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Quantifying forest structural diversity based on large-scale inventory data:a new approach to support biodiversity monitoring

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forest Ecosystems 2018年第4期5卷 472-485页

作者： felix Storch carsten f.dormann Jurgen Bauhus Chair of Silviculture Tennenbacherstr 4University of FreiburgD-79085 FreiburgGermany Chair of Biometry Tennenbacherstr.4University of FrelburgD-79085FreiburgGermany

Background: The importance of structurally diverse forests for the conservation of biodiversity and provision of a wide range of ecosystem services has been widely recognised. However, tools to quantify structural diversity of forests in an objective and quantitative way across many forest types and sites are still needed, for example to support biodiversity monitoring. The existing approaches to quantify forest structural diversity are based on small geographical regions or single forest types, typically using only small data ***: Here we developed an index of structural diversity based on National forest Inventory(NfI) data of BadenWurttemberg, Germany, a state with 1.3 million ha of diverse forest types in different ownerships. Based on a literature review, 11 aspects of structural diversity were identified a priori as crucially important to describe structural diversity. An initial comprehensive list of 52 variables derived from National forest Inventory(NfI) data related to structural diversity was reduced by applying five selection criteria to arrive at one variable for each aspect of structural diversity. These variables comprise 1) quadratic mean diameter at breast height(DBH), 2) standard deviation of DBH, 3) standard deviation of stand height, 4) number of decay classes, 5) bark-diversity index, 6) trees with DBH ≥ 40 cm, 7) diversity of flowering and fructification, 8) average mean diameter of downed deadwood, 9) mean DBH of standing deadwood, 10) tree species richness and 11) tree species richness in the regeneration layer. These variables were combined into a simple,additive index to quantify the level of structural diversity, which assumes values between 0 and 1. We applied this index in an exemplary way to broad forest categories and ownerships to assess its feasibility to analyse structural diversity in large-scale forest ***: The forest structure index presented here can be derived in a similar way from standard inventor

关键词： Stand structure Structural diversity Structural diversity index Large-scale forest inventory Angle count sampling

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Chlorination of para-substituted phenols:formation of α, β-unsaturated C4-dialdehydes and C4-dicarboxylic acids

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Journal of Environmental Sciences 2022年第7期34卷 197-208页

作者： Zhuoyue Zhang carsten Prasse Department of Environmental Health and Engineering Johns Hopkins UniversityBaltimoreMD 21218USA

Despite the widespread occurrence of phenols in anthropogenic and natural compounds, their fate in reactions with hypochlorous acid(HOCl), one of the most common water treatment disinfectants, remains incompletely understood. To close this knowledge gap, this study investigated the formation of disinfection by-products(DBPs) in the reaction of free chlorine with seven para-substituted phenols. Based on the chemical structures of the DBPs and the reaction mechanisms leading to their formation, the DBPs were categorized into four groups: chlorophenols, coupling products, substituent reaction products, and ring cleavage products. In contrast to previous studies that investigated the formation of earlystage chlorophenols, the primary focus of this study was on the elucidation of novel ring cleavage products, in particular α, β-unsaturated C-dialdehydes, and C-dicarboxylic acids, which, for the first time, were identified and quantified in this study. The molar yields of 2-butene-1,4-dial(BDA), one of the identified α, β-unsaturated C-dialdehydes, varied among the different phenolic compounds, reaching a maximum value of 10.4% for bisphenol S. Molar yields of 2-chloromaleic acid(Cl-MA), one of the identified C-dicarboxylic acids, reached a maximum value of 30.5% for 4-hydroxy-phenylacetic acid under given conditions. 2,4,6-trichlorophenol(TCP) was shown to be an important intermediate of the parent phenols and the C-ring cleavage products. Based on the temporal trends of α, β-unsaturated C-dialdehydes and C-dicarboxylic acids, their formation is likely attributable to two separate ring cleavage pathways. Based on the obtained results, an overall transformation pathway for the reaction of para-substituted phenols with free chlorine leading to the formation of novel Cring cleavage products was proposed.

关键词： High-resolution mass spectrometry Ring cleavage products Quantification Transformation pathways Mass balance

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Performance characteristics of the airlift pump under vertical solid-water-gas flow conditions for conveying centimetric-sized coal particles

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International Journal of Coal Science & Technology 2024年第2期11卷 53-66页

作者： Parviz Enany carsten Drebenshtedt faculty of Mining and Special Civil Engineering Technische Universitat BergakademieGustav-Zeuner StraBe 1A09599FreibergGermany

In this study,the installation of an airlift pump with inner diameter of 102 mm and length of 5.64 m was utilized to consider the conveying process of non-spherical coal particles with density of 1340 kg/m3 and graining 25-44.5 *** test results revealed that the magnitude of increase in the solid transport rate due to the changes in the three tested parameters between compressed air velocity,submergence ratio,and feeding coal possibility was not the same,which are stand in range of 20%,75%,and 40%,***,creating the optimal airlift pump performance is highly dependent on submergence *** importantly,we measured the solid volume fraction using the method of one-way valves in order to minimize the disadvantages of conventional devices,such as fast speed camera and conductivity ring *** results confirmed that the volume fraction of the solid phase in the transfer process was always less than 12%.To validate present experimental data,the existing empirical correlations together with the theoretical equations related to the multiphase flow was *** overall agreement between the theory and experimental solid delivery results was particularly good instead of the first stage of conveying *** drawback can be corrected by omitting the role of friction and shear stress at low air income *** was also found that the model developed by Kalenik failed to predict the performance of our airlift operation in terms of the mass flow rate of the coal particles.

关键词： Vertical velocity Non-spherical particle Submergence ratio Three-phase flow Churn flow Superficial velocity

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HOW TO PROVE THE DISCRETE RELIABILITY fOR NONCONfORMING fINITE ELEMENT METHODS

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Journal of Computational Mathematics 2020年第1期38卷 142-175页

作者： carsten carstensen Sophie Puttkammer Department of Mathematics Humboldt-Universitat zu BerlinUnter den Linden 610099 BerlinGermany

Optimal convergence rates of adaptive finite element methods are well understood in terms of the axioms of *** key ingredient is the discrete reliability of a residualbased a posteriori error estimator,which controls the error of two discrete finite element solutions based on two nested *** the error analysis of nonconforming finite element methods,like the Crouzeix-Raviart or Morley finite element schemes,the difference of the piecewise derivatives of discontinuous approximations to the distributional gradients of global Sobolev functions plays a dominant role and is the object of this *** nonconforming interpolation operator,which comes natural with the definition of the aforementioned nonconforming finite element in the sense of Ciarlet,allows for stability and approximation properties that enable direct proofs of the reliability for the residual that monitors the equilibrium *** novel approach of this paper is the suggestion of a right-inverse of this interpolation operator in conforming piecewise polynomials to design a nonconforming approximation of a given coarse-grid approximation on a refined *** results of this paper allow for simple proofs of the discrete reliability in any space dimension and multiply connected domains on general shape-regular triangulations beyond newest-vertex bisection of *** attention is on optimal constants in some standard discrete estimates listed in the appendices.

关键词： Discrete reliability Nonconforming finite element method Conforming companion Morley Crouzeix-Raviart Explicit constants Axioms of adaptivity

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Assessing hydrological and provisioning ecosystem services in a case study in Western Central Brazil

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Ecological Processes 2014年第1期3卷 248-262页

作者： Lars Koschke carsten Lorz Christine fürst Tobias Lehmann franz Makeschin Department of Soil Science and Site Ecology Dresden University of TechnologyPienner Str.1901737 TharandtGermany faculty for Woods and forestry Forest PedologyGeology and Site EcologyHochschuleWeihenstephan-TriesdorfUniversity of Applied SciencesFreisingGermany Center for Development Research Department of Ecology and Natural Resources ManagementUniversity of BonnWalter-Flex-Str.353113 BonnGermany

Introduction:Current land use in the federal District,Western Central Brazil,causes problems related to the water supply which are linked to the regulation of ecosystem services(ES).In scope of an Integrated Water Resources Management concept,we further developed the web-based planning support tool GISCAME for the Pipiripau river basin case ***:We introduced analyses on ecosystem potentials in the raster-based tool to assess,in a spatially explicit manner,the scenario impact on water purification,sediment retention,water retention,and provision of food and fodder in order to identify potential pathways for conserving water *** demonstrate the method,we assess ES depending on a number of land use/land cover change(LULCC)***:We found that a considerable increase of water purification and sediment retention is difficult to achieve with realistic small scale LULCC,mainly because in areas with a low potential to provide hydrological ES and thus with a high demand for sustainable land use,such as native Savanna(Cerrado)and natural forests(Mata),favorable land uses were often already *** observed synergies in the response of regulating hydrological ES to LULCC but at the same time also trade-offs with provision of food and ***:Our findings suggest that further degradation and loss of Cerrado and Mata must be avoided and their restoration should be promoted in order to safeguard water *** suggest that restoration measures should be focused on arable land located at steep slopes near surface waters to effectively increase hydrological ES through the marginal reduction of provision services.

关键词： services retention provision

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Assessing geological uncertainty of a cement raw material deposit,southern Vietnam,based on hierarchical simulation

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International Journal of Mining Science and Technology 2020年第6期30卷 819-837页

作者： Trong Vu carsten Drebenstedt Tran Bao TU Bergakademie freiberg 09599 FreibergGermany Hanoi University of Mining and Geology Hanoi 10000Viet Nam

Resource modeling plays a crucial role in raw material quality management for cement *** has shown that geological uncertainty in resource modeling is inevitable and results in risk to future extraction planning and operations of the cement *** study aims to assess the geological uncertainty and associated risk in modeling a cement raw material deposit in southern *** this deposit,soil,clay,laterite,and limestone are the four primary rock types,controlling the occurrence and spatial distribution of chemical *** this study,hierarchical simulation method was used to evaluate the *** types were first simulated,and the chemical grades conditioning to the rock types were then *** results demonstrated the capability of the hierarchical simulation approach to incorporate the uncertainty of rock types in resource modeling and to allow evaluating the risks in providing the desired raw material for the cement plant in the form of grade-tonnage curves.

关键词： Cement raw material Geological uncertainty Rock types Grades Hierarchical simulation

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Preparation of hydrogels with uniform and gradient chemical structures using dialdehyde cellulose and diamine by aerating ammonia gas

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frontiers of Chemical Science and Engineering 2018年第3期12卷 383-389页

作者： Peiwen Liu carsten Mai Kai Zhang Wood Technology and Wood Chemistry Georg-August-Universitat Gottingen 37077 Gottingen Germany Wood Biology and Wood Products Georg-August-Universitat Gottingen 37077 Gottingen Germany

Hydrogels with precisely designed structures represent promising materials with a broad application spectrum, such as for sensor, tissue engineering and biomimetic technology. However, with highly reactive compounds, the preparation of hydrogels still needs an efficient approach for desired distribution of each component within hydrogels. In addition, a method for in situ preparation of gradient hydrogels is still lacking. Herein, we report the formation ofhydrogels with either uniform or gradient internal structures via a novel, simple but very efficient method by aerating ammonia gas （NH3 gas） into the solution of dialdehyde cellulose （DAC） and a diamine. As-prepared hydrogels exhibited uniform microscopic and chemical structure or gradient distribution Of functional groups. Due to lots of aldehyde groups on DAC chains, functional hydrogels can be prepared by using diverse diamines. for instance, hydrogels prepared by using 1,6-hexanediamine as a cross-linker were responsive to pH values. Moreover, this controllable process of aerating NH3 gas allows the in situ formation of gradient hydrogels; for instance, by using cyanamide as a reaction counterpart, gradient hydrogels with gradient distributions of cyanide groups were prepared.

关键词： hydrogel uniform gradient dialdehyde cellulose ammonia gas diamine

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Influence of secondary phases of AlSi9Cu3 alloy on the plasma electrolytic oxidation coating formation process

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Journal of Materials Science & Technology 2020年第15期47卷 75-85页

作者： Ting Wu carsten Blawert Mikhail LZheludkevich MagIC-Magnesium Innovation Centre Helmholtz-Zentrum Geesthacht21502 GeesthachtGermany Institute of Materials Science Faculty of EngineeringKiel UniversityKaiserstrasse 224143 KielGermany

To understand the formation and growth of plasma electrolytic oxidation(PEO) coatings in presence of different secondary phases in a substrate,PEO treatment was carried out on AlSi9 Cu3 alloy at different treatment times ranging from 15 s to 480 *** coating formation and evolution process was traced by surface and cross-sectional observation of the layers on the different phases of the *** results demonstrated a sequential involvement of the different phases in the plasma discharges:firstly,discharges start on the α-Al matrix,then on the intermetallic Al2 Cu and β-Al5 feSi phases at the same time and finally on the eutectic *** presence of intermetallic Al2 Cu remarkably affects the initial dissolution,the deposition of conversion products and the ignition of discharges at the early stages of *** Si in the substrate exhibits the highest electrochemical stability at all stages and contributes in the beginning to a distinct coating morphology *** resultant PEO coating tends to be uniform if processing times are longer and a double-layer structure appears in the coating.

关键词： Plasma electrolytic oxidation Aluminum alloy Secondary phases

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Regulation of natural killer cell activity by glucocorticoids,serotonin,dopamine,and epinephrine

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Cellular & Molecular Immunology 2020年第7期17卷 705-711页

作者： Silvia Capellino Maren Claus carsten Watzl Department for Immunology Leibniz Research Centre for Working Environment and Human Factors(IfADo)at TU DortmundDortmundGermany

The immune system and the nervous system are highly complex organs composed of various different cells that must interact with each other for proper function of the *** communication can be mediated by soluble *** factors released by the nervous system(neurotransmitters)differ from those released by the immune system(cytokines).Nevertheless,the nervous and immune systems can influence each other’s activity because immune cells express neurotransmitter receptors,and neurons express cytokine ***,immune cells can synthesize and release neurotransmitters themselves,thus using neurotransmittermediated pathways via autocrine and paracrine *** killer(NK)cells are innate lymphocytes that are important for early and effective immune reactions against infections and *** studies have shown the strong influence of stress and the nervous system on NK cell *** phenomenon may be one reason why chronic stress leads to a higher incidence of infections and ***,we review the effects of neuroendocrine factors on the different activities of NK *** the effects of neuroendocrine factors on NK cell activities during physiological and pathophysiological conditions may result in novel therapeutic strategies to enhance NK cell functions against tumors.

关键词： Natural Killer Cells Catecholamines Glucocorticoids Neurotransmitters

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Evaluation of airlift pump performance for vertical conveying of coal particles

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International Journal of Coal Science & Technology 2023年第3期10卷 155-166页

作者： Parviz Enany Oleksandr Shevchenko carsten Drebenshtedt faculty of Mining and Special Civil Engineering Technische Universitat BergakademieGustav-Zeuner StraBe 1A09599 FreibergGermany UTf GmbH ErzstraBe 1509618 Brand-ErbisdorfGermany

One of the crucial aspects of reducing air consumption when conveying particles with an airlift pump is to know the factors that affect the process of particle motion at an initial velocity of *** determine the influence of submer-gence ratio and physical properties of particles(such as size,shape,and mass)on the onset of vertical particle motion,the airlift pump was taken as the research object,and spherical glass together with irregular shaped coal were used as experimental test *** results show that unlike the water-solid environment,the start of particle motion in the water-air mixture does not always occur at a certain value of superficial water velocity and this value also increases with increasing submergence *** the parameters considered,the role of submergence ratio is much more effective than the dimensions and the shape of the particle,because by increasing submergence from 0.3 to 0.8,it is possible to reduce air consumption by up to 8 *** on this study the corresponding theoretical model derived by fujimoto et *** optimized,wherein the overall agreement between the modified theory and present experimental data is particularly *** to fujimoto,the minimum superficial water velocity for lifting solids in the air-water mixture is not always smaller than water ambient which indicates on optimum submergence ratio higher than ***,a new criterion was introduced to describe the moment of onset of the particle motion as a function of the superficial fluid velocity ratio for each submergence value.

关键词： Air-water-solid flow Slurry- Coal Submergence ratio Taylor bubble Superficial velocity

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