Article
Chemistry, Multidisciplinary
Antonio A. Castillo-Garcia, Christian Oliver Kappe, David Cantillo, Katalin Barta
Summary: In this study, an environmentally friendly method for extracting important phenolic chemicals from lignin was developed using electrochemical conversion and chemical functionalization steps. This method enables the transformation of lignocellulose into nitrogen-containing chemicals, such as aniline derivatives, to meet industrial demands.
Article
Chemistry, Analytical
Eko Setio Wibowo, Byung-Dae Park
Summary: This study investigates the relationship between structure and thermal degradation behavior of industrial softwood and hardwood kraft lignin (KL) after acetone fractionation. The results show that the acetone soluble (AS) fractions have lower molecular weight, less native wood lignin side chains, and more condensed structures. In contrast, the acetone insoluble (AI) fractions have higher molecular weight and more aliphatic hydroxyl groups and native lignin side chains.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2023)
Article
Environmental Sciences
Thao Thi Dao, Robert Mikutta, Leopold Sauheitl, Norman Gentsch, Olga Shibistova, Birgit Wild, Joerg Schnecker, Jiri Barta, Petr Capek, Antje Gittel, Nikolay Lashchinskiy, Tim Urich, Hana Santruckova, Andreas Richter, Georg Guggenberger
Summary: Permafrost thawing leads to decomposition of lignin and plant-derived sugars, with deeper active layers promoting a more pronounced decomposition trend. Future transformations of OM and carbon losses will also be modulated by mineralogical properties of soils.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2022)
Article
Engineering, Environmental
Wenting Zhou, Tian Ma, Xiufeng Yin, Xiaodong Wu, Quanlian Li, Dipesh Rupakheti, Xin Xiong, Qianggong Zhang, Cuicui Mu, Benjamin de Foy, Maheswar Rupakheti, Shichang Kang, Dahe Qin
Summary: Thaw slumps in permafrost regions can lead to significant carbon loss, but the contribution of microbial and plant-derived carbon in this process is not well understood. In a permafrost thaw slump in the Tibetan Plateau, the study provides direct evidence that microbial necromass carbon is a major component of the lost carbon. Microbial necromass carbon accounted for approximately 54% of the soil organic carbon loss in the thaw slump.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Soil Science
Lixiao Ma, Zhaoqiang Ju, Yunying Fang, Tony Vancov, Qiqi Gao, Di Wu, Aiping Zhang, Yanan Wang, Chunsheng Hu, Wenliang Wu, Zhangliu Du
Summary: Both nitrogen addition and warming have significant impacts on the molecular composition and sources of soil organic matter, especially in the surface soil; fungi are the main source of organic matter; warming can decrease the total free lipids content.
SOIL BIOLOGY & BIOCHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Antonio Ovejero-Perez, Victoria Rigual, Mercedes Oliet, Francisco Rodriguez, Juan Carlos Dominguez, M. Virginia Alonso
Summary: Biomass fractionation plays a crucial role in the development of competitive biorefineries, especially in the isolation and recovery of lignin. This study compared two fractionation processes, organosolv and ionosolv, using autohydrolyzed hemicellulose-free poplar as feedstock. The results showed that the ionosolv process at higher temperature achieved higher lignin recovery and produced more thermally stable lignin. The two processes had different effects on lignin recovery and properties.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2022)
Article
Agricultural Engineering
B. M. Majeke, F. -X. Collard, L. Tyhoda, J. F. Gorgens
Summary: The study found that the combined use of quinone reductase and lignin peroxidase can effectively reduce the molecular weight of lignin, limit the re-polymerization of lignin, and improve the degradation efficiency of lignin and the value of degradation products.
BIORESOURCE TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Jacob D. Zwilling, Xiao Jiang, Franklin Zambrano, Richard A. Venditti, Hasan Jameel, Orlin D. Velev, Orlando J. Rojas, Ronalds Gonzalez
Summary: Recent advances in developing sustainable, micro- and nanoscale materials from biobased resources have focused on utilizing lignin to strengthen the bioeconomy. However, there is a gap in the literature regarding the various interactions present during and after the formation of lignin micro- and nanoparticles (LPs). These interactions are influenced by the chemical composition, molecular weight distribution, and solvent/water polarity. Factors such as lignin concentration also play a role in nucleation and growth mechanisms, with LPs formed at low concentrations exhibiting larger particle sizes than those formed at higher concentrations.
Article
Biochemistry & Molecular Biology
Quan Zhang, Chenxing Dai, Jun Zhang, Xiaojun He, Xuesong Tan, Kai Zhang, Xia Xu, Xinshu Zhuang
Summary: Phenoxyethanol (EPH) was used to create a biphasic solvent system for lignin extraction from lignocellulosic biomass. The concentration of EPH was studied to determine the pre-treatment condition for lignin fractionation. The lignin from rice straw was then fractionated using a 70% aqueous EPH solvent system, resulting in the regeneration of lignin with varying purities using different precipitants. The compositional and structural characteristics of the regenerated lignin were also analyzed.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Environmental Sciences
Wen Sun, Tingjun Zhang, Gary D. Clow, Yan-Hua Sun, Wen -Yu Zhao, Ben -Ben Liang, Cheng-Yan Fan, Xiao-Qing Peng, Bin Cao
Summary: This study investigates permafrost changes and disappearance in the Qilian Mountains on the Tibetan Plateau, finding significant permafrost degradation with downward thawing rate of about 0.16 m per year, upward thawing rate of about 0.23 m per year, and lateral degradation rate of about -4.14 m per year. Results suggest that changes in climatic conditions may have limited impact on permafrost thawing, while moisture content and soil conditions play key roles.
ADVANCES IN CLIMATE CHANGE RESEARCH
(2022)
Article
Agricultural Engineering
Chenhuan Lai, Chundong Yang, Yuan Jia, Xin Xu, Kai Wang, Qiang Yong
Summary: This study investigates the relationship between lignin structures and their inhibitory effects in enzymatic saccharification. The results indicate that the content of condensed aromatic units and phenolic hydroxyl are crucial factors determining the lignin inhibition. The findings provide important insights for the development of lignocellulose biorefinery processes.
BIORESOURCE TECHNOLOGY
(2022)
Article
Multidisciplinary Sciences
Kristof Hegedus, Csaba Feher, Istvan Jalsovszky, Zoltan Kristof, Janos Rohonczy, Elemer Vass, Attila Farkas, Tamas Csizmadia, Gernot Friedbacher, Peter Hantz
Summary: The paper presents facile methods to obtain purified sporopollenin exine capsules and provides mass balances for classical and novel purification procedures. It is found that an ionic liquid, tetrabutyl phosphonium hydroxide, is the most effective in removing the intine wall. Various methods were used to investigate the sporopollenin capsules, revealing differences in O-aliphatic and aromatic constituents between sunflower and rape exines.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Multidisciplinary
Rui Liu, Annika Smeds, Luyao Wang, Andrey Pranovich, Jarl Hemming, Stefan Willfor, Hongbo Zhang, Chunlin Xu
Summary: This study established a novel method to isolate lignin fraction with decreased heterogeneity based on detailed characteristic examination of softwood Kraft lignin fractions. A practical and feasible three-step extraction process was proposed to separate the low heterogeneity lignin fraction from industrial lignin. Overall, this work presented a comprehensive study on the properties of softwood lignin and proposed a method to reduce the heterogeneity of lignin.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Agricultural Engineering
Hao Sun, Guanhua Wang, Jing Ge, Ni Wei, Wenjie Sui, Zicheng Chen, Hongyu Jia, Ashak Mahmud Parvez, Chuanling Si
Summary: This study focuses on the effect of lignin heterogeneity on the green synthesis of lignin nanosphere (LNS) supported Pd nanoparticles (Pd@LNS) and their catalytic performance. The results indicate that the use of low molecular weight lignin can significantly improve the catalytic performance of Pd@LNS.
INDUSTRIAL CROPS AND PRODUCTS
(2022)
Article
Energy & Fuels
Hong-Lei Yan, Xu Liu, Hai-Tao Wang, Zhan-Ku Li, Heng-Fu Shui, Zhi-Ping Lei, Shi-Biao Ren, Zhi-Cai Wang, Shi-Gang Kang
Summary: In this study, a highly dispersed and active NiRu/Al2O3 catalyst was prepared using layered double hydroxide for the hydrogenolysis of enzymatic hydrolysis lignin (EHL). The results showed that the strong interaction between Ni and Ru promoted the hydrogenolysis of lignin, leading to the production of more monomeric phenols. The soluble portion obtained under the optimal conditions had lower molecular masses and higher content of monomers/dimers.
Article
Environmental Sciences
Wangwang Ye, Yuhong Li, Jianwen Wen, Jiexia Zhang, Natalia Shakhova, Jian Liu, Man Wu, Igor Semiletov, Liyang Zhan
Summary: Increasing temperatures in the Arctic Ocean are causing changes in methane cycles, with methane being stored and transported from the Chukchi Sea to the central Arctic. The concentration of methane is increasing in the Upper Halocline, and its distribution is expanding due to intensified Pacific water inflow. Methane is also found in the Polar Mixed Layer and below-ice seawater in the basins, suggesting the influence of sea ice cycles and sediment-origin methane. The Arctic Ocean currently has minor atmospheric methane emissions, but the increasing methane excess and decreasing sea ice cover may lead to future emissions.
GLOBAL BIOGEOCHEMICAL CYCLES
(2023)
Article
Microbiology
Alexander S. Savvichev, Igor I. Rusanov, Vitaly V. Kadnikov, Alexey V. Beletsky, Elena E. Zakcharova, Olga S. Samylina, Pavel A. Sigalevich, Igor P. Semiletov, Nikolai V. Ravin, Nikolay V. Pimenov
Summary: Bottom sediments at methane discharge sites of the Laptev Sea shelf were investigated. The rates of microbial methanogenesis and methane oxidation were measured, and the communities responsible for these processes were analyzed. Methane content in the sediments varied from 0.9 to 37 mu mol CH4 dm(-3). Methane carbon isotopic composition (delta C-13-CH4) varied from -98.9 to -77.6 parts per thousand, indicating its biogenic origin. The rates of hydrogenotrophic methanogenesis were low (0.4-5.0 nmol dm(-3) day(-1)). Methane oxidation rates varied from 0.4 to 1.2 mu mol dm(-3) day(-1) at the seep stations. Four lineages of anaerobic methanotrophic archaea (ANME) (1, 2a-2b, 2c, and 3) were found in the deeper sediments at the seep stations along with sulfate-reducing Desulfobacteriota. The ANME-2a-2b clade was predominant among ANME. Aerobic ammonium-oxidizing Crenarchaeota (family Nitrosopumilaceae) predominated in the upper sediments along with heterotrophic Actinobacteriota and Bacteroidota, and methaneotrophs of the classes Alphaproteobacteria (Methyloceanibacter) and Gammaproteobacteria (families Methylophilaceae and Methylomonadaceae). Members of the genera Sulfurovum and Sulfurimonas occurred in the sediments of the seep stations. Methanotrophs of the classes Alphaproteobacteria (Methyloceanibacter) and Gammaproteobacteria (families Methylophilaceae and Methylomonadaceae) occurred in the sediments of all stations. The microbial community composition was similar to that of methane seep sediments from geographically remote areas of the global ocean.
Article
Engineering, Civil
Irina I. Pipko, Svetlana P. Pugach, Kseniia P. Shcherbakova, Igor P. Semiletov
Summary: Rivers play a crucial role in the carbon cycle in the Arctic. The study investigates the variations in dissolved organic carbon (DOC) concentrations and DOM composition in Siberian rivers and evaluates their relationship with carbonate chemistry. The findings provide valuable information for understanding the impact of climate change on biogeochemical cycles in the Arctic.
JOURNAL OF HYDROLOGY
(2023)
Article
Marine & Freshwater Biology
V. V. Malakhov, N. N. Rimskaya-Korsakova, A. A. Osadchiev, I. P. Semiletov, N. P. Karaseva, M. M. Gantsevich
Summary: This paper describes the discovery of new occurrences of pogonophores Siboglinum sp. and Nereilinum sp. from the St. Anna Trough in the Kara Sea. Previously, pogonophores were reported in the southern part of the Kara Sea. The presence of pogonophores in the St. Anna Trough indicates the presence of a methane flux associated with the inflow of Atlantic water, causing the dissociation of seafloor gas hydrates. The possible role of Arctic warming is apparent in both processes.
RUSSIAN JOURNAL OF MARINE BIOLOGY
(2023)
Review
Chemistry, Analytical
Artem A. Krylov, Roman A. Ananiev, Denis V. Chernykh, Dmitry A. Alekseev, Ermolay I. Balikhin, Nikolay N. Dmitrevsky, Mikhail A. Novikov, Elena A. Radiuk, Anna V. Domaniuk, Sergey A. Kovachev, Georgy K. Timashkevich, Vladimir N. Ivanov, Dmitry A. Ilinsky, Oleg Yu. Ganzha, Alexey Yu. Gunar, Pavel Yu. Pushkarev, Andrey V. Koshurnikov, Leopold I. Lobkovsky, Igor P. Semiletov
Summary: This article discusses the use of marine geophysical equipment in the Russian sector of the Arctic for detecting and studying areas with increased natural gas saturation. The equipment used includes high-frequency echo sounders, sub-bottom profilers, seismographs, and seismoacoustic profiling and electrical exploration equipment. The results obtained in the Laptev Sea show that these geophysical methods are effective in detecting and monitoring underwater gas release and studying the geological causes of gas emission.
Article
Environmental Sciences
Birgit Wild, Nicholas E. Ray, Celine Lett, Amelia Jane Davies, Elena Kirillova, Henry Holmstrand, Elizaveta Klevantceva, Alexander Osadchiev, Ivan Gangnus, Evgeniy Yakushev, Denis Kosmach, Oleg Dudarev, Orjan Gustafsson, Igor Semiletov, Volker Bruchert
Summary: This study focuses on the data-poor Arctic Ocean shelves north of Siberia, which are experiencing rapid warming and increasing nitrogen input due to permafrost thaw. The research finds that nitrogen concentrations in water column and sediments are elevated near large river mouths. N2O concentrations are weakly correlated with dissolved nitrogen and turbidity, indicating the influence of particulate matter from rivers and coastal erosion. The study suggests that N2O dynamics in the region are influenced by water column N2O consumption and production.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Environmental Sciences
Alexander Osadchiev, Zinaida Zabudkina, Vladimir Rogozhin, Dmitry Frey, Alexandra Gordey, Eduard Spivak, Anatoly Salyuk, Igor Semiletov, Roman Sedakov
Summary: The major Siberian rivers form large river plumes in the Arctic Ocean, which govern the structure of the sea surface layer. Little is known about the processes occurring within these river plumes in late autumn. In this study, in situ measurements were performed in the Kara Sea in late October, revealing intense convection and sharp salinity gradients in the Ob-Yenisei plume caused by cold air transport and horizontal mixing.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Lina Xie, Evgeniy Yakushev, Igor Semiletov, Andrey Grinko, Ivan Gangnus, Anfisa Berezina, Alexander Osadchiev, Igor Zhdanov, Alexander Polukhin, Julia Moiseeva, Darya Purgina, Irina Pipko, Svetlana Pugach, Oleg Dudarev, Zhenming Ge
Summary: Based on data collected from annual transects conducted from 2015-2020, this study explores the impact of River Lena plume dispersion on the hydrophysical and biogeochemical structure of the southeastern Laptev Sea. The results indicate that the spreading patterns of the plume play a crucial role in regulating local processes and show significant variation on both seasonal and interannual scales.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Engineering, Geological
Elena V. Gershelis, Alexey S. Ruban, Denis V. Chernykh, Natalina A. Poltavskaya, Igor P. Semiletov
Summary: Ongoing global warming leads to the accelerated release of organic carbon from permafrost to the Arctic shelf waters, which can be accumulated in sediments and undergo degradation and remineralization, resulting in significant environmental consequences. This study aims to assess the sources and degradation degree of terrigenous organic matter in the surface sediments of the Eastern Arctic seas. The hydrogen index values in modern marine sediments on the Eastern Arctic shelf are associated with the contribution of biolabile terrestrial organic matter, while other Arctic waters show a growing contribution of autochthonous organic matter. Moreover, there are significant deviations from the linear dependence in the d13C and HI/OI correlation, indicating a different geochemical regime in the Eastern Arctic seas.
BULLETIN OF THE TOMSK POLYTECHNIC UNIVERSITY-GEO ASSETS ENGINEERING
(2023)
Article
Geosciences, Multidisciplinary
Sergey Nikiforov, Roman Ananiev, Martin Jakobsson, Evgeny Moroz, Sergey Sokolov, Nikolay Sorokhtin, Nikolay Dmitrevsky, Elena Sukhikh, Igor Chickiryov, Yulia Zarayskaya, Anatoly Razumovskiy, Igor Semiletov
Summary: Based on data acquired during cruises of the RV Akademik Nikolaj Strakhov in 2018-2021, the distribution of submarine glacial landforms in the central part of the Pechora shelf area is revealed. The extent of the ice sheet during the Last Glacial Maximum (LGM) is proposed based on moraines and the distribution of glacial lineations. The mapped glacial landforms indicate the presence of an ice sheet in the area, while the Pechora basin was characterized by a cryogenic subaerial landscape.
Article
Geosciences, Multidisciplinary
Nickolay Sorokhtin, Nikolay Kozlov, Igor Semiletov, Leopold Lobkovsky, Sergey Nikiforov, Dmitry Alekseev, Roman Ananiev
Summary: Studies have shown that the Keivy domain of the Baltic Shield was tectonically overlapped by adjacent microcontinents during regional collision processes in the Late Archean, resulting in the submergence of the continental crust and the formation of a median massif. The Keivy massif entered the cratonization regime and experienced intense denudation processes and sedimentary cover accumulation. These processes occurred during the formation of the first supercontinent and the Early Precambrian glaciation, leading to the accumulation of extensive stratiform deposits of alumina raw materials within the Keivy median massif.
Article
Geosciences, Multidisciplinary
Dmitry A. Alekseev, Andrey V. Koshurnikov, Alexey Yu. Gunar, Ermolay I. Balikhin, Igor P. Semiletov, Natalia E. Shakhova, Nikolay A. Palshin, Leopold I. Lobkovsky
Summary: By using 1D numerical modeling and field data, the capabilities of the time-domain electromagnetic method (TDEM) for subsea permafrost mapping are analyzed. The effect of the background resistivity structure on the accuracy of inversion models is studied for settings typical for the East Siberian Arctic Shelf. Synthetic response analysis and regularized inversion are used to assess sensitivity and uncertainties in the geometry and resistivity of the reconstructed permafrost layer, confirming the efficacy of TDEM technology for subsea permafrost imaging.
Article
Geosciences, Multidisciplinary
Leopold I. Lobkovsky, Alexey A. Baranov, Igor A. Garagash, Mukamay M. Ramazanov, Irina S. Vladimirova, Yurii V. Gabsatarov, Dmitry A. Alekseev, Igor P. Semiletov
Summary: A correlation exists between changes in seismic activity and atmospheric methane concentration over the past 40 years. Deformation waves generated by large earthquakes near polar regions result in methane emission and glacier collapse. These waves can travel distances of 3000-4000 km and impact the Arctic and Antarctica several decades after the earthquakes occur.
Article
Environmental Sciences
Irina Pipko, Svetlana Pugach, Igor Semiletov, Oleg Konstantinov
Summary: This study assesses the dynamics of the seawater carbonate system, air-sea CO2 fluxes, and the corrosive waters in the East Siberian Sea. The eastern ESS is the main source of corrosive waters into the deep basin. This can potentially impact the ocean water ecosystem.
Article
Ecology
Dirk Jong, Lisa Broder, Tommaso Tesi, Kirsi H. Keskitalo, Nikita Zimov, Anna Davydova, Philip Pika, Negar Haghipour, Timothy I. Eglinton, Jorien E. Vonk
Summary: Arctic rivers are increasingly affected by thawing permafrost, and the fate of permafrost-derived organic carbon (OC) depends on complex processes along the source-to-sink system. A study on the Kolyma River and East Siberian Sea investigates the composition and degradation state of riverine OC compared to marine sediments. The results suggest that old permafrost-OC is mainly associated with sediments, while autochthonous primary production contributes to particulate OC.