Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.043-046
A. Tkachev, N. Memetov, R. Stolyarov, N. Chapaksov, A. Gerasimova, V. Yagubov, A. Matveentsev, V. Bulgakova, S. Pozdnyakova
Nanocomposite materials based on a cold-cure silicone mixture containing multi-walled carbon nanotubes were obtained. The concentration dependences of the radio-physical properties of materials were investigated. An increase in the efficiency of shielding electromagnetic radiation in the radio frequency range of wavelengths with increasing concentrations of multi-walled carbon nanotubes up to 10 wt. % was verified.
{"title":"Electromagnetic Properties of Cold-Cure Silicone Mixtures Containing Multi-Walled Carbon Nanotubes","authors":"A. Tkachev, N. Memetov, R. Stolyarov, N. Chapaksov, A. Gerasimova, V. Yagubov, A. Matveentsev, V. Bulgakova, S. Pozdnyakova","doi":"10.17277/amt.2020.03.pp.043-046","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.043-046","url":null,"abstract":"Nanocomposite materials based on a cold-cure silicone mixture containing multi-walled carbon nanotubes were obtained. The concentration dependences of the radio-physical properties of materials were investigated. An increase in the efficiency of shielding electromagnetic radiation in the radio frequency range of wavelengths with increasing concentrations of multi-walled carbon nanotubes up to 10 wt. % was verified.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"38 1","pages":"043-046"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76497933","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.033-042
A. A. Zdanovich, M. Matsko, A. Melezhik, A. Tkachev, V. Zakharov
The data on the preparation of composite materials containing polyethylene and multi-walled carbon nanotubes (MWCNTs) of the Taunit brand are presented. To obtain these composites by in situ polymerization, a catalytic system formed by the interaction of an organomagnesium compound and TiCl4 on the surface of nanotubes was used. The catalyst fixed on the MWCNT surface has a high activity in ethylene polymerization and allows to obtain a polymer with different molecular weight. The data on the formation of a polymer on the MWCNT surface and the morphology of composites formed on various Taunit samples are presented.
{"title":"Preparation of Composite Materials Containing Polyethylene and Carbon Nanotubes by in situ Ethylene Polymerization over Titanium-Magnesium Catalyst Fixed on the Surface of Carbon Nanotubes","authors":"A. A. Zdanovich, M. Matsko, A. Melezhik, A. Tkachev, V. Zakharov","doi":"10.17277/amt.2020.03.pp.033-042","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.033-042","url":null,"abstract":"The data on the preparation of composite materials containing polyethylene and multi-walled carbon nanotubes (MWCNTs) of the Taunit brand are presented. To obtain these composites by in situ polymerization, a catalytic system formed by the interaction of an organomagnesium compound and TiCl4 on the surface of nanotubes was used. The catalyst fixed on the MWCNT surface has a high activity in ethylene polymerization and allows to obtain a polymer with different molecular weight. The data on the formation of a polymer on the MWCNT surface and the morphology of composites formed on various Taunit samples are presented.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"48 10","pages":"033-042"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91502445","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.008-017
P. Vityaz, V. Senyut, M. Kheifets, A. Kolmakov, S. Klimenko
Using modern ideas about the form of the phase diagram of boron nitride, the paper considers thermodynamic parameters and mechanisms of the synthesis of dense phases of boron nitride under equilibrium and nonequilibrium conditions. It has been verified that nanodiamonds, like fullerenes and carbon nanotubes, have catalytic properties and contribute to the solid-state conversion of graphite-like boron nitride to sphalerite modification at high pressures and temperatures. We propose a mechanism for the interaction of nanodiamond under high pressures with the surface of graphite-like boron nitride, which leads to a change in the type of electronic bond in its lattice from sp to sp with the formation of boron nitride with a wurtzite structure and its subsequent transformation into sphalerite boron nitride by the shear mechanism. The use of carbon-coated nanodiamonds resulted in an increase in the catalytically active centers of phase transformation in boron nitride in comparison with unmodified nanodiamonds, which was manifested in an increase in the content of sphalerite boron nitride in materials obtained under comparable technological synthesis conditions. Modified nanodiamonds also contribute to the intensification of the synthesis of superhard polycrystals as compared to uncoated nanodiamond additives, both due to the diffusion of carbon atoms along the grain boundaries of sphalerite boron nitride and due to the rearrangement of graphite microgroups into a diamond structure and sintering of the obtained diamond blocks with grains of sphalerite boron nitride. The process parameters of obtaining superhard polycrystals based on sphalerite boron nitride with the addition of detonation nanodiamond powders after chemical cleaning and surface modification with non-diamond forms of carbon were found.
{"title":"Synthesis of Superhard Materials Based on Sphalerite Boron Nitride Using Carbon Nanoparticles as a Phase Conversion Catalyst","authors":"P. Vityaz, V. Senyut, M. Kheifets, A. Kolmakov, S. Klimenko","doi":"10.17277/amt.2020.03.pp.008-017","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.008-017","url":null,"abstract":"Using modern ideas about the form of the phase diagram of boron nitride, the paper considers thermodynamic parameters and mechanisms of the synthesis of dense phases of boron nitride under equilibrium and nonequilibrium conditions. It has been verified that nanodiamonds, like fullerenes and carbon nanotubes, have catalytic properties and contribute to the solid-state conversion of graphite-like boron nitride to sphalerite modification at high pressures and temperatures. We propose a mechanism for the interaction of nanodiamond under high pressures with the surface of graphite-like boron nitride, which leads to a change in the type of electronic bond in its lattice from sp to sp with the formation of boron nitride with a wurtzite structure and its subsequent transformation into sphalerite boron nitride by the shear mechanism. The use of carbon-coated nanodiamonds resulted in an increase in the catalytically active centers of phase transformation in boron nitride in comparison with unmodified nanodiamonds, which was manifested in an increase in the content of sphalerite boron nitride in materials obtained under comparable technological synthesis conditions. Modified nanodiamonds also contribute to the intensification of the synthesis of superhard polycrystals as compared to uncoated nanodiamond additives, both due to the diffusion of carbon atoms along the grain boundaries of sphalerite boron nitride and due to the rearrangement of graphite microgroups into a diamond structure and sintering of the obtained diamond blocks with grains of sphalerite boron nitride. The process parameters of obtaining superhard polycrystals based on sphalerite boron nitride with the addition of detonation nanodiamond powders after chemical cleaning and surface modification with non-diamond forms of carbon were found.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"270 1","pages":"008-017"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76593287","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.018-027
A. G. Kolosko, V. S. Chernova, S. Filippov, E. O. Popov
A method for recording and emulating a complex experiment in field emission was developed. The method includes processing of three types of data streams: data on the electrical characteristics of the field cathode (voltage and current pulses), data on the field emission projector (glow patterns) and time-of-flight mass spectrometer data (mass spectra of volatile products in the measuring chamber). The LabView software environment implements an algorithm for synchronous reproduction of multichannel experiment data with the possibility of processing it in real time. The program has a built-in set of software tools that implement the functionality and repeat the experiment many times, pause at specified points in time, as well as change the time flow rate in the emulation. The capabilities of the method are demonstrated by the example of studying field emission from a nanocomposite field cathode based on carbon nanotubes.
{"title":"Method for Recording and Reproducing an Experimental Research into the Field Emitter Properties Based on Carbon Nanotubes","authors":"A. G. Kolosko, V. S. Chernova, S. Filippov, E. O. Popov","doi":"10.17277/amt.2020.03.pp.018-027","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.018-027","url":null,"abstract":"A method for recording and emulating a complex experiment in field emission was developed. The method includes processing of three types of data streams: data on the electrical characteristics of the field cathode (voltage and current pulses), data on the field emission projector (glow patterns) and time-of-flight mass spectrometer data (mass spectra of volatile products in the measuring chamber). The LabView software environment implements an algorithm for synchronous reproduction of multichannel experiment data with the possibility of processing it in real time. The program has a built-in set of software tools that implement the functionality and repeat the experiment many times, pause at specified points in time, as well as change the time flow rate in the emulation. The capabilities of the method are demonstrated by the example of studying field emission from a nanocomposite field cathode based on carbon nanotubes.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"3 1","pages":"018-027"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76929454","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.02.pp.033-039
A. V. Desyatov, Khimki Russia Global Co Llc, M. Chaika, V. V. Besedin, E. V. Bulavina, A. V. Denisenko, N. A. Shibanov
In this paper, we investigated the effect of the cathode material additive LiNi1/3Mn1/3Co1/3O2 (NMC111) on the capacity and specific energy of a hybrid lithium-ion supercapacitor (HLISC) with a positive electrode based on active carbon, a negative electrode based on graphite, and an auxiliary lithium electrode. The introduction of 35 % of the mass. NMC111 made it possible to increase the specific capacity of the storage device energy by ~ 77 % compared to a lithium-ion supercapacitor (LISC) with a cathode based on pure, non-doped active carbon. It was found that cycling at high current densities does not cause significant changes in the HLISC characteristics. This type of hybrid element proved to have two advantages. At low current densities, it exhibits charge-discharge properties of a lithium-ion battery with a high specific energy, and at high current densities, it exhibits the properties of a lithium-ion supercapacitor with a high specific power.
{"title":"Increasing of a Lithium-Ion Supercapacitor Specific Energy by Introducing LiNi1/3Mn1/3Co1/3O2 Additive into the Active Carbon-Based Cathode Material","authors":"A. V. Desyatov, Khimki Russia Global Co Llc, M. Chaika, V. V. Besedin, E. V. Bulavina, A. V. Denisenko, N. A. Shibanov","doi":"10.17277/amt.2020.02.pp.033-039","DOIUrl":"https://doi.org/10.17277/amt.2020.02.pp.033-039","url":null,"abstract":"In this paper, we investigated the effect of the cathode material additive LiNi1/3Mn1/3Co1/3O2 (NMC111) on the capacity and specific energy of a hybrid lithium-ion supercapacitor (HLISC) with a positive electrode based on active carbon, a negative electrode based on graphite, and an auxiliary lithium electrode. The introduction of 35 % of the mass. NMC111 made it possible to increase the specific capacity of the storage device energy by ~ 77 % compared to a lithium-ion supercapacitor (LISC) with a cathode based on pure, non-doped active carbon. It was found that cycling at high current densities does not cause significant changes in the HLISC characteristics. This type of hybrid element proved to have two advantages. At low current densities, it exhibits charge-discharge properties of a lithium-ion battery with a high specific energy, and at high current densities, it exhibits the properties of a lithium-ion supercapacitor with a high specific power.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"36 1","pages":"033-039"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75267521","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.03.pp.003-007
Y. Levinsky, M. M. Alymov, L. Rokhlin
The analysis of equilibrium in the Mg–Ni system was carried out. Alloys on its basis are promising for use as sorbents and hydrogen storage (START). The conditions for the production and operation of such alloys imply strict control of the pressure of hydrogen. In this regard, phase equilibria in the Mg–Ni system must be considered not only depending on the composition and temperature, but also on the pressure of hydrogen. The most complete graphical representation of the equilibrium in the Mg–Ni system is given by a three-dimensional state diagram: pressure-temperature-composition (p–T–x), the projection of the three-phase equilibrium lines of this diagram on the pressure-temperature plane (p–T-state diagram), isobaric and isothermal sections of the diagram, diagram in pMg–T coordinates. Based on the analysis of experimental data on equilibrium in this system, the article presents the most important options of the listed types of diagrams. The presented diagram variants can be useful in optimizing the technology and operation of sorbents and START alloys of the Mg–Ni system.
{"title":"The p–T–x-State Diagram of the Mg–Ni System","authors":"Y. Levinsky, M. M. Alymov, L. Rokhlin","doi":"10.17277/amt.2020.03.pp.003-007","DOIUrl":"https://doi.org/10.17277/amt.2020.03.pp.003-007","url":null,"abstract":"The analysis of equilibrium in the Mg–Ni system was carried out. Alloys on its basis are promising for use as sorbents and hydrogen storage (START). The conditions for the production and operation of such alloys imply strict control of the pressure of hydrogen. In this regard, phase equilibria in the Mg–Ni system must be considered not only depending on the composition and temperature, but also on the pressure of hydrogen. The most complete graphical representation of the equilibrium in the Mg–Ni system is given by a three-dimensional state diagram: pressure-temperature-composition (p–T–x), the projection of the three-phase equilibrium lines of this diagram on the pressure-temperature plane (p–T-state diagram), isobaric and isothermal sections of the diagram, diagram in pMg–T coordinates. Based on the analysis of experimental data on equilibrium in this system, the article presents the most important options of the listed types of diagrams. The presented diagram variants can be useful in optimizing the technology and operation of sorbents and START alloys of the Mg–Ni system.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"36 1","pages":"003-007"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75517759","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.04.pp.017-020
M. Markov, Y. Fadin, I. Kravchenko, A. Galinovsky, A. Belyakov, A. Bykova
The surface of metallic materials in friction pairs is protected from contact interaction by applying functional coatings. The minimum loads set in standard friction machines can be critical and instantly abrade the modified surface. Consequently, new promising approaches are needed in the development of coating diagnostics. This paper presents the approbation of a new promising method for evaluating thin-layer coatings based on the acoustic emission method using a reference sample.
{"title":"A Method for Determining Wear Resistance and Wear Depth of Thin-Layer Functional Coatings","authors":"M. Markov, Y. Fadin, I. Kravchenko, A. Galinovsky, A. Belyakov, A. Bykova","doi":"10.17277/amt.2020.04.pp.017-020","DOIUrl":"https://doi.org/10.17277/amt.2020.04.pp.017-020","url":null,"abstract":"The surface of metallic materials in friction pairs is protected from contact interaction by applying functional coatings. The minimum loads set in standard friction machines can be critical and instantly abrade the modified surface. Consequently, new promising approaches are needed in the development of coating diagnostics. This paper presents the approbation of a new promising method for evaluating thin-layer coatings based on the acoustic emission method using a reference sample.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"8 1","pages":"017-020"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75567470","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.04.pp.030-033
V. S. Trofimov, E. Petrov
Some sections of the theory of shock-wave processes in condensed media require substantial refinement. From a detailed analysis of the concept of heat of reaction, it follows that the three known heats of reaction characterize the same transformation of the reacting medium from three different sides. When considering the flows of a reacting medium, it is necessary to take into account turbulence and its changes as an analogue of thermal motion and physicochemical transformations of matter. Based on the analysis of the results of a unique experiment, it was concluded that the deformation of the condensed medium is a factor that determines the reaction rate along with temperature.
{"title":"Three Important Refinements of the Condensed Matter Detonation Theory","authors":"V. S. Trofimov, E. Petrov","doi":"10.17277/amt.2020.04.pp.030-033","DOIUrl":"https://doi.org/10.17277/amt.2020.04.pp.030-033","url":null,"abstract":"Some sections of the theory of shock-wave processes in condensed media require substantial refinement. From a detailed analysis of the concept of heat of reaction, it follows that the three known heats of reaction characterize the same transformation of the reacting medium from three different sides. When considering the flows of a reacting medium, it is necessary to take into account turbulence and its changes as an analogue of thermal motion and physicochemical transformations of matter. Based on the analysis of the results of a unique experiment, it was concluded that the deformation of the condensed medium is a factor that determines the reaction rate along with temperature.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"03 1","pages":"030-033"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78856277","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.04.pp.067-075
S. Al-Busaidi, S. V. Ponomarev
The article discusses an analytical model used in evaluation effectiveness and relative efficiency indicators of the processes performance in testing laboratories and a procedural model used to support manager in decision-making for implementing process improvement projects in the testing laboratories.
{"title":"Analytical and Procedural Decision-Making Models for Process Improvement Projects in Testing Laboratories","authors":"S. Al-Busaidi, S. V. Ponomarev","doi":"10.17277/amt.2020.04.pp.067-075","DOIUrl":"https://doi.org/10.17277/amt.2020.04.pp.067-075","url":null,"abstract":"The article discusses an analytical model used in evaluation effectiveness and relative efficiency indicators of the processes performance in testing laboratories and a procedural model used to support manager in decision-making for implementing process improvement projects in the testing laboratories.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"1 1","pages":"067-075"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90166939","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}
Pub Date : 2020-01-01DOI: 10.17277/amt.2020.04.pp.058-066
V. Buniatyan, H. Dashtoyan, A. Davtyan
In Part 2 of the paper, based on the results and assumptions pointed in Part 1, analytical expressions were derived for Schottky barrier thermal/field assisted and Poole-Frenkel emission currents. The computer modeling theoretical dependencies of the I–V characteristics has been compared with the experimental measured results and obtained good agreements.
{"title":"The I–V Characteristics of M–BaxSr1–xTiO3–M Thin Film Structures with Oxygen Vacancies. Part 2","authors":"V. Buniatyan, H. Dashtoyan, A. Davtyan","doi":"10.17277/amt.2020.04.pp.058-066","DOIUrl":"https://doi.org/10.17277/amt.2020.04.pp.058-066","url":null,"abstract":"In Part 2 of the paper, based on the results and assumptions pointed in Part 1, analytical expressions were derived for Schottky barrier thermal/field assisted and Poole-Frenkel emission currents. The computer modeling theoretical dependencies of the I–V characteristics has been compared with the experimental measured results and obtained good agreements.","PeriodicalId":13355,"journal":{"name":"Image Journal of Advanced Materials and Technologies","volume":"111 1","pages":"058-066"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82945727","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：