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Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer-Emmett-Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro- and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already-measured raw adsorption isotherms were provided to sixty-one labs, who were asked to calculate the corresponding BET areas. This round-robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called ""BET surface identification"" (BETSI), expands on the well-known Rouquerol criteria and makes an unambiguous BET area assignment possible., European Union (EU); Horizon 2020; European Research Council (ERC); Research and Innovation Programme; NanoMOFdeli; COFLeaf; ERC-2016-COG; SCoTMOF; ERC-2015-StG; COSMOS; 2017-StG; European Commission (EC); H2020-MSCA-RISE-2019 Program; ZEOBIOCHEM; Innovate UK; EPSRC IAA; U.S. Department of Energy; Office of Basic Energy Sciences, Materials Sciences and Engineering Division; SERB; Spanish MICINN; AEI/FEDER; University of Alicante; Severo Ochoa Program; Spanish MINECO; Fund for Scientific Research Flanders (FWO); EPSRC Cambridge NanoDTC; National Research Foundation of Korea; Indonesian Endowment Fund for Education-LPDP;Cambridge International Scholarship; Trinity-Henry Barlow Scholarship (Honorary); U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy; Hydrogen and Fuel Cell Technologies Office; Hydrogen Storage Materials Advanced Research Consortium (HyMARC); Alexander von Humboldt Foundation; Center for Information Services and High Performance Computing (ZIH); Sandia National Laboratories; Official contribution of the National Institute of Standards and Technology (NIST)

Graphene Oxide (GO) is widely applied as an adsorbent for adsorption from solution. We show that GO undergoes transformation from micro to nanoscale and forms nanoscale GO (nanoGO) while it is subjected to adsorbed particular organic molecules. This phenomenon has been observed by the Dynamic Light Scattering (DLS), zeta potential, X-Ray Photoelectron Spectroscopy (XPS) and Fourier Transform Infrared (FTIR) measurements. A new model is proposed to take nanosizing into account. DFT calculations explain why some adsorbates can be captured from solution on GO and some are not adsorbed. This GO-nanoGO transformation is evidently supported by marked changes in the surface area of GO on liquid phase adsorption of organic molecules on different procedures.

Widespread peatland and wetland distribution is common in eastern Hokkaido, Japan. However, few studies of paleoenvironmental transition history in small alluvial lowland wetland systems located on the Konsen plateau have been conducted. A major obstacle is the reconstruction of a robust age model. Bulk radiocarbon dating, generally used for determining age of peat, must be employed with caution in selection of samples since peat and wetland sediments contain both plant remains at the time of sedimentation and various organic materials such as roots that are mixed from the layer above after sedimentation (Shinozaki, 2013). Radiocarbon dating on macrofossils and marker tephra provide accurate ages, but they cannot always be found from wetland sediments. On the other hand, pollen fossils show accurate radiocarbon dates (e.g. Brown et al., 1992). In this study, we measured radiocarbon from pollen fossils contained in a sediment core taken from a wetland of Chanai region on the Konsen Plateau, eastern Hokkaido, Japan. This study marks the first use of pollen to measure radiocarbon concentrations of peat by using flowcytometry, which allows for substantially more efficient pollen screening compared to conventional methods. To reconstruct paleoenvironments, we conducted high resolution elemental analysis on samples to interpret the origin of the wetland sediments and their decomposition rate. Tephra stratigraphic analysis of the core indicates that the transition to a wetland setting occurred between ca. 7.5-2.5 ka. Bulk radiocarbon dates suggest that the core sample preserved mostly continuous sediments from about 5.0 ka to the present. Results from elemental analysis showed that Total Organic Carbon (TOC) fluctuated between 20 and 40% at 90 to 60 cm below surface (cmbs), and between 40 and 50% at 40 to 5 cmbs, with a peak of 53% at 36 cmbs. The resulted carbon and nitrogen (C/N) ratios were about 14-20 between 90 and 40 cmbs, and were about 25 in the upper 40 cm of the

Isotopes of heavier gases including carbon (13C/14C), nitrogen (13N), and oxygen (18O) are highly important because they can be substituted for naturally occurring atoms without significantly perturbing the biochemical properties of the radiolabelled parent molecules. These labelled molecules are employed in clinical radiopharmaceuticals, in studies of brain disease and as imaging probes for advanced medical imaging techniques such as positron-emission tomography (PET). Established distillation-based isotope gas separation methods have a separation factor (S) below 1.05 and incur very high operating costs due to high energy consumption and long processing times, highlighting the need for new separation technologies. Here, we show a rapid and highly selective adsorption-based separation of 18O2 from 16O2 with S above 60 using nanoporous adsorbents operating near the boiling point of methane (112 K), which is accessible through cryogenic liquefied-natural-gas technology. A collective-nuclear-quantum effect difference between the ordered 18O2 and 16O2 molecular assemblies confined in subnanometer pores can explain the observed equilibrium separation and is applicable to other isotopic gases.