Carbon Trends最新文献

{"title":"New local pseudopotential for multilayer carbon materials and its application in wave packet dynamics","authors":"Géza I. Márk ,&nbsp;Péter Vancsó ,&nbsp;Alexandre Mayer","doi":"10.1016/j.cartre.2023.100310","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100310","url":null,"abstract":"<div><p>Formerly we created a one-electron local pseudopotential which proved to be successful in studying transport phenomena in various <em>sp²</em> carbon nanosystems, e.g. graphene grain boundaries and nanotube networks. In this work, we present an extended version of the local pseudopotential which correctly describes the electronic structure of van der Waals stacks of carbon sheets, e.g. AA, AB bi-layer graphene, ABC (rhombohedral) tri-layer graphene, as well as AA, AB, and ABC graphite, etc., even in case of external electric fields. We utilize this potential to study the hopping dynamics of wave packets between the graphene sheets in multilayer systems. The frequency of the hopping is proportional to the band splitting, caused by the interlayer coupling. For the case of AB and ABC graphene there is a backscattering near the Fermi level, causing a Zitterbewegung-like phenomenon, an interference between <span><math><mrow><mo>+</mo><msub><mi>k</mi><mrow><mi>B</mi><mi>l</mi><mi>o</mi><mi>c</mi><mi>h</mi></mrow></msub></mrow></math></span> and <span><math><mrow><mo>−</mo><msub><mi>k</mi><mrow><mi>B</mi><mi>l</mi><mi>o</mi><mi>c</mi><mi>h</mi></mrow></msub></mrow></math></span> states. For the rhombohedral tri-layer graphene the time dependence of the wave packet probability density is an aperiodic function for the first- and third layer (the two outer layers), but a quasi-periodic function for the second (inner) layer.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056923000652/pdfft?md5=6874627307f73eb992b0d36575cdc634&pid=1-s2.0-S2667056923000652-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92118080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence of natural fullerene C60 from the iridium-rich Cretaceous-Paleogene (K-Pg) boundary layers of the Um-Sohryngkew river section, Meghalaya, India","authors":"Bhaskar J. Saikia ,&nbsp;G. Parthasarathy ,&nbsp;Binoy K. Saikia ,&nbsp;Rashmi R. Borah","doi":"10.1016/j.cartre.2023.100309","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100309","url":null,"abstract":"<div><p>The presence of fullerene C₆₀ in the iridium-rich Cretaceous-Palaeogene (K-Pg) boundary layer from the Um-Sohryngkew river section of Meghalaya is reported here for the first time. Different analytical methods, including transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform infrared (FT-IR), and X-ray diffraction(XRD) techniques, have been used to characterize the presence of toluene-insoluble high-pressure phase of fullerene C₆₀ in the acid resistant carbonaceous matter extracted from the Um-Sohryngkew river section, Meghalaya, India. Strong absorption peaks at wavenumbers 1427, 1181, 574, and 525 cm⁻¹, which are indicative of pristine fullerene C₆₀, can be seen in the FTIR spectroscopic study. The Raman spectrum also independently confirms the presence of fullerene, by exhibiting the characteristics peaks of pristine fullerene C_60. The XRD technique provides further, independent validation of fullerenes, and the XRD pattern demonstrates fullerene presence. Fullerenes, high-pressure fullerene, the amorphous phase of C₆₀, and iridium all coexist and offer conclusive proof of impact at the Cretaceous-Palaeogene (K-Pg) boundary extinction event.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056923000640/pdfft?md5=d7d6ecccef83ef8c40286bf42cc1b29a&pid=1-s2.0-S2667056923000640-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91968650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Graphene nanosheets from the controlled explosion of aromatic hydrocarbons","authors":"Shusil Sigdel ,&nbsp;Justin P. Wright ,&nbsp;Jose Covarrubias ,&nbsp;Archana Sekar ,&nbsp;Kamalambika Mutthukumar ,&nbsp;Stefan H. Bossmann ,&nbsp;Jun Li ,&nbsp;Arjun Nepal ,&nbsp;Stephen Corkill ,&nbsp;Christopher M. Sorensen","doi":"10.1016/j.cartre.2023.100306","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100306","url":null,"abstract":"<div><p>Explosions of benzene, toluene and xylenes were carried out in a 16.7 L chamber in the presence of O₂ at different fuel-rich molar ratios such that an aerosol of elemental carbon was produced. The product was a powder at higher precursor oxygen content and an aerosol gel at lower oxygen where the carbon yield was larger. The explosion temperature was measured by a spectrometer that detected black body, Planck radiation from the incandescent carbon, the analysis of which indicated temperatures in the range 2000–2500 K. The product collected was characterized by Raman, X-ray diffraction, Brunauer, Emmett and Teller (BET) specific surface area, high-resolution transmission electron microscopy (HRTEM), etc. HRTEM and Raman showed two product types: amorphous soot at a lower explosion temperature and few-layer graphene at a higher explosion temperature. BET showed that the graphene sample is highly porous and has a specific surface area of 388 m²/g. We conclude that chamber explosion of aromatic hydrocarbons can produce graphene, and the high explosion temperature during the reaction is the primary reason graphene is formed rather than soot.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056923000615/pdfft?md5=7dafe8832ce91d0cae94265ae46534ba&pid=1-s2.0-S2667056923000615-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91968648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study on the applicability of non-stoichiometric thermodynamic models for the prediction of carbon black yield and off-gas composition in oil furnace process","authors":"Saeed Sahebdelfar ,&nbsp;Mohammad Soltanieh","doi":"10.1016/j.cartre.2023.100308","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100308","url":null,"abstract":"<div><p>The effect of feed composition and temperature on the carbon black yield and off-gas amount and composition was studied for oil-furnace process reactor with benzene as a model feedstock. Because of the high furnace temperature (&gt;1200 °C), the reactions were considered as very fast and thus the products close to chemical equilibrium. The equilibrium composition was calculated by a non-stoichiometric thermodynamic model using Gibbs free energy minimization method. The equilibrium and energy balance equations were solved simultaneously to obtain the product composition and reactor temperature under different reaction conditions. The equilibrium carbon black yield increases with gas/air and oil/air ratio whereas the reactor temperature exhibits the reverse trend which are consistent with practical data. Quantitative comparison with real data showed that the product may be kinetically controlled, and thus the thermodynamic model gives the lower limit of carbon black yield. The model can be easily applied to any feedstock including bio-oil without a need for the specific properties.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056923000639/pdfft?md5=a7e18f4bfb201bbdffd83dfcfc764beb&pid=1-s2.0-S2667056923000639-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91968649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cu-coated graphitic carbon nitride (Cu/CN) with ideal photocatalytic and antibacterial properties","authors":"Anu Kundu ,&nbsp;Dana Pousty ,&nbsp;Vinod Kumar Vadivel ,&nbsp;Hadas Mamane","doi":"10.1016/j.cartre.2023.100307","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100307","url":null,"abstract":"<div><p>An improved photocatalytic activity of Graphitic carbon nitride (CN) photocatalyst was achieved by incorporating Cu²⁺ into CN in the presence of hyperbranched polyethylene amine (HPEI) as a capping agent. The addition of Cu to CN (CN<img>HPEI+Cu) increased the photocatalytic degradation efficiency of wastewater dye pollutant methylene blue (MB) from 42 % to 95 %. <em>E. coli</em> and MS2 performed best in terms of inactivation to CN<img>HPEI+Cu, achieving 5.5 ± 0.3 and 5.3 ± 0.1 log inactivation after 60 min of exposure, respectively. Excellent catalyst reusability and photocatalytic activity for MB in various types were obtained. To investigate the photocatalyst structure, morphology, optical, and photoelectric properties, we used X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), and photocatalytic activity. It was found through XRD and XPS that the prepared photocatalysts were made up of Cu-doped CN and that the valence state of Cu was Cu⁰. Under the visible part of the solar spectrum (&gt;400 nm), the N₂ adsorption-desorption isotherms of pure CN, CN<img>HPEI, and CN<img>HPEI+Cu showed that copper did not alter the microstructure of pure CN. The photocatalytic activity of CN<img>HPEI+Cu was improved by incorporating Cu⁰ into CN, as this reduces the rate of electron-hole recombination in pure CN and accelerates the separation of electron-hole pairs. Electron spin resonance (ESR) spin trap experiments on the production of reactive oxygen species (ROS) from CN<img>HPEI+Cu under visible light indicate that the presence of superoxide radicals (O₂^•−), hydroxyl radicals (^•OH) and holes could enhance the photocatalytic activity of the material.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056923000627/pdfft?md5=7dc8cfef35fb0d47523a078488f91411&pid=1-s2.0-S2667056923000627-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92096488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Modeling of Kevlar/Jute Fiber and Hybrid Composite Pressure Vessels","authors":"Pranti Saha ,&nbsp;Md Foisal Hossain ,&nbsp;Muhammed Sohel Rana ,&nbsp;Md Shafiul Ferdous","doi":"10.1016/j.cartre.2023.100304","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100304","url":null,"abstract":"<div><p>In this study, nine composite overwrapped pressure vessel (<em>COPV)</em> models (type <em>IV</em>) have been developed to analyze their burst pressure performance using the ultimate tensile strength (<em>UTS)</em> from experiment and the von Mises stress profile from finite element ABAQUS simulation. The four-layer jute-reinforced <em>PV</em> shows almost five times lower burst pressure than Kevlar-based <em>PV</em>, indicating the inherent vulnerability of using pure jute. However, for the hybrid jute/Kevlar alternate combination, <em>JKJK</em> shows strength improvement over a jute <em>PV</em> by almost two times. Other jute hybrids with glass and aluminum foil show very comparable performance when compared to jute <em>PV</em>. Both yarn and braided-type jute fiber exhibit similar operating conditions, indicating that the preparation type of jute fiber is invariant to pressure performance. However, <em>COPVs</em> woven with 90° cross-oriented jute fibers are found to have the most degraded strength, highlighting that fiber orientation remains an important optimization factor in designing <em>PVs</em> with hybrid composite wraps.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49704236","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":"Optical, microstructural, and magnetic hyperthermia properties of green-synthesized Fe3O4/carbon dots nanocomposites utilizing Moringa oleifera extract and watermelon rinds","authors":"Adhistinka Jiananda ,&nbsp;Emi Kurnia Sari ,&nbsp;Dyah Ayu Larasati ,&nbsp;Rivaldo Marsel Tumbelaka ,&nbsp;Harlina Ardiyanti ,&nbsp;Mahardika Yoga Darmawan ,&nbsp;Nurul Imani Istiqomah ,&nbsp;Sunaryono ,&nbsp;Sigit Tri Wicaksono ,&nbsp;Edi Suharyadi","doi":"10.1016/j.cartre.2023.100305","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100305","url":null,"abstract":"<div><p>Cancer therapy with targeted-localized heating is one of the breakthroughs in the biomedical field. The incorporation of magnetic nanoparticles and fluorescent nanoparticles was one of the crucial issues for magnetic hyperthermia applications. This research investigates the magnetic hyperthermia properties of green-synthesized Fe₃O₄/CDs. Fe₃O₄ nanoparticles were synthesized using the coprecipitation method with Moringa oleifera leaf extract as a reducing agent and stabilizer. In contrast, CDs were synthesized using a hydrothermal method with watermelon rind waste as a carbon source. X-ray diffraction analysis confirmed the presence of cubic inverse spinel and a reduction in crystallite size with increasing CDs concentration. Transmission electron microscopy revealed particle size distributions of 9.7 nm for Fe₃O₄ and 7.5 nm for Fe₃O₄/CDs. Scanning electron microscopy showed that CDs were distributed on the surface of Fe₃O₄. The detection of characteristic Fe<img>O, C<img>C, C<img>O, and C<img>O-C bonds indicated the presence of CDs on the surface of Fe₃O₄. Ultraviolet-visible spectroscopy spectra absorption peaks at 282 nm for CDs and 193 nm for Fe₃O₄. Photoluminescence spectra indicated shifts from 509 to 505 nm in excitation wavelength for both CDs and Fe₃O₄/CDs, situated within the green region of visible light. The vibrating sample magnetometer revealed that the nanocomposites displayed characteristics of soft ferromagnetic materials. Furthermore, the specific absorption rate (SAR) value of Fe₃O₄/CDs was found to be dependent on magnetization. The SAR value of Fe₃O₄/CDs decreased as the concentration of CDs increased, and the frequency and strength of the AMF increased. Therefore, these results can promote Fe₃O₄/CDs nanocomposites as a promising candidate for magnetic hyperthermia applications.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2667056923000603/pdfft?md5=bd09a0c49c9da6859c828bf69a79ae53&pid=1-s2.0-S2667056923000603-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92096486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Defect-engineered graphene-on-silicon-carbide platform for magnetic field sensing at greatly elevated temperatures","authors":"Tymoteusz Ciuk ,&nbsp;Roman Kozłowski ,&nbsp;Agata Romanowska ,&nbsp;Andrzej Zagojski ,&nbsp;Karolina Piętak-Jurczak ,&nbsp;Beata Stańczyk ,&nbsp;Krystyna Przyborowska ,&nbsp;Dariusz Czołak ,&nbsp;Paweł Kamiński","doi":"10.1016/j.cartre.2023.100303","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100303","url":null,"abstract":"<div><p>High-temperature electrical properties of p-type hydrogen-intercalated quasi-free-standing epitaxial Chemical Vapor Deposition graphene on semi-insulating vanadium-compensated on-axis 6H-SiC(0001) and high-purity on-axis 4H-SiC(0001) originate from the double-carrier system of spontaneous-polarization-induced holes in graphene and thermally-activated electrons in the substrate. In this study, we pre-epitaxially modify SiC by implanting hydrogen (H⁺) and helium (He⁺) ions with energies ranging from 20 keV to 50 keV to reconstruct its post-epitaxial defect structure and suppress the thermally-developed electron channel. Through a combination of dark current measurements and High-Resolution Photo-Induced Transient Spectroscopy between 300 K and 700 K, we monitor the impact of ion bombardment on the transport properties of SiC and reveal activation energies of the individual deep-level defects. We find that the ion implantation has a negligible effect on 6H-SiC. Yet in 4H-SiC, it shifts the Fermi level from ∼600 meV to ∼800 meV below the minimum of the conduction band and reduces the electron concentration by two orders of magnitude. Specifically, it eliminates deep electron traps related to silicon vacancies in the charge state (2-/-) occupying the <em>h</em> and <em>k</em> sites of the 4H-SiC lattice. Finally, we directly implement the protocol of deep-level defect engineering in the technology of amorphous-aluminum-oxide-passivated Hall effect sensors and introduce a mature sensory platform with record-linear current-mode sensitivity of approximately 80 V/AT with -0.03-%/K stability in a broad temperature range between 300 K and 770 K, and likely far beyond 770 K.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49704235","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":"Mechanical energy absorption of architecturally interlocked petal-schwarzites","authors":"Leonardo V. Bastos ,&nbsp;Rushikesh S. Ambekar ,&nbsp;Chandra S. Tiwary ,&nbsp;Douglas S. Galvao ,&nbsp;Cristiano F. Woellner","doi":"10.1016/j.cartre.2023.100299","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100299","url":null,"abstract":"<div><p>We carried out fully atomistic reactive molecular dynamics simulations to study the mechanical behavior of six newly proposed hybrid schwarzite-based structures (interlocked petal-schwarzites). Schwarzites are carbon crystalline nanostructures with negative Gaussian curvature created by mapping a TPMS (Triply Periodic Minimal Surface) with carbon rings containing six to eight atoms. Our simulations have shown that petal-schwarzite structures can withstand uni-axial compressive stress up to the order of GPa and can be compressed past 50 percent strain without structural collapse. Our most resistant hierarchical structure has a calculated compressive strength of 260 GPa and specific energy absorption (SEA) of 45.95 MJ/kg, while possessing a mass density of only 685 kg/m³. These results show that these structures could be excellent lightweight materials for applications that require mechanical energy absorption.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49729547","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":"Biomass transformation towards diamondoids and beyond","authors":"Edward Furimsky","doi":"10.1016/j.cartre.2023.100298","DOIUrl":"https://doi.org/10.1016/j.cartre.2023.100298","url":null,"abstract":"<div><p>Adamantane (AD) is the first member in diamondoids family. It is an alkane of C₁₀H₁₆ formula, having a cage structure consisting of three fused cyclohexane rings. It was formed during biomass transformation towards crude oil, during final stages of catagenesis and on-set of metagenesis. It's appearance coincided with disappearance of biomarkers. Biomass origin of AD is indisputable although similar structures were not found in any type of biomass. Yet,precursors to AD arose from biomass.</p><p>The occurrence and survival of AD in crude oil was attributed to its high thermal stability. In reservoirs, biodegradation of ADs was noted. With progress of burial, cracking of AD left behind in source rock, aided by temperature, lythostatic pressure and acidic mineral matter, occurred. Graphite, rather than diamond was an ultimate product of the final AD transformation. Much higher temperatures and pressures are required for the conversion of AD to diamond than that to graphite.</p></div>","PeriodicalId":52629,"journal":{"name":"Carbon Trends","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49704390","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}