Industrial laboratory. Diagnostics of materials最新文献

{"title":"On the requirements for statistical methods of data analysis (generalizing article)","authors":"A. I. Orlov","doi":"10.26896/1028-6861-2023-89-11-98-106","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-98-106","url":null,"abstract":"Half a century activity in consulting researchers of various specialties, reviewing articles and books, opposing dissertations provided the possibility of getting acquainted with hundreds of specific studies on the development and application of statistical methods. A variety of shortcomings in conducting research and publishing the results of studies have been revealed, which hinder the perception of the data obtained, and in some cases cast doubt on the adequacy of the conclusions. Therefore, it appeared advisable to develop natural requirements for methods of data processing and presentation of the results of statistical data analysis. This study is devoted to an initial consideration of a number of formulations of such requirements. We proceed from the modern paradigm of applied statistics, based on non-parametric and non-numerical statistics which replace the primitive paradigm of the 19th century and the paradigm of the middle of the 20th century using parametric distribution systems. When describing and discussing the procedures for analyzing statistical data, it is necessary to start with probabilistic-statistical models for generating the data under study. It is necessary to proceed from the theory of measurements, according to which the first step in the data analysis is identification of the scales in which they are measured. Statistical inference must be invariant under the allowable transformations of data measurement scales. Since almost all distributions of real data are non-normal, a preference should be given to non-parametric formulations. The possibility of using parametric families of distributions must be carefully justified. In accordance with the theory of testing statistical hypothesis, both the null and alternative hypotheses must be specified. It is necessary to study the stability of the conclusions drawn from the model with respect to acceptable changes in the initial data and assumptions of the model. A number of further publications of the author will be devoted to the problems of developing a system of requirements for statistical models and methods.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139251997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the effect of the morphology of initial powders on the structural and dimensional characteristics of SiC-based porous ceramic materials","authors":"R. Kapustin, A. O. Kirillov, V. I. Uvarov, V. V. Zakorzhevsky","doi":"10.26896/1028-6861-2023-89-11-44-51","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-44-51","url":null,"abstract":"The realization of the necessary energy-efficient technological solutions for the production of highly porous SiC-ceramic materials requires appropriate research. The results of developing energy-efficient one-step methods for the synthesis of porous SiC-based ceramics and studying the characteristics of the obtained ceramics are presented. The effect of the morphology of initial powders on the synthesized product is considered. Ultrafine silicon carbide powders of two types, identical in characteristic particle size, but quite different in the surface morphology, were used as fillers in the synthesis of experimental samples of porous ceramics. The first one was obtained by the traditional furnace method (SiCf), the second one was synthesized by the technology of self-propagating high-temperature synthesis (SiCshs). It is shown that the particle morphology of initial powder components determines the structural parameters and characteristics of synthesized porous ceramics. The pore space parameters (average pore size, specific surface area, equivalent hydraulic diameter, permeability, etc.) can vary significantly. Porous ceramic materials synthesized on the basis of SiCf have an open porosity of 47%, high liquid permeability (up to 2 mDarcy), overwhelming dominance of α-SiC phase, and a narrow pore distribution with an average pore size of about 1 μm. High open porosity (more than 58 %), highly developed nanostructured pore space surface with an area of more than 12 m2/g, and wider pore size distribution (average pore size — 140 nm) are observed in porous ceramic materials based on SiCshs. The obtained results can be used to improve energy-efficient synthesis technologies and methods for predicting the properties of highly porous SiC-based ceramic materials. This will make it possible to create highly porous SiC ceramics within a priory predicted limits of effective applicability for the processes of ultrafiltration or catalysis.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139253375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modes of wear of babbitt-based composite materials produced by hot pressing","authors":"P. Bykov, I. Kalashnikov, L. Kobeleva, I. Katin, R. Mikheev","doi":"10.26896/1028-6861-2023-89-11-89-97","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-89-97","url":null,"abstract":"The effect of additives of Ti2NbAl intermetallic compound on the friction of B83 babbitt samples obtained by hot pressing was studied using optical, electron microscopy and EDS analysis. The structure, friction surface and wear products were studied. Tribological tests were carried out on a universal test system under conditions of dry sliding friction according to the scheme of axial loading: a steel bush against a disk of the material under study. The temperature values near the friction zone were recorded. The limits of application of the material depend on the mode and mechanism of wear occurring in the tribocontact. Changes in the mode and mechanism of wear were assessed by differences in the behavior of the friction coefficient, temperature, difference in the state of friction surfaces, wear intensity and wear products. The results obtained indicate the prospects of using the method of hot pressing of powder from the B83 alloy and discrete particles of the high-strength Ti2NbAl intermetallic phase to get composite materials with improved tribological properties compared to a babbitt alloy. The introduction of reinforcing high-modulus particles of intermetallic compounds changed the structure of the material and affected the friction processes in babbitt, pushing aside the onset of change in the mode of wear towards more severe friction conditions. A significant decrease in the wear intensity of babbitt-based composite materials compared to the original alloy makes it possible to predict an increase in the service life of tribo-units. The data obtained enable us to determine and recommend modes that improve the performance of tribo-nodes in the manufacture of both volumetric inserts and plain bearings made of B83 alloy and, moreover, to create new functionally organized layered compositions with enhanced tribotechnical properties with a base of structural steels and working surface layers not only using B83 babbitt, but also of composite materials based on B83 babbitt.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139253904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of cerium-substituted yttrium iron garnets by inductively coupled plasma atomic emission spectrometry with preliminary microwave decomposition","authors":"N. A. Korotkova, K. V. Petrova, V. B. Baranovskaya","doi":"10.26896/1028-6861-2023-89-11-24-33","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-24-33","url":null,"abstract":"An analytical procedure for inductively coupled plasma atomic emission (ICP-AES) analysis of iron garnets of the composition Y3 – xCexFe5 – yGayO12, where x = 0.4 – 0.5 and y = 2.4 – 2.6 with preliminary microwave decomposition of the sample is described. The compositions of acid mixtures (HCl/HNO3), as well as modes of microwave heating (holding time and temperature), providing complete dissolution of the samples are proposed. In addition to optimized sample preparation, conditions for ICP-AES analysis of cerium-doped yttrium iron garnets were studied. The effect of matrix components (Y, Ce, Fe, Ga) on the determination of doping elements was revealed and studied. The operating parameters of the spectrometer (ICP power and nebulizer flow rate) have been substantiated, which make it possible to reduce the matrix effect of Fe, Ga, Y, Ce on the elements Na, Mg, Al, Si, P, K, Ca, Sc, Cr, Mn, Co, Ni, Cu, Zn, Se, Cd, Sn, Te, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Pb in iron yttrium garnets by the ICP-AES. ICP-AES measurements were performed in the axial and radial mode for trace elements and in the radial mode for matrix elements. The limits of quantification (LOQs) of most elements ranged within n × 10–5 – n × 10–4 wt.%. The accuracy is confirmed by the spike recovery test. The relative standard deviation is in the range of 1 – 5% depending on the selected plasma view mode and the analyzed analytes. The developed method makes it possible to determine macro- and microcomponents in yttrium iron garnets in a wide range of concentrations with a high accuracy.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139252751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the phase characteristics of vibration sensors and conditions of orthogonalization of their measuring basis for the systems of vibration control and vibration testing of materials","authors":"A. Zhdanov","doi":"10.26896/1028-6861-2023-89-11-34-43","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-34-43","url":null,"abstract":"To identify the most vibration-sensitive structures of the materials during vibration tests, it is necessary to determine the vibration vector in an orthogonal basis The effectiveness of the tests depends on the accuracy of the vector measurement. The transverse sensitivity of tri-axial vibration transducers, which have found vast application in various vibration measuring and material testing systems, leads to increased measurement errors and limits the frequency range of measurements. The errors can be reduced to almost zero using the proposed method of electronic orthogonalization, which involves rotation of the sensitivity vectors until they coincide with the orthogonal basis, resulting in zero transverse sensitivity. This approach has been successfully developed and works rather well in the low frequency band of the vibration transducer frequency response, wherein the amplitude-characteristics are linear and there is no phase shift in the channels. An emphasis is made on the influence of the phase characteristics of vibration sensors on the formation of orthogonalizing matrices that determine the requirements for an orthogonalizer. The structure of the installation for automated recording amplitude-frequency and phase-frequency responses of the vibration transducer, methodology and results of experimental study of a tri-axial piezoelectric accelerometer (TPA) with one inertia element and oblique-angle measuring basis are presented. The results obtained under vibration activated in three mutually perpendicular directions along the measuring axes show that the transducer measuring system is properly designed to provide for effective broadband orthogonalization of the measuring basis. The results obtained can be used to develop orthogonalizing transducers that eliminate transverse sensitivity in a wide frequency range, as well as to improve the design of sensors and their metrological characteristics.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139251050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fields of residual stresses near open assemblage holes of aircraft wing panel","authors":"S. Eleonsky, M. D. Zaitsev, Y. G. Matvienko, V. Pisarev","doi":"10.26896/1028-6861-2023-89-11-71-88","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-71-88","url":null,"abstract":"The results of fatigue tests of two geometrically identical and similar in design models of the lower wing panel of a commercial aircraft are were analyzed. The panels differed in the way of installing mounting bolts, which connect the skin and stringers. Cold expansion of holes drilled both in the skin and stringer has been performed for the first panel before joining. The second panel includes no additional treatment after drilling pilot holes and final reaming. Bolts are mounted with an interference fit varying from 1.3 to 2.1% and from 2.9 to 3.2% for the first and the second panel, respectively. Changes in the interference fit are the consequence of a scatter attributed to the presence of a tolerance zone for the diameters of both bolts and mounting holes. A two-step comparison of both technologies is based on the experimental study of residual stress fields. The first stage, being a subject of the present study, includes the analysis of residual stress fields, which arise after removing bolts and separation of skin from stringers. Hole drilling and gradual crack growth were used to determine the components of residual stresses. Deformation response is measured by electronic speckle-pattern interferometry. High quality interferograms, which provide a reliable resolution of the interference fringes of ultimate density over the hole edge or directly along the notch borders, have been obtained for both ways of local removing the material. The first point-wise method based on drilling a probe hole, provides a quantitative determination of the residual stress components, starting from 1.4 mm distance from the assemblage hole edge. The second technique implements the crack compliance method of subsequent lengthening of the notch, starting directly from the mounting hole edge. This approach provides for a quantitative analysis of residual stress fields, related to different bolt mounting technologies, proceeding from the comparison of SIF values. A high level of compressive residual stresses near open holes is characteristic for both types of panels. Both experimental approaches showed the benefits of joints, where bolts are mounted into cold-expanded (reinforced) holes. For this case, the estimation of the relaxation parameters of the principal component of residual stresses in the direction of the external load is presented.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139252268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the electrophysical and magnetic properties of a Dirac 3D semimetal Cd3As2 with nanogranules of MnAs","authors":"L. A. Saypulaeva, N. Melnikova, M. M. Gadzhialiev, A. Tebenkov, A. Babushkin, V. Zakhvalinskii, M. H. Al-Onaizan, A. Ril","doi":"10.26896/1028-6861-2023-89-11-52-59","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-52-59","url":null,"abstract":"We report on the main results of studying the electrical and magnetoresistance (MR) of a composite material consisting of 70 % mol. Dirac semi-metal Cd3As2 and 30 % mol. ferromagnet MnAs at pressures up to 50 GPa in a diamond anvil cell with a «rounded cone-flat» type anvils, as well as magnetization at hydrostatic pressures up to 6 GPa in a toroid-shaped high-pressure cell, both at room temperature and in the temperature range of 180 – 350 K at atmospheric pressure. A mixture of methanol and ethanol in a ratio of 4:1 was used as a pressure transmitting medium. Elemental analysis of Cd3As2 + 30 % mol MnAs composites showed that much of the volume is occupied by the Cd3As2 phase. The proportion of MnAs phase inclusions is less than 5 %. The feature of Cd3As2 + MnAs is the presence of a significant region of non-mixing of the Cd3As2 and MnAs phase melts. A negative MR was revealed with increasing pressure in the entire studied baric zone. The maximum negative MR is observed in the baric zone of 22 – 26 GPa. Further increase in the pressure up to the maximum level result in the appearance of several extrema on the ΔR/R0(P) curve, with negative MR not exceeding 4 %. Upon pressure release from 50 GPa, the baric dependence of ΔR/R0(P) is characterized by an inversion of the MR sign: at pressures around 40 GPa, a negative MR is replaced by a positive MR, and at around 20 GPa, the maximum value of positive MR of ~5.3 % is observed. Signs of the instability of the monoclinic structure of Cd3As2 resulted from its partial decomposition upon decompression were revealed. The results obtained can be used in spintronics when using appropriate composite materials.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139253302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metrological assurance for the analytical control of flotation reagents based on aliphatic alkoxyamines in technological media and waste of iron ore enrichment processes","authors":"A. Y. Ivanova, I. B. Maksakova, V. A. Zirina, A. I. Krylov, N. A. Yurlova","doi":"10.26896/1028-6861-2023-89-11-14-23","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-14-23","url":null,"abstract":"Methodological developments related to the determination of the content of cationic flotation reagents (collectors) based on aliphatic alkoxyamines (Flotigam EDA, Tomamine M-4213, Feiying: TG-928) in technological media and waste of iron ore enrichment processes are considered to ensure the analytical control of technological processes in view of a danger character of generated waste. A spectrophotometric method for determination of cationic amino-containing surfactants can be used for express- and screening analysis. The method of gas chromatography was used to increase the reliability of alkoxyamine measurement and in arbitration cases. The ranges of determinable content for the photometric method in aqueous media were 0.04 – 100 mg/dm3 (extended uncertainty from 20 to 25%) and 3 – 1000 (extended uncertainty from 22 to 30%) in solid media; whereas for gas chromatographic procedure the content ranged within 0.02 – 100 mg/dm3 (extended uncertainty from 20 to 25%) in aqueous media and from 1.0 to 1000 mg/kg (extended uncertainty from 20 to 30%) in solid media, respectively. The methods for determination of the main components, alkoxyamines, in commercial compositions of amine-containing flotation reagents are also presented. The methods have been tested in modeling flotation procedures (to optimize relevant conditions and regimes of real production), certified and included in the Federal State Information System (FSIS) «Arshin».","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139253883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-target analysis of livestock products and feed for residues of drugs, pesticides, mycotoxins and their metabolites by high-resolution mass spectrometry (a review)","authors":"L. Kish, O. Lavrukhina, V. G. Amelin, A. Tretyakov, T. D. Pen’kov, D. Y. Nekrasov","doi":"10.26896/1028-6861-2023-89-11-5-13","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-5-13","url":null,"abstract":"A review of techniques of non-target analysis for simultaneous identification and determination of veterinary drugs, pesticides, mycotoxins, their metabolites, and substances of chemical transformation in livestock products using liquid chromatography and high-resolution mass spectrometry is presented. Some limitations of the approach are noted, such as the necessity of using common extraction conditions, the possibility of analyte transformations during the sample preparation, false positive results for isobaric and isomeric compounds, and the lack of spectral data for previously unexplored substances. However, the method is the most promising tool for the determination of pollutants not identified in the targeted analysis, as in the case of multicomponent screening of food and raw materials, and in the study of the parent compounds transformation.","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139252598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The use of acoustic emission in assessing the ductility loss in steel products under the effect of impact","authors":"N. Makhutov, I. E. Vasil’ev, D. Chernov, A. Marchenkov","doi":"10.26896/1028-6861-2023-89-11-60-70","DOIUrl":"https://doi.org/10.26896/1028-6861-2023-89-11-60-70","url":null,"abstract":"Acoustic emission (AE) diagnostics was carried out during tensile testing of 20KhN2MA steel samples to study the loss of ductility after the impact. We used V-notched samples (3.3 mm in depth) with overall dimensions of 300 × 20 × 6 mm. The impact in the concentrator zone caused the depletion of the plasticity of the material, which was accompanied by a decrease in the partial fraction of ductile fracture and an increase in brittle fracture. The test samples were divided into six batches. The samples of the first batch were not subjected to the impact. In the second batch, the impact energy was 50 J, in the third — 75 J, in the fourth — 100 J, in the fifth — 125 J and in the sixth — 150 J. The rupture tests were carried out at room temperature and at a speed of the movable traverse of 1 mm/min. The kinetics of damage in the notch zone during loading was monitored using the acoustic emission (AE) method and video recording. Processes of brittle and ductile (caused by cleavage and shear, respectively) destruction of the crystal lattice of a metal differ primarily in the speed and duration of stress waves. To separate AE pulses generated by these processes, spectrograms of time-frequency transformations and waveforms were analyzed. Pulse selection was carried out using a complex parameter reflecting the steepness of the amplitude drop at the phase of signal attenuation. Boundary values were determined that allow separation of the recorded pulses into flows caused by ductile and brittle structural damage to structural steels. It is shown that manifestation of the effect of impact on the exhaustion of the plastic properties of steel 20KhN2MA becomes noticeable when the level of specific work exceeds 50 J/cm2. Moreover, with an increase in the specific work up to 150 J/cm2, the weight content of location pulses characterizing the kinetics of brittle destruction of structural bonds increased by 3 – 4 times, relative to that recorded for the samples without impact. This result correlates with the duration of the rupture test of the samples, which was reduced by three times when the level of the specific work increased to 150 J/cm2","PeriodicalId":13559,"journal":{"name":"Industrial laboratory. Diagnostics of materials","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139252612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}