52 research outputs found
Smart knowledge management driving green transformation: A comparative case study
Large energy companies and energy startups are increasingly focusing their resources to build new businesses concerning smart energy systems (SES). The development and integration of related innovative technologies for green transformation with traditional business models are often hampered, however, by the challenge of parallel management of exploitation of current business areas, and the exploration of new business areas with breakthrough innovation. While knowledge management could be key in this balancing strategy and shifting the organization to a more sustainable future, little is known about the challenges in the context of the energy sector. Applying a comparative case study method at a large energy company and a small energy startup, path dependency is reflected in KMS design in both cases, which could result in a slower shift to new technologies in case of the incumbent, and slower exploitation of the technological innovation in case of the startup. If a partnership is not an option for simulating structural ambidexterity, energy companies could speed up green transformation individually with smart knowledge management systems (SKMS) that support the development of contextual ambidexterity and SES
Biofuel supply chain planning and circular business model innovation at wastewater treatment plants : the case of biomethane production
Advanced biofuels, such as biomethane, could contribute to environmental sustainability in increasingly interrelated sectors, such as energy and waste management. Accordingly, innovative biomethane production technologies are argued to be the enablers of circular and waste-to-energy concepts, for example, at wastewater treatment plants (WWTPs). Nevertheless, their integration into biofuel supply chain (BSC) research is overlooked from a circular business model innovation (BMI) perspective. This study aims to address this research gap by focusing on an innovative biomethane production approach (power-to-gas, P2G) and related circular business model innovation opportunities in the context of WWTPs. We carried out lab-scale research and a case study at a mid-sized European WWTP to establish an empirical basis for large-scale techno-economic calculations. Despite the explored technological opportunity to increase advanced biofuel supply and decrease carbon dioxide emissions at WWTPs, current market risk levels challenge the economic prospects of the system concept. These empirical results demonstrate the necessity of policy interventions in different combinations (e.g., investment support, favourable taxation, feed-in tariffs). This study is one of the first to combine technological and business modelling aspects to support BSC planning, and supplement optimization-focused BSC research with explorative techno-economic analyses based on empirical data
Limnological changes and chironomid-inferred summer air temperature from the Late Pleniglacial to the Early Holocene in the East Carpathians
Here we provide the first chironomid record and associated summer air-temperature (T VII ) reconstruction between ca. 16,800-9100 cal yr BP from Lake Saint Anne (SZA), situated in the Eastern Carpathians. SZA was formed by the youngest volcanic eruption of Ciomadul volcano at ca. 29,600 cal yr BP. Our main goals in this study are to test whether warming after Heinrich event 1 (H1; ca. 16,200 cal yr BP) had similar amplitude to the late glacial warming, while Younger Dryas (YD) summers remained relatively warm in this region of Europe. We found the most remarkable chironomid assemblage change with a T VII increase of ~3.5-3.8°C at ca. 16,350 cal yr BP at SZA, followed by another slight T VII increase of ~0.8-1.0°C at ca. 14,450 cal yr BP. Only very minor temperature variations were recorded between 14,450 cal yr BP and 11,700 cal yr BP, with an unexpected T VII decrease in the Early Holocene. Variations in water depth together with increasing analogue problems and paludification from ca. 14,200 cal yr BP onwards may have influenced the reliability of our paleotemperature record obtained from SZA. In addition, Sphagnum -indicated decreasing pH, and hence decreasing nutrient level, likely overrode the effect of summer air-temperature changes during the Early Holocene, and this may explain the bias in the chironomid-inferred summer air-temperature reconstruction in the Early Holocene section
Radiocarbon chronology of glacial lake sediments in the Retezat Mts (South Carpathians, Romania): a window to Late Glacial and Holocene climatic and paleoenvironmental changes
Abstract
the Retezat Mountains, this study discusses radiocarbon chronology and sediment accumulation rate changes in two sediment profiles in relation to lithostratigraphy, organic content, biogenic silica and major pollenstratigraphic changes. A total of 25 radiocarbon dates were obtained from sediments of two lakes, Lake Brazi (TDB-1; 1740 m a.s.l.) and Lake Gales (Gales-3; 1990 m a.s.l.). Age-depth modeling was performed on TDB-1 using calibrated age ranges from BCal and various curve-fitting methods in psimpoll. Our results suggest that sediment accumulation began between 15,124–15,755 cal yr BP in both lakes and was continuous throughout the Late Glacial and Holocene. We demonstrated that local ecosystem productivity showed delayed response to Late Glacial and Early Holocene climatic changes in the subalpine and alpine zones most likely attributable to the cooling effect of remnant glaciers and meltwater input. However, regional vegetation response was without time lag and indicated forestation and warming at 14,450 and 11,550 cal yr BP, and cooling at ca. 12,800 cal yr BP. In the Holocene one major shift was detected, starting around 6300 cal yr BP and culminating around 5200 cal yr BP. The various proxies suggested summer cooling, shorter duration of the winter ice-cover season and/or increasing size of the water body, probably in response to increasing available moisture
Solvothermal synthesis of ZnO spheres: tuning the structure and morphology from nano- to micro-meter range and its impact on their photocatalytic activity
First record of Gomphonema lacunicola Patrick et Freese (Bacillariophyta) from the Pâreng Mts (Southern Carpathians, Romania)
Here we report and document the occurrence of the diatom Gomphonema lacunicola Patrick et Freese 1961 from the Pâreng Mts of the Carpathian Mountains, Romania. This observation was made within the framework of a systematic sampling campaign and analyses that were conducted in the Southern Carpathians, covering 40 mountain lakes for discovering the cladoceran fauna and diatom flora of this region between 2012 and 2014. G. lacunicola was found only in one of the 40 lakes, namely in Lake Câlcescu, where it was extremely rare, but the characteristic feature of the lake promoted the presence of the species. Lake Câlcescu is a subalpine lake, located 1,934 m a.s.l. This is the first record of this diatom species in Romania
Preparation and characterization of noble metal modified titanium dioxide hollow spheres – new insights concerning the light trapping efficiency
A neotektonika és a klímaváltozások szerepe a Körös medence késő-pleisztocén-holocén vízhálózatának fejlődésében = Neotectonic and climate control on Late Pleistocene-Holocene drainage pattern development of the Körös basin
A Körös-medence alluviális síkságának területén az egykori folyóhálózat nyomait rekonstruáltuk légifotó-elemzések, űrfelvételek, SRTM adatok és a folyószabályozás előtti természetes vízhálózatot mutató 18. századi topográfiai térképek alapján. Az elemzések azt mutatták, hogy a területen egy északkelet felől érkező nagy, meanderező folyó folyt, míg a déli részen egy fonatos folyó maradványai azonosíthatóak. A különböző mederrajzolatú zónákba 15 folyamatos magvételű sekélyfúrást mélyítettünk, illetve homok- és agyagfejtők szelvényeit is megvizsgáltuk. 32 homokminta optikai lumineszcens kormeghatározása (OSL), illetve 7 minta radiokarbon-vizsgálata alapján megállapítottuk, hogy a vizsgált folyóvízi üledékek a késő-pleniglaciális és a késő-glaciális során rakódtak le. A minták nehézásvány-vizsgálata alapján az egykori meanderező folyó az Ős-Tiszával azonosítható, amely az ÉK-DNy-i csapású Érmellék süllyedéke mentén folyt a késő-pleniglaciálisban. Az ős-Tisza érmelléki lefutását határon túli területek vizsgálata során 11 további OSL koradattal is alátámasztottuk. A fonatos folyó a Fekete- és Fehér-Körösök ősének tekinthető, amely csak a késő-glaciálisban jelent meg a területen. Szeizmikus szelvények újraértelmezése, neotektonikai terepi mérések, valamint a fúrásszelvényekben észlelhető eltérő vastagságviszonyok alapján az Érmellék vidéke 14-16 ezer évvel ezelőttig jelentős mértékben süllyedt, ami a folyófejlődés fő tektonikai meghatározója volt. | The palaeo-drainage network pattern of the Körös Basin was reconstructed on the basis of airborne photo interpretation, analysis of satellite images, SRTM dataset and historical topographic maps from the 18th century. The investigation showed that a large meandering river system was coming from the NE, and a braided river entered the alluvial plain from the SE. Different alluvial units were characterised by sedimentary logs of 15 continuous cored boreholes and several sand- and clay-pit sections. OSL dating of 32 quartz samples and 7 radocarbon datings showed that the sediments have Late Pleniglacial to Late Glacial ages. Transport directions inferred from heavy mineral analyses demonstrate that the large meandering river system can be identified with the palaeo-Tisza, flowing along the NE-SW striking Érmellék depression during the Late Pleniglacial. The former flow path of the palaeo-Tisza was supported by complementary field work performed in Romania, and another 11 OSL dates. The braided river can be regarded as a precursor to the Fekete- and Fehér-Körös rivers which entered the alluvial plain from the southeast during the Late Glacial. A combined interpretation of seismic profiles, neotectonic field measurements and variations in thickness of sediments along the studied profile revealed that there was a remarkable tectonic control on river development, driven by subsidence along the Érmellék depression until 14-16 ky and uplift of the SE-ern part of the catchment area
Social Context of Late Medieval and Early Modern Deforestation Periods in the Apuseni Mountains (Romania) based on an Integrated Evaluation of Historical and Paleobotanical Records
CRYPTIC 2021: The Imprint of Climate and the Human Activity in the Diatom Communities of Lowland and Mountain Lakes in the Carpathians = Cryptic 2021: A klíma és az emberi tevékenység lenyomata tavaink kovaalga-közösségeiben a Kárpátokban
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