation facilities under proposal number 20141243, and  J. -F. Gil  for his technical assistance. This project has received funding from the  European Union 's  Horizon 2020 research and innovation programme  under the  Marie Sklodowska-Curie  grant agreement No  842539  ( ATTO-CONTROL ) and has been financed in part by the  Spanish MINECO  (grant  CTQ2015-65033-P ) and the  Spanish Ministry of Science and Innovation  (grant  PGC2018-096444-B-I00 ).
■ ACKNOWLEDGMENTS We appreciate helpful discussions with  Kurt Kremer  and  Marcus Muller. We are grateful to  Burkhard Dunweg  for critical reading of our manuscript and useful comments. We are grateful to the  Deutsche Forschungsgemeinschaft (DFG, German Research Foundation ) for funding this research: Project number  233630050-TRR 146. H. M. acknowledges a generous grant of  CPU  time of the  High Performance Computing Center of the University of Strasbourg  (funded by  Equipex Equip@Meso  and CPER Alsacalcul/Big Data). P. V. and K. D. also acknowledge the contribution of the  COST Action   CA17139.
Reduced catalysts were prepared under inert conditions in an N 2 glovebox and transferred to the XPS apparatus using a custom-built air-tight transport vessel. All spectra were analyzed with CasaXPS, charge corrected against the C 1s binding energy of adventitious carbon at 284. 8 eV, and were fitted using a Shirley background. X-ray absorption spectroscopy (XAS). The reduction and structure of the catalysts were studied using operando XAS. Data was collected at the Ni K-edge (8. 3 keV) and Mn K-edge (6. 5 keV) in transmission mode at the Dubble BM26A beamline at ESRF, Grenoble, France. The energy was selected with a Si (1 1 1) monochromator and calibrated with Ni (E 0 = 8333 eV) and Mn (E 0 = 6539 eV) foil, respectively. Collected XAFS data were background subtracted, normalized, and fitted using linear combination fitting (LCF) as implemented in the Athena software package  [33].
At the Ni Kedge, the fresh (calcined) sample and the Ni foil served as references for the oxidized and metallic state of the catalyst for LCF. At the Mn K-edge, the Mn oxidation state was estimated from the energy at the half-edge jump. Linear regression of reference XANES spectra from MnO 2 , Mn 3 O 4 , Mn 2 O 3 , MnO(OH), and MnO were used to correlate half-edge jump energies to the Mn oxidation state. EXAFS analysis on k 3 -weighted Ni K-edge data was performed with Artemis. Scattering paths were calculated with FEFF6 using relevant crystal structures  [33]. The amplitude reduction factor S 0 2 was determined by fitting the first and second shell Ni-O and Ni-Ni coordinations to 6 and 6 respectively of a b-Ni(OH) 2 reference sample at the Ni K-edge (8. 3 keV). EXAFS analysis for Mn K-edge measurements was performed with Viper.
Combining Ni and Mn K-edge XANES data shows that for NiMn (0. 25)/SA, nearly all Mn is reduced to the +2 oxidation state prior to the onset of Ni reduction, and that the presence of Ni facilitates Mn reduction. Structural information about the active phase was obtained with EXAFS on the Ni and Mn K-edges. EXAFS spectra obtained on the Ni K-edge were background subtracted in Athena, and fitted in Artemis using single scattering paths calculated with FEFF6. Table  4  summarizes the path distances and coordination numbers determined for calcined and reduced catalysts on the Ni K-edge. The k 3 -weighted Fourier-transformed EXAFS spectra (not phase corrected) are plotted in R-space in Fig. 10. After calcination, both Ni/SA and NiMn(0. 25)/SA catalysts could be fitted with Ni-O (2. 08 Å) and Ni-Ni (2.
The shift is likely due to a higher CO coverage. Moreover, by comparing the relative contributions from (sub)carbonyl (>2000 cm À1 ) species with those from bridged (<2000 cm À1 ) species we clearly see that the NiMn(0. 25)/SA catalyst has a larger proportion of (sub)carbonyls than Ni/SA, suggest-ing a larger build-up of CO on the Ni metal surface. These findings are consistent with the experimental and theoretical data obtained in our previous works, in which the presence of defective MnO clusters on the Ni nanoparticles enhanced CO 2 activation to yield CO adsorbed on the metallic Ni surface  [32]. The role of H 2 could be the formation of oxygen defects in the Mn-oxide clusters. Additional surface species were identified by IR spectroscopy during methanation. Below 100 °C, bicarbonates were observed on both catalysts from characteristic asymmetric and symmetric m(OCO) vibrations at 1644 cm À1 and 1440 cm À1 , respectively.
Acknowledgements The authors acknowledge financial support from the  Netherlands Organization for Scientific Research (NWO)  and  BASF  for a TA-CHIPP grant. The authors thank the staff at the  BM26A Dubble beamline  at the  ESRF (Grenoble, France)  for the allocation of beam time (proposal no. 26-01-1166 ). We thank  Tobias Kimpel ,  Valery Muravev , and  Yujie Liu  for their assistance during the XAFS beam time. We thank  Mrs. Adelheid Elemans-Mehring  for performing the elemental analysis. We thank  Dr. Mengyue Wu  and  Dr. Frans Tichelaar  for the STEM-EDX measurements performed at  Delft University of Technology. We thank  SASOL  for providing the SIRAL20 catalyst support. Gabriella Garbarino  acknowledges the  University of Genova  for financial support from the ''Mobility.
Then, a CO 2 :He (1:9) mixture was flowed into the cell with a flow rate of 100 mL min -1 and the cell was heated up to 750 °C with a temperature ramp of 10 °C min -1. XANES spectra were recorded continuously during both DRM and TPO under CO 2 to observe the change of the metal oxidation state. X-ray absorption spectroscopy (XAS) data were analyzed using the HORAE package, a graphical interface to the AUTOBK and IFEFFIT code  [28]. After XANES spectra normalization, quantification of Co phases during DRM and CO 2 -TPO was computed by linear combination fitting using spectra of a fully reduced (metallic Co) and an oxidized (CoO) catalyst.
This dependence is consistent with the mechanism proposed in previous studies  [17, 18] , in which C-H bond activation in CH 4 is the rate-determining step on the Co surface, the sites of which are competitive to surface oxygen species from CO 2 activation. A similar kinetic dependence was observed in our previous study for the NiCo catalysts and the work by Chin and coworkers for Co catalysts  [18]. The resulting high surface coverage of surface oxygen species at steady state explains the high tolerance toward coking as surface O species may react with surface C species before its accumulation. together with a Co foil reference spectrum, obtained from SSHADE database  [37]. We therefore used the DFT calculation to determine the location and state of B in the Co surfaces. Furthermore, our simulations indicate that the presence of interstitial B in Co-extended surfaces led to spontaneous surface reconstructions during local geometry optimization (Fig.
The potentiostat was controlled by NOVA 2. 1. 4 software. The frequency selected was 1 Hz, the amplitude was 10 mV, and the step potential was 10 mV. We assumed that the electrochemical cell behaves as a Randles circuit. The analytical signal, Y, used to plot the AC voltammograms was determined by equation (  1 ), as it was described previously  [48] : 𝑌 = - 10 6 𝜔𝑍 𝐼𝑚 𝐴 -𝐶 𝑑 ( 1 ) where  is the angular frequency (rad s -1 ), ZIm is the imaginary part of the impedance (), A is the surface area of the interface (A = 1. 96 × 10 -5 cm 2 ) and Cd is the double layer capacitance (µF cm -2 ) determined in the absence of analyte. Professional chromatography software controlled the 882 Compact IC plus instrument and its peripherals.
Acknowledgements We thank the  Deutsche Forschungsgemeinschaft  through the  International Research TrainingG roup "Selectivity in Chemoand Biocatalysis" (GRK 1628 ) for financial support,  Prof. D. Stalke ,  K. -N. Truong ,  F. Ritter  and  M. Paul  for assistance with Xray crystallography,and  Dr. G. Fink  for NMR measurements.
Electrical characterization and data processing The gas sensing properties of the prepared SnO x and ZnO forcespun materials were studied using a conductometric characterization circuit (fig. 2a ). For that, the MOs forcespun powders were deposited on a glass microsensing platform with interdigitated gold electrodes separated by a 10µm-gap (fig. 2b ). Afterwards, the prepared sensors were inserted inside a closed chamber equipped with gas inlet and outlet connectors and a rotating fun. Pure air was generated using dry air generator and served as carrier gas through the sensing chamber during the whole measurement cycle. The air flow across the chamber was maintained stable at 50 sccm using a Mass flow controller (MFC) system. The target vapor was injected into the test chamber with defined concentration using a micro-syringe.
The sensor response was defined as the ratio , where Ra and Rg are the resistance of the sensor in reference pure air and after exposure to target vapor, respectively. Whereas the response time was defined as the time to reach 90% of the total resistance change in the gas adsorption stage. The sensitivity of the sensor based on SnO x and ZnO ultrafine fibers was investigated by measuring the sensor response against some typical toxic volatile organic vapors (VOCs), including Ethanol, Acetone, and Benzene at various sensor working temperatures at a fixed concentration for each vapor. From the calculated response magnitudes and response times, a data matrix was generated. A mathematical transformation method based on Principal Component Analysis (PCA) was then applied to evaluate the ability of combining a multisensing array based on ZnO and SnOx sensors operated at different temperatures to distinguish between the three target vapors according to their nature.
Structural and BET analysis XRD measurements were carried out with the aim to investigate the crystal structure of the annealed samples at 600°C. On one hand, the analysis obtained show that the prepared SnO x tubes are pure with an average grain size around 27. 13 nm and crystallize into a unique phase corresponding to the tetragonal rutile SnO x (fig. 6 a ), in accordance with the standard COD database values (code: 1521419). On the other hand, the analysis made on ZnO (fig. 6 b ) show that the prepared tubes are pure with an average grain size around 30. 87 nm and crystallize into the hexagonal phase, in agreement with the standard COD database values (code: 9004181). Furthermore, the results of BET analysis of N 2 adsorption isotherms depicted in figure  7  showed that the specific surface area of the MOs tubes was 38 m 2 /g and 71 m 2 /g for SnO x and ZnO respectively, which supported the high porosity observed by FESEM analysis in case of ZnO tubes (fig.
Conclusions In summary, pure and porous SnO x and ZnO ultrafine tubes were successfully prepared by a simple home-made Forcespinning system with diameters in the range of 0. 4-8 µm, as confirmed by FESEM, XRD, and EDS, TGA and BET analysis. The gas sensor response and response time for a variety of tested vapors were measured at different operating temperatures. The results demonstrated that the SnO 2 and ZnO sensor were sensitive to different toxic volatile organic vapors such as ethanol, acetone, and benzene with variable sensing response magnitude and kinetics. The data variability resulted in a discrimination of the three vapor patterns by combining the sensors based on both ZnO and SnO x , as observed in PCA scatter plots. All the above results proved the potential of the Forcespinning technology as a simple and scalable approach for preparing SnO x and ZnO ultrafine tubes for hazardous vapor monitoring.
The solid product separated from a mother liquid by decantation was dried and calcined at 600 • C for 2 h to obtain samples marked as Ce x Zr 1-x or Ni-Ce x Zr 1-x op. Along with one-pot NiCeZrO samples, Ni was supported on Ce-Zr oxides by a wet impregnation using an aqueous solution of Ni(NO 3 ) 2. The obtained catalysts dried and calcined at 600 • C were denoted as Ni-Ce x Zr 1-x im. XRD patterns of the samples were recorded on a D8 Advance diffractometer (Bruker, Germany) in the 2θ angle range of 20 -85 • using the CuKα radiation. The data were collected in a step-scanning mode with a step of 0. 05 • and a step-counting time of 3 s. In order to analyze the phase composition of complex oxides, the full-profile analysis was done using the software TOPAS (Bruker, Germany). At first, the lattice constants for each phase contained in the samples have been refined to determine the unit cell volume.
The chemical composition of the phases was evaluated from the literature data on the dependence of the cell volume versus the Ce content  [14, 15]. Then, we fixed the occupancies of Ce and Zr atoms in TOPAS to determine a weight ratio of two or three phases. The average particle sizes of nickel oxide were estimated by the Selyakov-Scherrer equation from the integral broadening of the most intensive (200) peak. Raman spectra were recorded on a LabRAM HR Evolution spectrometer (Horiba, Japan) in the backscattering configuration excited by 488 nm line of an Ar-ion laser. The texture of Ce x Zr 1-x O 2 or Ni-Ce x Zr 1-x op samples was studied by low-temperature N 2 adsorption technique using an ASAP-2400 instrument (Micromeritics, USA). Prior to analysis, the samples were degassed at 150 • C under vacuum for 16 h.
The charge correction was performed by setting the Ce3d 3/2 -u"' peak at 916. 7 eV. The samples were analyzed in the calcined and reduced state. After ex-situ reduction at 500 • C, they were transferred to the analysis chamber under an ambient atmosphere. The relative element concentrations were determined from the integral intensities of the core-level spectra using the cross-sections according to Scofield  [34]. For the detailed analysis, the spectra were fitted into several peaks after the background subtraction by the Shirley method. The fitted procedure was performed using the CasaXPS software. The reducibility of catalysts was studied by H 2 -temperature-programmed reduction (TPR). The sample (200 mg) was heated at a rate of 10 • C/min to 900 • C in an installation equipped with a thermal conductivity detector under a H 2 (10%)-Ar mixture with a flow of 40 mL/min.
Thus, for all one-pot catalysts, the hydrogen consumption below 300 • C is substantially larger. Meanwhile, the deconvoluted peaks corresponding to hydrogen consumption in the region of 300-700 • C are shifted to the higher temperatures (500 • C) as compared with impregnated ones (415-470 • C) (Figure  12 , Table  4 ). This indicates more difficult reduction of Ni 2+ in the one-pot catalysts that could be explained by stronger interaction of Ni with the supports due to a high NiO dispersion and Ni incorporation into the bulk of Ce-Zr-O solution as XPS data have shown. The correlation between the existence of Ni* state (Figure  10 ) and more pronounced low-temperature reduction in the case of one-pot catalysts (Table  4 ) could be because of Ce-Zr-O lattice distortion and generation of additional oxygen vacancies, due to Ni incorporation into the support structure.
Conclusions In the present work, we have realized a solvothermal continuous synthesis of Ce x Zr 1-x O 2 with the different Ce/Zr ratio as well as one-pot route for the preparation of Ni-modified Ce-Zr oxides. The admixtures of Ce-or Zr-enriched phases and the formation of Ce-Zr-O aggregates with Ce-enriched surface layer were observed for Ce x Zr 1-x O 2 with Ce/Zr ≥ 1. The Ce-Zr-O phase composition practically was not influenced by the addition of Ni and synthesis method of the catalysts, while the latter significantly affected NiO dispersion and its interaction with the support. The XRD and TEM data have shown that the one-pot synthesis of Ni-Ce-Zr-O catalysts leads to extremely small NiO nanoparticles/clusters (not observable by XRD), while clearly resolved ones (20-30 nm) are obtained for the impregnated catalysts.
Acoustic power measurements Acoustic power measurements were carried out by ultrasonicating 5 ml ultrapure water for 1 min. The temperature increase, due to the conversion of mechanical energy into heat, was recorded every second by using a National Instruments thermocouple controlled by a LabView software. For the acoustic power measurement in the absence of coupling fluid overpressure, the valve 1 and valve 2 were closed, and then the ultrapure water sonicated for 60 s. For sonication experiments involving an overpressure of the coupling fluid, at first the valve 2 was closed. Then the valve 1 was regulated by keeping the valve 3 open in such a way that the desired overpressure in the cooling jacket was obtained as soon as the valve 1 was fully closed. Then sonication was carried out for 1 min at the desired overpressure.
Acknowledgements Md. H. Islam and B. G. Pollet would like to thank the  ENERSENSE research initiative at NTNU  for the financial support to perform the experimental activities at the  UTINAM laboratories , the  University of Franche-Comté (UFC) ,  Besançon, France. They also thank the  UTINAM research team and the laboratory support  staff for their valuable support in carrying out the experiments.
The catalyst evaluation device is a four-channel methanation fixed bed reaction platform. The reaction temperature is mainly adjusted by a temperature controller (AI-518P) and syngas is measured and fed in through a mass flow controller (S49 33/MT). The water in the product is condensed by the condenser, and further dried to remove water through a drying column. The experimental data is monitored online by gas chromatography (SHIMADZU, GC 2014), detector is a thermal conductivity detector and the column model is TDX-01. Sampling interval is 30 min. The external standard method is used to calibrate the chromatography. The CO conversion and CH 4 selectivity calculation formula as fallow: X CO (%)=(V CO,in -V CO,out )/ V CO,in ×100% S CH4 (%)=V CH4,out /(V CO,in -V CO,out ) ×100% Catalytic activity of the catalysts was measured on a fixed bed microreactor.
Funding: The financial support of this project by the European Union Seventh Framework Programme FP7/2007-2013 under grant agreement number 608535 is gratefully acknowledged. The authors are also grateful for the financial support from the OT (11/061) funding from KU Leuven, the Belgian Federal Government through I. A. P. -P. A. I. grant (IAP 7/05 FS2), the Polish Ministry of Science and Higher Education through International Co-financed Project grant (2978/7. PR/2014/2) and the Erasmus Mundus fellowship funded by EACEA (EUDIME doctoral programme 4th edition).