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Towards greener polymers:Trends in the German chemical industry

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Green Carbon 2024年第1期2卷 33-44页

作者： Adam W.Franz Stefan Buchholz rolf W.Albach rolf schmid BASF SE Ludwigshafen 67056Germany Evonik Operations GmbH Hanau 63457Germany Association for Chemistry and Economics German Chemical SocietyFrankfurt am Main 60444Germany Stuttgart University and Bio4Business Stuttgart 70569Germany

Global plastics production is expected to exceed 400 million tons and reach 600 million tons by *** synthesis currently accounts for approximately 3%of global greenhouse gas *** 60%of all polymers are produced for *** include shopping bags,packaging materials,mulch films,and soluble polymers for cosmetics and other ***,only a portion of single-use plastic is recycled or disposed of in incinerators or *** estimated 20%is not disposed of properly and pollutes the global environment,especially the *** response to these challenges,the United Nations,European Union,and many nation-states are developing regulatory frameworks that encourage the chemical industry to produce plastics with a smaller environmental footprint and often support this through research *** solutions include:(1)the use of green energy,green hydrogen,bio-based feedstocks,or CO_(2) in synthesis;(2)the reuse or recycling of plastics through conversion or pyrolysis;and(3)the production of biodegradable *** German chemical industry contributes approximately one-third of polymer production in the *** is embedded in the EU regulatory and research landscape and anchored in the European Green deal,which aims for carbon neutrality by *** this paper,we describe how BASF and Evonik,two leading German chemical companies with strong but different polymer portfolios,respond to the call for greener polymers and how technologies are being developed to make polyurethanes,a particularly important and difficult-to-recycle family of elastomers and duromers,renewable and *** the environmental footprint of plastics requires not only innovative materials but also proper governance,regulatory and collection systems,and public willingness to *** an international comparison of these competencies,expressed by the"polymer management index"(PMI),Germany achieved a top position.

关键词： Plastics recycling Biobased plastics Biodegradable plastics Polymer management index European Green deal

Functional dissimilarity in mixed forests promotes stem radial growth by mitigating tree water deficit

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National Science Review 2024年第3期11卷 55-57页

作者：张宏图艾尤尔.亥热提白云旻郭焱培李珊 Bernhard schmid Helge Bruelheide 马克平唐志尧 Institute of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of EducationPeking University College of Geography and Tourism Xinjiang Normal University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences department of Geography Remote Sensing LaboratoriesUniversity of Zurich Institute of Biology/Geobotany and Botanical Garden Martin Luther University Halle-Wittenberg German Centre for Integrative Biodiversity Research(idiv)Halle-Jena-Leipzig

Tree growth is a key component of forest ecosystem functioning and is wellknown to be limited by water availability[1]. It is acknowledged that composition and diversity of co-occurring tree species can mitigate the influence of drought on tree growth through the resource complementarity for water use via niche partitioning and facilitation between different species [2,3].

关键词： RESILIENCE

Meldonium-induced steatosis is associated with increased delta 6 desaturation and reduced elongation of n-6 polyunsaturated fatty acids

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Liver Research 2024年第3期8卷 152-164页

作者： Bodil Bjørndal Siri Lunde Tungland Pavol Bohov Magne OSydnes Simon N.dankel Lise Madsen rolf K Berge department of Clinical Science University of BergenBergenNorway department of Sports Physical Activity and FoodWestern Norway University of Applied SciencesBergenNorway department of Chemistry Bioscience and Environmental EngineeringUniversity of StavangerStavangerNorway department of Clinical Medicine University of BergenBergenNorway department of Heart disease Haukeland University HospitalBergenNorway

Background and objective Metabolic associated fatty liver disease(MAFLd)is associated with abnormal lipid *** dysfunction is considered an important factor in the onset of MAFLd,whereas altered fatty acid composition has been linked to the severity of the *** acid(TTA),shown to induce mitochondrial proliferation and alter the fatty acid composition,was used to delay the accumulation of hepatic *** study aimed to evaluate how impaired mitochondrial fatty acid beta-oxidation affects fatty acid composition by incorporating meldonium into a high-carbohydrate *** C57BL/6 mice(n=40)were fed high-carbohydrate diets supplemented with meldonium,TTA,or a combination of meldonium and TTA for 21 *** levels were determined in liver samples,and fatty acid composition was measured in both liver and plasma ***,desaturase and elongase activities were *** hepatic activities and gene expression levels of enzymes involved in fatty acid metabolism were measured in liver samples,whereas carnitines,their precursors,and acylcarnitines were measured in plasma *** The meldonium-induced depletion of L-carnitine and mitochondrial fatty acid oxidation was confirmed by reduced plasma levels of L-carnitine and *** component analyses of the hepatic fatty acid composition revealed clustering dependent on meldonium and *** meldonium-induced increase in hepatic triacylglycerol levels correlated negatively with estimated activities of elongases and was associated with higher estimated activities of delta-6 desaturase(d6d;C18:4n-3/C18:3n-3 and C18:3n-6/C18:2n-6),and increased circulating levels of C18:4n-3 and C18:3n-6(gamma-linolenic acid).TTA mitigated meldonium-induced triacylglycerol levels by 80%and attenuated the estimated d6d activities,and elongation of n-6 polyunsaturated fatty acids(PUFAs).TTA also attenuated the meldonium-mediated reduction of C24:1n-

关键词： Steatosis Fatty acid composition Fatty acid oxidation Meldonium desaturase Elongasen-6 polyunsaturated fatty acid

Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

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Open Journal of Soil Science 2024年第4期14卷 237-268页

作者： Neil-Yohan Musadji rolf Gaël Mabicka Obame Michel Mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire Claude Geffroy Laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France Laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Laboratoire Pluridisciplinaire des Sciences Ecole Normale Sup&#233rieure Libreville Gabon Centre de Recherche Sur La Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf Gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TdS) and minimum data set (MdS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TdS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/N ratio were retained in MdS, using principal component analysis (PCA). In the MdS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and NQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and NQI into the TdS and MdS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TdS and MdS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： Gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

distribution of debris Flows in Glacier National Park,Montana,U.S.A.

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Journal of Mountain Science 2008年第4期5卷 318-326页

作者： WILKERSON Forrest d. schmid Ginger L. department of Geography 7 Armstrong HallMinnesota State UniversityMankatoMN 56001USA

The spectacular scenery of Glacier National Park is the result of glacial erosion as well as post-glacial mass wasting processes. debris flow magnitude and frequency have been established through extensive fieldwork across seven separate drainage basins in the eastern portion of the park. This paper summarizes the investigation of the hypotheses that debris flow distribution in the Glacier National Park, east of the Continental divide is （a） not random; and Co） concentrated adjacent to the Continental divide. The location of 2317 debris flows were identified and mapped from sixty-three 1-m resolution digital Orthophoto Quarter Quadrangles and their spatial distribution was then analyzed using ArcView Spatial Analyst GIS software. The GIS analysis showed that the debris flows are not randomly distributed nor are they concentrated directly adjacent to the divide. While the Continental divide provides orographic enhancement of precipitation directly adjacent to the divide, the debris flows are not concentrated there due to a lack of available weathered regolith. The most recent Little Ice Age glaciation removed the debris directly adjacent to the divide, and without an adequate debris supply, these steep slopes experience few debris flows. Both abundant water and an adequate debris supply are necessary to initiate slope failure, resulting in a clustering of debris flows at the break in slope where valley walls contact talus slopes. A variety of summer storm and antecedent moisture conditions initiate slope failures in the Glacier National Park, with no distinct meteorological threshold. With over two million visitorsevery year, and millions of dollars of park infrastructure at risk, identifying the hazard of debris flows is essential to future park management plans.

关键词： debris flows remote sensing GIS GlacierNational Park USA

National Soil Organic Carbon Stocks Inventories under different Mangrove Forest Types in Gabon

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Open Journal of Forestry 2024年第2期14卷 127-140页

作者： rolf Gaël Mabicka Obame Neil-Yohan Musadji Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel Nzigou Boucka Michel Mbina Mounguengui Claude Geffroy dé partement de Phytotechnologie Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon dé partement des Sciences Fondamentales de l&#8217Ing&#233nieur Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut Agronomiques et Forestiè res Centre National des Recherches Scientifiques et Technologiques Libreville Gabon Research Centre on the durability and the Productivity of Industrial Plantations (CRdPI) Pointe Noire Republic of Congo Laboratoire Pluridisciplinaire des Sciences &#201cole Normale Sup&#233rieure Libreville Gabon Agence Gabonaise d’ &#201tude et d&#8217Observation Spatiale Immeuble les Arcades Libreville Gabon dé partement de G&#233ologie Faculte des Sciences Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux de Poitiers (IC2MP) Universit&#233 de Poitiers Poitiers France

Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in Gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha−1. Among the different regions, SOC in northern zone was significantly (p p deeper layers contained higher SOC stocks (254.62 ± 128.09 MgC ha−1) than upper layers (55.42 ± 25.37 MgC ha−1). The study highlights that low deforestation rate have led to less CO2 (705.3 Mg CO2e ha−1 - 922.62 Mg CO2e ha−1) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha−1) than primary (20.33 ± 12.7 MgC ha−1), savanna and cropland (21.71 ± 15.10 MgC ha−1). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data.

关键词： Mangroves Forest Soil Organic Carbon Stocks Rizophora Racemose Avicenia germinans Gabon

Transport and fate of mercury under different hydrologic regimes in polluted stream in mining area

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Journal of Environmental Sciences 2011年第5期23卷 757-764页

作者： Yan Lin Thorjorn Larssen rolf d. Vogt Xinbin Feng Hua Zhang department of Chemistry University of Oslo POB 1033 0315 Oslo Norway. E-mail:yan.lin@kjemi.uio.no Norwegian Institute for Water Research Gaustadalleen 21 0349 Oslo Norway State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Seepage from Hg mine wastes and calcines contains high concentrations of mercury （Hg）. Hg pollution is a major environmental problem in areas with abandoned mercury mines and retorting units. This study evaluates factors, especially the hydrological and sedimentary variables, governing temporal and spatial variation in levels and state of mercury in streams impacted by Hg contaminated runoff. Samples were taken during different flow regimes in the Wanshan Hg mining area in Guizhou Province, China. In its headwaters the sampled streams/rivers pass by several mine wastes and calcines with high concentration of Hg. Seepage causes serious Hg contamination to the downstream area. Concentrations of Hg in water samples showed significant seasonal variations. Periods of higher flow showed high concentrations of total Hg （THg） in water due to more particles being re-suspended and transported. The concentrations of major anions （e.g., Cl-, F-, NO3- and SO4^2-） were lower during higher flow due to dilution. due to both sedimentation of particles and dilution from tributaries the concentration of THg decreased from 2100 ng/L to background levels （〈 50 ng/L） within 10 km distance downstream. Sedimentation is the main reason for the fast decrease of the concentration, it accounts for 69% and 60% for higher flow and lower flow regimes respectively in the upper part of the stream. Speciation calculation of the dissolved Hg fraction （dHg）（using Visual MINTEQ） showed that Hg（OH）2 associated with dissolved organic matter is the main form of Hg in dissolved phase in surface waters in Wanshan （over 95%）.

关键词： mercury hydrology temporal variation fractionation and speciation

Application of Electron Beam Surface Technologies in the Automotive Industry

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材料热处理学报 2004年第5期25卷 573-578页

作者： rolf Zenker Anja Buchwalder TU Bergakademie Freiberg /Zenker Consult Mittweida GermanyTU Bergakademie Freiberg Germany

Progress in the beam deflection technique opens up new possibilities for the application of electron beam (EB) surface and welding technologies in the automotive industry. This development is based on three-dimensional high-speed beam deflection and fully automatic online process control. So, in the EB surface treatment three-dimensional energy transfer fields can be realised which take into account the contour of a component, the conditions of heat conduction and the load conditions. High flexibility, precision and reproducibility are typical characteristics. High productivity is achieved by the simultaneous interaction of the EB in several processing areas or by carrying out several processes simultaneously. EB surface treatment is becoming more and more attractive and important especially in the automotive industry, and also in comparison to laser technologies. This paper deals with different EB surface technologies, for example hardening, remelting, surface alloying, dispersing or cladding of different materials such as steel, cast iron and different alloys of Al, Mg and Ti. Examples of applications in the automotive industry, especially engine components, will be discussed.

关键词：电子注铸铁 3d射束偏移表面热处理

Trace metal concentrations in hairs of three bat species from an urbanized area in Germany

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Journal of Environmental Sciences 2015年第5期27卷 184-193页

作者： Lucie Flache Sezin Czarnecki rolf-Alexander düring Uwe Kierdorf Jorge A.Encarna??o Mammalian Ecology Group Department of Animal Ecology and Systematics Justus Liebig University Giessen Institute of Soil Science and Soil Conservation Justus Liebig University Giessen department of Biology University of Hildesheim

Metal-contaminated soils and sediments are widespread in urbanized areas due to atmospheric deposition close to emission sources. These metals are bio-available for organisms, e.g., insects, and accumulate in food chains of insectivorous *** bats, which live in urban regions and ingest large amounts of food relative to their body mass, are at risk of being poisoned due to the accumulation of trace metals. To determine species-specific trace metal contents in bats from urban environments, hair samples were analyzed by ICP-OES. Observed trace metal concentrations were related to species-specific foraging habitat, prey spectrum and degree of synanthropy. The species studied were Pipistrellus pipistrellus, Myotis daubentonii and Nyctalus noctula. P. pipistrellus showed the highest concentrations of lead and zinc and slightly higher concentrations of cadmium than the other two species, which was related to its high degree of synanthropy with foraging habitat mostly located in cities. In contrast, N. noctula displayed the highest contents of manganese and copper. The reason might be found in its prey spectrum, as N. noctula feeds mainly on beetles that are caught in cultured areas. Trace metal concentrations determined in hair samples of M. daubentonii ranged between the values of P. pipistrellus and N. noctula, probably reflecting an intermediate level of *** correlations were observed between the concentrations of cadmium and lead and those of manganese and copper. Hair samples from bats are suitable monitoring tools to study trace metal exposure and can be used to determine differences in trace metal levels between species.

关键词： Trace metals Urban bats Foraging habitat Prey spectrum Synanthropy ICP-OES