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17 pages, 14354 KiB

Open AccessArticle

Development of a Recycling Process for the Recovery of Gypsum Stone from Stockpile Material

by Jacob Fenner, Julius Luh, Bengi Yagmurlu and Daniel Goldmann

Recycling 2025, 10(1), 12; https://doi.org/10.3390/recycling10010012 - 16 Jan 2025

Viewed by 1567

Due to changes in the German government’s energy concept, the amount of gypsum produced in flue gas desulfurisation plants (FGD gypsum) will fall from 5 million tons per year to 1 million tons or less by 2038 at the latest. As of 2016, [...] Read more.

Due to changes in the German government’s energy concept, the amount of gypsum produced in flue gas desulfurisation plants (FGD gypsum) will fall from 5 million tons per year to 1 million tons or less by 2038 at the latest. As of 2016, FGD gypsum accounts for 55% of German gypsum mix. The resulting raw material gap must be closed through innovative recycling concepts, such as the processing of existing mine dumps. The process development aims to achieve a calcium sulfate dihydrate content of 85% and a reduction in the stockpile volume by 50%. The main components of the stockpiles are calcium sulfate in the form of gypsum stone as well as clay minerals and organic matter. Successful laboratory tests were transferred to a pilot scale jigging machine with dewatering screening. The process water is circulated throughout the entire process. The gypsum content in the heavy fraction is 76% when measured with ICP OES and 87% when measured via thermogravimetric methods. Furthermore, pilot-scale dry screening on the stockpile took place, and up to 1500 tons of material could be processed. Due to fluctuating weather conditions, the screening quality was subject to significant variations. Under optimal conditions, up to 60% of the feed could be recovered as gypsum stone; however, the screening process was nearly impossible during rain; therefore, a process combination of screening and a downstream jigging machine is recommended. Full article

(This article belongs to the Topic Sustainable Recycling and Reuse of Industrial By-Products or Waste from Geo-Resource Exploitation)

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12 pages, 1388 KiB

Open AccessCommunication

First Detection of Alphacoronavirus in Bats from the World’s Largest Wetland, the Pantanal, Brazil

by Tayane B. S. Magalhães, Amanda de O. Viana, Thiago B. F. Semedo, Juliane S. Saldanha, Nicole A. dos Reis, Nathalia de A. Pereira, Rachel V. P. de Barros, Hannah R. Miranda, Gabriella C. Almeida, Desyrée Y. S. R. Ozaki, Giovana S. Caleiro, Gustavo O. Fenner, Fernanda P. Vizu, Theo Kraiser, Thais P. Carvalho, Luciano M. Thomazelli, Erick G. Dorlass, Clarice W. Arns, Helena L. Ferreira, Erika Hingst-Zaher, Rogério Vieira Rossi, Guilherme S. T. Garbino, Edison L. Durigon, Jansen de Araujo and Daniel M. de Aguiar Show full author list Hide full author list

Pathogens 2025, 14(1), 58; https://doi.org/10.3390/pathogens14010058 - 11 Jan 2025

Viewed by 2732

Abstract

Coronaviruses (CoV) infect a wide variety of hosts, causing epidemics in humans, birds, and mammals over the years. Bats (order Chiroptera) are one of the natural hosts of the Coronaviridae family. They represent 40% of the total number of mammal species in the [...] Read more.

Coronaviruses (CoV) infect a wide variety of hosts, causing epidemics in humans, birds, and mammals over the years. Bats (order Chiroptera) are one of the natural hosts of the Coronaviridae family. They represent 40% of the total number of mammal species in the Pantanal, a biodiversity hotspot in South America. Given the recent SARS-CoV-2 pandemic, we investigated the presence of CoV in bats captured in the Brazilian Pantanal. Oral and rectal swabs collected in 2021 from 419 bats were analyzed using Pancoronavirus-nested PCR targeting the RNA-dependent RNA-polymerase (RdRp) gene. Orthocoronavirinae was detected in 16.7% (70/419) of the bats; nine samples were sequenced, confirming that Carollia perspicillata (4), Phyllostomus hastatus (2), Desmodus rotundus (1), Molossus rufus (1), and Myotis cf. nigricans (1) collected in buildings formally used by humans were infected by Alphacoronavirus genera. This is the first description of Alphacoronavirus in bats from the Pantanal. As they are natural reservoirs of CoVs, constant monitoring of bats is important to comprehend the epidemiology of emerging viruses, especially in the Pantanal biome. Full article

(This article belongs to the Section Viral Pathogens)

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8 pages, 2032 KiB

Open AccessProceeding Paper

Investigation of Industrial Residues and Waste Materials to Expand the Raw Material Base for the Production of Lightweight Aggregates

by Jacob Fenner, Andrej Zeller, Steffen Liebezeit, Manuela Knorr, Alexander Schnell, Luka Mettke and Daniel Goldmann

Mater. Proc. 2023, 15(1), 71; https://doi.org/10.3390/materproc2023015071 - 3 Jan 2024

Cited by 1 | Viewed by 920

Abstract

More than 218 million tonnes of mineral construction waste are produced in Germany every year. In view of the shortage of domestic raw materials and an increasing demand for lightweight aggregates and gypsum, it is important to find alternative sources of raw materials [...] Read more.

More than 218 million tonnes of mineral construction waste are produced in Germany every year. In view of the shortage of domestic raw materials and an increasing demand for lightweight aggregates and gypsum, it is important to find alternative sources of raw materials for the production of light aggregates. The main focus of our investigations is on construction and demolition waste and industrial by-products, which have so far only been used at a low level. Chemical analyses can be used to classify potential substances in the ternary diagram according to RILEY and to examine their basic suitability. However, the results show that the suitability of a raw material for the production of lightweight aggregates cannot be determined solely on the basis of the classification in the ternary diagram. Experimental investigations are necessary in any case. From the range of residual and waste materials investigated, the rhyolite fractions showed the best bloating properties. Without the addition of bloating agents, bloating values of 1.4 can be achieved. The addition of iron slurry to a reduction in the bloating temperature by about 100 °C, however, is associated with a slight reduction in the bloating value. With our investigations, we were able to show that an expansion of the raw material base for the production of lightweight aggregates is also possible beyond the use of classic, heterogeneous building rubble containing bricks. Full article

(This article belongs to the Proceedings of The 2nd International Conference on Raw Materials and Circular Economy “RawMat2023”)

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23 pages, 11075 KiB

Open AccessArticle

How Cool Are Allotment Gardens? A Case Study of Nocturnal Air Temperature Differences in Berlin, Germany

by Annemarie Tabea Rost, Victoria Liste, Corinna Seidel, Lea Matscheroth, Marco Otto, Fred Meier and Daniel Fenner

Atmosphere 2020, 11(5), 500; https://doi.org/10.3390/atmos11050500 - 13 May 2020

Cited by 27 | Viewed by 6672

Abstract

Urban green infrastructures have been extensively studied for their ability to mitigate the urban heat island (UHI) effect. However, allotment gardens (AGs)—a prominent type of urban green infrastructure within many European cities—have not yet been comprehensively investigated concerning their microclimates. In this study, [...] Read more.

Urban green infrastructures have been extensively studied for their ability to mitigate the urban heat island (UHI) effect. However, allotment gardens (AGs)—a prominent type of urban green infrastructure within many European cities—have not yet been comprehensively investigated concerning their microclimates. In this study, nocturnal air temperatures (

T_{N}

) in 13 AG complexes (AGCs) were measured during the summer of 2018 in Berlin, Germany. These were compared to measurements in densely built-up urban areas (URB), two large inner-city parks and rural areas (RUR). On average, the assessed AGCs were 2.7 K cooler at night than URB. Most of the investigated AGCs (11/13) displayed a larger mean

T_{N}

difference to URB (

\bar{Δ T_{N A G C}}

) than the examined urban parks. RUR showed the largest differences to URB (

\bar{Δ T_{N R U R}}

), indicating a UHI effect. Furthermore, the influence of land surface characteristics of the AGCs on

\bar{Δ T_{N A G C}}

was analyzed.

\bar{Δ T_{N A G C}}

decreased significantly as the floor space index around AGCs increased. The analysis of the shape complexity also produced a significant positive correlation with

\bar{Δ T_{N A G C}}

. In contrast, size and distance to the city center of an AGC decreased significantly with increasing

\bar{Δ T_{N A G C}}

. This study provides first insights into the microclimate of AGs and influencing variables concerning

T_{N}

. Full article

(This article belongs to the Section Climatology)

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17 pages, 3420 KiB

Open AccessArticle

Occurrence and Coupling of Heat and Ozone Events and Their Relation to Mortality Rates in Berlin, Germany, between 2000 and 2014

by Alexander Krug, Daniel Fenner, Achim Holtmann and Dieter Scherer

Atmosphere 2019, 10(6), 348; https://doi.org/10.3390/atmos10060348 - 25 Jun 2019

Cited by 16 | Viewed by 5222

Abstract

Episodes of hot weather and poor air quality pose significant consequences for public health. In this study, these episodes are addressed by applying the observational data of daily air temperature and ozone concentrations in an event-based risk assessment approach in order to detect [...] Read more.

Episodes of hot weather and poor air quality pose significant consequences for public health. In this study, these episodes are addressed by applying the observational data of daily air temperature and ozone concentrations in an event-based risk assessment approach in order to detect individual heat and ozone events, as well as events of their co-occurrence in Berlin, Germany, in the years 2000 to 2014. Various threshold values are explored so as to identify these events and to search for the appropriate regressions between the threshold exceedances and mortality rates. The events are further analyzed in terms of their event-specific mortality rates and their temporal occurrences. The results reveal that at least 40% of all heat events during the study period are accompanied by increased ozone concentrations in Berlin, particularly the most intense and longest heat events. While ozone events alone are only weakly associated with increased mortality rates, elevated ozone concentrations during heat events are found to amplify mortality rates. We conclude that elevated air temperatures during heat events are one major driver for increased mortality rates in Berlin, but simultaneously occurring elevated ozone concentrations act as an additional stressor, leading to an increased risk for the regional population. Full article

(This article belongs to the Section Biometeorology and Bioclimatology)

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16 pages, 6583 KiB

Open AccessArticle

The Human Influence Experiment (Part 2): Guidelines for Improved Mapping of Local Climate Zones Using a Supervised Classification

by Marie-leen Verdonck, Matthias Demuzere, Benjamin Bechtel, Christoph Beck, Oscar Brousse, Arjan Droste, Daniel Fenner, François Leconte and Frieke Van Coillie

Urban Sci. 2019, 3(1), 27; https://doi.org/10.3390/urbansci3010027 - 28 Feb 2019

Cited by 12 | Viewed by 4836

Abstract

Since 2012, Local Climate Zones (LCZ) have been used for numerous studies related to urban environment. In 2015, this use amplified because a method to map urban areas in LCZs was introduced by the World Urban Database and Access Portal Tools (WUDAPT). However [...] Read more.

Since 2012, Local Climate Zones (LCZ) have been used for numerous studies related to urban environment. In 2015, this use amplified because a method to map urban areas in LCZs was introduced by the World Urban Database and Access Portal Tools (WUDAPT). However in 2017, the first HUMan INfluence EXperiment showed that these maps often have poor or low quality. Since the maps are used in different applications such as urban modelling and land use/land cover change studies, it is of the utmost importance to improve mapping accuracies and a second experiment was launched. In HUMINEX 2.0, the focus lies on providing guidelines on the use of the mapping protocol based on the results of both HUMINEX 1.0 and 2.0. The results showed that: (1) it is important to follow the mapping protocol as strictly as possible, (2) a reasonable amount of time should be spent on the mapping procedure, (3) all users should perform a driving test, and (4) training area sets should be stored in the WUDAPT database for other users. Full article

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12 pages, 2289 KiB

Open AccessArticle

Nucleolar Expression and Chromosomal Associations in Robertsonian Spermatocytes of Mus musculus domesticus

by Fernanda López-Moncada, Daniel Tapia, Nolberto Zuñiga, Eliana Ayarza, Julio López-Fenner, Carlo Alberto Redi and Soledad Berríos

Genes 2019, 10(2), 120; https://doi.org/10.3390/genes10020120 - 6 Feb 2019

Cited by 2 | Viewed by 3694

Abstract

We studied and compared the nucleolar expression or nucleoli from specific bivalents in spermatocytes of the standard Mus musculus domesticus 2n = 40, of Robertsonian (Rb) homozygotes 2n = 24 and heterozygotes 2n = 32. We analyzed 200 nuclear microspreads of each specific [...] Read more.

We studied and compared the nucleolar expression or nucleoli from specific bivalents in spermatocytes of the standard Mus musculus domesticus 2n = 40, of Robertsonian (Rb) homozygotes 2n = 24 and heterozygotes 2n = 32. We analyzed 200 nuclear microspreads of each specific nucleolar chromosome and spermatocyte karyotype, using FISH to identify specific nucleolar bivalents, immunofluorescence for both fibrillarin of the nucleolus and the synaptonemal complex of the bivalents, and DAPI for heterochromatin. There was nucleolar expression in all the chromosomal conditions studied. By specific nucleolar bivalent, the quantitative relative nucleolar expression was higher in the bivalent 12 than in its derivatives, lower in the bivalent 15 than in its derivatives and higher in the bivalent 16 than its Rb derivatives. In the interactions between non-homologous chromosomal domains, the nucleolar bivalents were preferentially associated through pericentromeric heterochromatin with other bivalents of similar morphology and sometimes with other nucleolar bivalents. We suggest that the nucleolar expression in Rb nucleolar chromosomes is modified as a consequence of different localization of ribosomal genes (NOR) in the Rb chromosomes, its proximity to heterochromatin and its associations with chromosomes of the same morphology. Full article

(This article belongs to the Special Issue Male Germline Chromatin)

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22 pages, 15959 KiB

Open AccessArticle

Micro-Scale Variability of Air Temperature within a Local Climate Zone in Berlin, Germany, during Summer

by Justus A. Quanz, Susanne Ulrich, Daniel Fenner, Achim Holtmann and Jonas Eimermacher

Climate 2018, 6(1), 5; https://doi.org/10.3390/cli6010005 - 17 Jan 2018

Cited by 52 | Viewed by 10889

Abstract

The urban climate, especially the near-surface air temperature (

T

), is influenced to large amounts by urban surface properties on the local-scale. Landscape classification schemes, like the Local Climate Zone (LCZ) concept, classify neighbourhoods on this scale based on their surface properties, [...] Read more.

The urban climate, especially the near-surface air temperature (

T

), is influenced to large amounts by urban surface properties on the local-scale. Landscape classification schemes, like the Local Climate Zone (LCZ) concept, classify neighbourhoods on this scale based on their surface properties, neglecting sub-scale heterogeneity in the urban structure and its potential effects on

T

. To quantify sub-scale

T

variability, a measurement campaign with eleven stationary

T

sensors was conducted within one LCZ (class 2_B, compact midrise with scattered trees) in Berlin, Germany, during 22 days in summer 2016. Correlation analyses were performed between observed spatial

T

differences and micro-scale morphometric parameters around the measurement sites, such as sky view factor and building surface fraction. The results show mean night-time

T

differences of up to 1 K between the different sites. On a clear, calm and dry day, the daytime difference reached 3 K. At night-time, the variability can be best explained by the building surface fraction within a radius of 50 m. Further, a nocturnal cooling influence of a neighbouring green space could be observed. The observed micro-scale

T

variability was smaller than

T

differences to other LCZ classes, highlighting the applicability of the LCZ concept. Full article

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21 pages, 12519 KiB

Open AccessArticle

Quality of Crowdsourced Data on Urban Morphology—The Human Influence Experiment (HUMINEX)

by Benjamin Bechtel, Matthias Demuzere, Panagiotis Sismanidis, Daniel Fenner, Oscar Brousse, Christoph Beck, Frieke Van Coillie, Olaf Conrad, Iphigenia Keramitsoglou, Ariane Middel, Gerald Mills, Dev Niyogi, Marco Otto, Linda See and Marie-Leen Verdonck

Urban Sci. 2017, 1(2), 15; https://doi.org/10.3390/urbansci1020015 - 9 May 2017

Cited by 75 | Viewed by 13201

Abstract

The World Urban Database and Access Portal Tools (WUDAPT) is a community initiative to collect worldwide data on urban form (i.e., morphology, materials) and function (i.e., use and metabolism). This is achieved through crowdsourcing, which we define here as the collection of data [...] Read more.

The World Urban Database and Access Portal Tools (WUDAPT) is a community initiative to collect worldwide data on urban form (i.e., morphology, materials) and function (i.e., use and metabolism). This is achieved through crowdsourcing, which we define here as the collection of data by a bounded crowd, composed of students. In this process, training data for the classification of urban structures into Local Climate Zones (LCZ) are obtained, which are, like most volunteered geographic information initiatives, of unknown quality. In this study, we investigated the quality of 94 crowdsourced training datasets for ten cities, generated by 119 students from six universities. The results showed large discrepancies and the resulting LCZ maps were mostly of poor to moderate quality. This was due to general difficulties in the human interpretation of the (urban) landscape and in the understanding of the LCZ scheme. However, the quality of the LCZ maps improved with the number of training data revisions. As evidence for the wisdom of the crowd, improvements of up to 20% in overall accuracy were found when multiple training datasets were used together to create a single LCZ map. This improvement was greatest for small training datasets, saturating at about ten to fifteen sets. Full article

(This article belongs to the Special Issue Crowdsourcing Urban Data)

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