Recent progress in melt pyrolysis:Fabrication and applications of high-value carbon materials from abundant sources

The escalating demand for sophisticated carbon products,including carbon black,carbon nanotubes(CNTs),and graphene,has yet to be adequately addressed by conventional techniques with respect to large-scale,efficient,and controllable carbon material synthesis.Molten pyrolysis emerges as a propitious strategy for generating such high-value carbonmaterials.Abundant carbon sources encompassing methane(CH_(4)),carbon dioxide(CO_(2)),biomass,and plastics can undergo thermal decomposition into carbon constituents within molten metal or salt media.This methodology not only obviates dependence on traditional fossil fuels but additionally enables modulation of carbon material morphologies by varying the molten media,thereby presenting substantial potential for effective and controlled carbon material fabrication.In this review,we examine the capacity of molten pyrolysis in producing high-value carbon materials derived from CH_(4),CO_(2),biomass,and plastics.Concurrently,we present a detailed overview of the potential applications of this novel methodology,particularly emphasizing its relevance in the fields of supercapacitors,flexible materials,and electrochemical cells.Furthermore,we contemplate future trajectories for molten pyrolysis,accentuating that amalgamation with auxiliary processes or technologies—like renewable energy systems and carbon capture and storage—represents a remarkably promising route for continued investigation.

Community structure of picoplankton abundance and biomass in the southern Huanghai Sea during the spring and autumn of 2006

During spring and autumn of 2006, the investigations on abundance, carbon biomass and distri- bution of picoplankton were carried out in the southern Huanghai Sea （Yellow Sea, sHS）. Three groups of picoplankton-Synechococcus （Syn）, Picoeukaryotes （PEuk） and heterotrophic bacteria （BAC） were identified, but Prochlorococcus （Pro） was undetected. The average abundance of Syn and PEuk was lower in spring （5.0 and 1.3×10^3 cells/cm^3, respectively） than in autumn （92.4 and 2.7×0^3 cells/cm^3, respectively）, but it was opposite for BAC （1.3 and 0.7×10^6 cells/cm^3 in spring and autumn, respectively）. And the total carbon biomass of picoplankton was higher in spring （37.23×11.67） mg/m^3 than in autumn （21.29×13.75） mg/m^3. The ratios of the three cell abundance were 5：1：1 341 and 30：1：124 in spring and autumn, respectively. And the ratios of carbon biomass of them were 5：7：362 and 9：4：4 in spring and autumn, respectively. Seasonal distribution characteristics of Syn, PEuk, BAC were quite different from each other. In spring, Syn abundance decreased in turn in the central waters （where phytoplankton bloom in spring occurred）, the southern waters and inshore waters of the Shandong Peninsula （where even Syn was undetected）; the high values of PEuk abundance appeared in the central and southern waters and the inshore of the Shandong Peninsula; the abundance of BAC was nearly three order of magnitude higher than that of photosynthetic picoplankton, and high values appeared in the central waters. In autumn, Syn abundance in central waters was higher than that in surrounding waters, while for PEuk abundance, it decreased in turn in the inshore waters of the Shandong Peninsula, the southern waters and the central waters; BAC presented a complicated blocky type distribution. Sub-surface maximum of each group of picopalnkton appeared in both spring and autumn. Compared with the available lit- eratures concerning the studied area, the range of Syn abundance was larger, and the abundance of BAC was higher. In addition, the conversion factors for calculating picoplanktonic carbon biomass were discussed, with the conversion factors which are different from previous studies in the same surveyed waters. The result of regression analysis showed that there was distinct positive correlation between BAC and photosynthetic picoplankton in spring （r=0.61, P 〈0.001）, but no correlation was found in autumn.

Effects of long-term nitrogen addition on theδ^(15)N andδ^(13)C of Larix gmelinii and soil in a boreal forest

Background:Natural abundance of carbon(C)and nitrogen(N)stable isotope ratios(δ^(13)C andδ^(15)N)has been used to indicate the state and cycle of ecosystem C and N.However,it is still unclear how C and N cycle of boreal forests respond to the N deposition.Results:We conducted an 8-year continuous N addition field experiment in a Larix gmelinii forest in Greater Khingan Mountains,Northeast China.Four N treatments(0,25,50,75 kg N ha^(−1)year^(−1))were built.The effects of N addition on theδ^(13)C andδ^(15)N of needle,branch,bark,and fine root of Larix gmelinii and soil were studied.The result of the balance between the N input and output flux showed that N addition significantly increased theδ^(15)N in each organ of Larix gmelinii,but did not change theδ^(15)N of soil.We also found that the N absorption by needles of Larix gmelinii could increase the needle photosynthesis rate andδ^(13)C by increasing carboxylation,but N addition had no significant effect on theδ^(13)C of soil and other organs.In addition,both the soilδ^(15)N andδ^(13)C increased with the soil depth.Conclusions:Long-term N addition may lead to more open C and N cycles and further affect plant nutrient acquisition strategies in boreal forest ecosystems.