---
_id: '59510'
abstract:
- lang: eng
text: The use of organo-catalysis in continuous-flow reactor systems is
gaining attention in medicinal chemistry due to its cost-effectiveness and reduced
chemical waste. In this study, bioactive curcumin (CUM) derivatives were synthesized
in a continuously operated microfluidic reactor (MFR), using piperidine-based
polymeric networks as catalysts. Piperidine methacrylate and piperidine acrylate
were synthesized and subsequently copolymerized with complementary monomers (MMA
or DMAA) and crosslinkers (EGDMA or MBAM) via photopolymerization, yielding different
polymeric networks. Initially, batch reactions were optimized for the organo-catalytic
Knoevenagel condensation between CUM and 4-nitrobenzaldehyde, under various conditions,
in the presence of polymer networks. Conversion was assessed using offline 1H
NMR spectroscopy, revealing an increase in conversion with enhanced swelling properties
of the polymer networks, which facilitated greater accessibility of catalytic
sites. In continuous-flow MFR experiments, optimized polymer gel dots exhibited
superior catalytic performance, achieving a conversion of up to 72%, compared
to other compositions. This improvement was attributed to the enhanced swelling
in the reaction mixture (DMSO/methanol, 7:3 v/v) at 40 °C over 72 h. Furthermore,
the MFR system enabled the efficient synthesis of a series of CUM derivatives,
demonstrating significantly higher conversion rates than traditional batch reactions.
Notably, while batch reactions required 90% catalyst loading in the gel, the MFR
system achieved a comparable or superior performance with only 50% catalyst, resulting
in a higher turnover number. These findings underscore the advantages of continuous-flow
organo-catalysis in enhancing catalytic efficiency and sustainability in organic
synthesis.
article_number: '278'
author:
- first_name: Naresh
full_name: Killi, Naresh
last_name: Killi
- first_name: Katja
full_name: Rumpke, Katja
last_name: Rumpke
- first_name: Dirk
full_name: Kuckling, Dirk
id: '287'
last_name: Kuckling
citation:
ama: Killi N, Rumpke K, Kuckling D. Synthesis of Curcumin Derivatives via Knoevenagel
Reaction Within a Continuously Driven Microfluidic Reactor Using Polymeric Networks
Containing Piperidine as a Catalyst. Gels. 2025;11(4). doi:10.3390/gels11040278
apa: Killi, N., Rumpke, K., & Kuckling, D. (2025). Synthesis of Curcumin Derivatives
via Knoevenagel Reaction Within a Continuously Driven Microfluidic Reactor Using
Polymeric Networks Containing Piperidine as a Catalyst. Gels, 11(4),
Article 278. https://doi.org/10.3390/gels11040278
bibtex: '@article{Killi_Rumpke_Kuckling_2025, title={Synthesis of Curcumin Derivatives
via Knoevenagel Reaction Within a Continuously Driven Microfluidic Reactor Using
Polymeric Networks Containing Piperidine as a Catalyst}, volume={11}, DOI={10.3390/gels11040278}, number={4278},
journal={Gels}, publisher={MDPI AG}, author={Killi, Naresh and Rumpke, Katja and
Kuckling, Dirk}, year={2025} }'
chicago: Killi, Naresh, Katja Rumpke, and Dirk Kuckling. “Synthesis of Curcumin
Derivatives via Knoevenagel Reaction Within a Continuously Driven Microfluidic
Reactor Using Polymeric Networks Containing Piperidine as a Catalyst.” Gels
11, no. 4 (2025). https://doi.org/10.3390/gels11040278.
ieee: 'N. Killi, K. Rumpke, and D. Kuckling, “Synthesis of Curcumin Derivatives
via Knoevenagel Reaction Within a Continuously Driven Microfluidic Reactor Using
Polymeric Networks Containing Piperidine as a Catalyst,” Gels, vol. 11,
no. 4, Art. no. 278, 2025, doi: 10.3390/gels11040278.'
mla: Killi, Naresh, et al. “Synthesis of Curcumin Derivatives via Knoevenagel Reaction
Within a Continuously Driven Microfluidic Reactor Using Polymeric Networks Containing
Piperidine as a Catalyst.” Gels, vol. 11, no. 4, 278, MDPI AG, 2025, doi:10.3390/gels11040278.
short: N. Killi, K. Rumpke, D. Kuckling, Gels 11 (2025).
date_created: 2025-04-11T07:12:02Z
date_updated: 2025-04-11T07:13:26Z
department:
- _id: '163'
doi: 10.3390/gels11040278
intvolume: ' 11'
issue: '4'
keyword:
- flow chemistry
- heterogeneous catalysis
- sustainable synthesis
- organo-catalysis
- polymeric gel dots
language:
- iso: eng
main_file_link:
- url: https://www.mdpi.com/2310-2861/11/4/278
publication: Gels
publication_identifier:
issn:
- 2310-2861
publication_status: published
publisher: MDPI AG
status: public
title: Synthesis of Curcumin Derivatives via Knoevenagel Reaction Within a Continuously
Driven Microfluidic Reactor Using Polymeric Networks Containing Piperidine as a
Catalyst
type: journal_article
user_id: '94'
volume: 11
year: '2025'
...
---
_id: '60837'
abstract:
- lang: eng
text: "In light of growing demands for resource efficiency and sustainability in
vehicle engineering, the environmentally compatible separation of structural adhesive
joints is gaining increasing relevance. This study presents a comparative analysis
of two physically based debonding methods: the established hot-air process and
a cryogenic cold process based on liquid nitrogen (LN2). The primary objective
is to assess the ecological impact and process-related sustainability of both
approaches.\r\nExperimental investigations were conducted on a component-representative
triple-sheet structure that simulates common automotive flange joints. Thermal
input was applied either by convective heating using a hot air gun or by direct
cooling through a contact-based LN2 tool. The resulting temperature profiles were
recorded using spatially distributed thermocouples. Subsequently, the outer panel
was selectively debonded to replicate a repair scenario, and the mechanical integrity
of the remaining adhesive joint was evaluated through Mode I testing of L-shaped
specimens. Process data served as input for an Life Cycle Assessment (LCA) according
to DIN EN ISO 14040.\r\nThe cryogenic method achieved a 40% reduction in carbon
footprint compared to the hot-air process (0.337 kg vs. 0.559 kg CO2-equivalents),
primarily due to its shorter process time and more efficient heat transfer. While
the hot-air method’s impact is mainly driven by electrical energy use, that of
the cold method stems from cryogenic media consumption. Notwithstanding certain
disadvantages in specific impact categories, the LN2-based process exhibits a
superior overall ecological performance and signifies a promising solution for
repair- and recycling-oriented adhesive separation in structural vehicle applications."
article_number: '100332'
article_type: original
author:
- first_name: Alex
full_name: Jordan, Alex
id: '62451'
last_name: Jordan
orcid: 0009-0007-9546-6071
- first_name: Lucas
full_name: Hermelingmeier, Lucas
id: '58649'
last_name: Hermelingmeier
- first_name: Julian
full_name: Gilich, Julian
id: '44391'
last_name: Gilich
- first_name: Gerson
full_name: Meschut, Gerson
id: '32056'
last_name: Meschut
orcid: 0000-0002-2763-1246
- first_name: Marco Sebastian
full_name: De Santis, Marco Sebastian
id: '52239'
last_name: De Santis
- first_name: Alexander
full_name: Schlüter, Alexander
id: '103302'
last_name: Schlüter
orcid: 0000-0002-2569-1624
citation:
ama: Jordan A, Hermelingmeier L, Gilich J, Meschut G, De Santis MS, Schlüter A.
Comparison of the economic efficiency and sustainability of two debonding processes
for structurally bonded sills. Journal of Advanced Joining Processes. 2025;12.
doi:10.1016/j.jajp.2025.100332
apa: Jordan, A., Hermelingmeier, L., Gilich, J., Meschut, G., De Santis, M. S.,
& Schlüter, A. (2025). Comparison of the economic efficiency and sustainability
of two debonding processes for structurally bonded sills. Journal of Advanced
Joining Processes, 12, Article 100332. https://doi.org/10.1016/j.jajp.2025.100332
bibtex: '@article{Jordan_Hermelingmeier_Gilich_Meschut_De Santis_Schlüter_2025,
title={Comparison of the economic efficiency and sustainability of two debonding
processes for structurally bonded sills}, volume={12}, DOI={10.1016/j.jajp.2025.100332},
number={100332}, journal={Journal of Advanced Joining Processes}, publisher={Elsevier},
author={Jordan, Alex and Hermelingmeier, Lucas and Gilich, Julian and Meschut,
Gerson and De Santis, Marco Sebastian and Schlüter, Alexander}, year={2025} }'
chicago: Jordan, Alex, Lucas Hermelingmeier, Julian Gilich, Gerson Meschut, Marco
Sebastian De Santis, and Alexander Schlüter. “Comparison of the Economic Efficiency
and Sustainability of Two Debonding Processes for Structurally Bonded Sills.”
Journal of Advanced Joining Processes 12 (2025). https://doi.org/10.1016/j.jajp.2025.100332.
ieee: 'A. Jordan, L. Hermelingmeier, J. Gilich, G. Meschut, M. S. De Santis, and
A. Schlüter, “Comparison of the economic efficiency and sustainability of two
debonding processes for structurally bonded sills,” Journal of Advanced Joining
Processes, vol. 12, Art. no. 100332, 2025, doi: 10.1016/j.jajp.2025.100332.'
mla: Jordan, Alex, et al. “Comparison of the Economic Efficiency and Sustainability
of Two Debonding Processes for Structurally Bonded Sills.” Journal of Advanced
Joining Processes, vol. 12, 100332, Elsevier, 2025, doi:10.1016/j.jajp.2025.100332.
short: A. Jordan, L. Hermelingmeier, J. Gilich, G. Meschut, M.S. De Santis, A. Schlüter,
Journal of Advanced Joining Processes 12 (2025).
date_created: 2025-07-30T11:04:28Z
date_updated: 2026-01-06T08:22:54Z
department:
- _id: '157'
- _id: '876'
- _id: '321'
- _id: '9'
doi: 10.1016/j.jajp.2025.100332
intvolume: ' 12'
keyword:
- Sustainable debonding
- Structural adhesives
- Sustainable joining technologies
- Life Cycle Assessment (LCA)
- Automotive repair process
- Economically efficient debonding
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://www.sciencedirect.com/science/article/pii/S2666330925000536?via%3Dihub
oa: '1'
publication: Journal of Advanced Joining Processes
publication_identifier:
issn:
- 2666-3309
publication_status: published
publisher: Elsevier
quality_controlled: '1'
status: public
title: Comparison of the economic efficiency and sustainability of two debonding processes
for structurally bonded sills
type: journal_article
user_id: '103302'
volume: 12
year: '2025'
...
---
_id: '55999'
abstract:
- lang: eng
text: Clean hydrogen is a key aspect of carbon neutrality, necessitating robust
methods for monitoring hydrogen concentration in critical infrastructures like
pipelines or power plants. While semiconducting metal oxides such as In2O3 can
monitor gas concentrations down to the ppm range, they often exhibit cross-sensitivity
to other gases like H2O. In this study, we investigated whether cyclic optical
illumination of a gas-sensitive In2O3 layer creates identifiable changes in a
gas sensor´s electronic resistance that can be linked to H2 and H2O concentrations
via machine learning. We exposed nanostructured In2O3 with a large surface area
of 95 m2 g-1 to H2 concentrations (0-800 ppm) and relative humidity (0-70%) under
cyclic activation utilizing blue light. The sensors were tested for 20 classes
of gas combinations. A support vector machine achieved classification rates up
to 92.0%, with reliable reproducibility (88.2 ± 2.7%) across five individual sensors
using 10-fold cross-validation. Our findings suggest that cyclic optical activation
can be used as a tool to classify H2 and H2O concentrations.
article_type: original
author:
- first_name: 'Dominik '
full_name: 'Baier, Dominik '
last_name: Baier
- first_name: 'Alexander '
full_name: 'Krüger, Alexander '
last_name: Krüger
- first_name: 'Thorsten '
full_name: 'Wagner, Thorsten '
last_name: Wagner
- first_name: Michael
full_name: Tiemann, Michael
id: '23547'
last_name: Tiemann
orcid: 0000-0003-1711-2722
- first_name: Christian
full_name: Weinberger, Christian
id: '11848'
last_name: Weinberger
citation:
ama: 'Baier D, Krüger A, Wagner T, Tiemann M, Weinberger C. Gas Sensing with Nanoporous
In2O3 under Cyclic Optical Activation: Machine Learning-Aided Classification of
H2 and H2O. Chemosensors. 2024;12(9):178. doi:10.3390/chemosensors12090178'
apa: 'Baier, D., Krüger, A., Wagner, T., Tiemann, M., & Weinberger, C. (2024).
Gas Sensing with Nanoporous In2O3 under Cyclic Optical Activation: Machine Learning-Aided
Classification of H2 and H2O. Chemosensors, 12(9), 178. https://doi.org/10.3390/chemosensors12090178'
bibtex: '@article{Baier_Krüger_Wagner_Tiemann_Weinberger_2024, title={Gas Sensing
with Nanoporous In2O3 under Cyclic Optical Activation: Machine Learning-Aided
Classification of H2 and H2O}, volume={12}, DOI={10.3390/chemosensors12090178},
number={9}, journal={Chemosensors}, publisher={MDPI}, author={Baier, Dominik and
Krüger, Alexander and Wagner, Thorsten and Tiemann, Michael and Weinberger,
Christian}, year={2024}, pages={178} }'
chicago: 'Baier, Dominik , Alexander Krüger, Thorsten Wagner, Michael Tiemann,
and Christian Weinberger. “Gas Sensing with Nanoporous In2O3 under Cyclic Optical
Activation: Machine Learning-Aided Classification of H2 and H2O.” Chemosensors
12, no. 9 (2024): 178. https://doi.org/10.3390/chemosensors12090178.'
ieee: 'D. Baier, A. Krüger, T. Wagner, M. Tiemann, and C. Weinberger, “Gas Sensing
with Nanoporous In2O3 under Cyclic Optical Activation: Machine Learning-Aided
Classification of H2 and H2O,” Chemosensors, vol. 12, no. 9, p. 178, 2024,
doi: 10.3390/chemosensors12090178.'
mla: 'Baier, Dominik, et al. “Gas Sensing with Nanoporous In2O3 under Cyclic Optical
Activation: Machine Learning-Aided Classification of H2 and H2O.” Chemosensors,
vol. 12, no. 9, MDPI, 2024, p. 178, doi:10.3390/chemosensors12090178.'
short: D. Baier, A. Krüger, T. Wagner, M. Tiemann, C. Weinberger, Chemosensors 12
(2024) 178.
date_created: 2024-09-03T13:49:42Z
date_updated: 2025-11-26T12:14:21Z
ddc:
- '540'
department:
- _id: '2'
- _id: '307'
doi: 10.3390/chemosensors12090178
file:
- access_level: closed
content_type: application/pdf
creator: cweinber
date_created: 2024-09-03T13:58:18Z
date_updated: 2024-09-03T13:58:18Z
file_id: '56000'
file_name: chemosensors-12-00178.pdf
file_size: 3275869
relation: main_file
success: 1
file_date_updated: 2024-09-03T13:58:18Z
has_accepted_license: '1'
intvolume: ' 12'
issue: '9'
keyword:
- resistive gas sensor
- chemiresistor
- semiconductor
- metal oxide
- In2O3
- mesoporous
- hydrogen
- humidtiy
- machine learning
- sustainable
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://www.mdpi.com/2227-9040/12/9/178
oa: '1'
page: '178'
publication: Chemosensors
publication_identifier:
issn:
- 2227-9040
publication_status: published
publisher: MDPI
quality_controlled: '1'
status: public
title: 'Gas Sensing with Nanoporous In2O3 under Cyclic Optical Activation: Machine
Learning-Aided Classification of H2 and H2O'
type: journal_article
user_id: '11848'
volume: 12
year: '2024'
...
---
_id: '43464'
abstract:
- lang: eng
text: Lightweight design is a common approach to reduce energy demand in
the use stage of vehicles. The production of lightweight materials is usually
associated with an increase in energy demand, so the environmental impacts of
lightweight structures need to be assessed holistically using a life cycle assessment.
To estimate the life cycle environmental impacts of a product in its developmental
stage, for example, by life cycle engineering, future changes in relevant influencing
factors must be considered. Prospective life cycle assessment provides methods
for integrating future scenarios into life cycle assessment studies. However,
approaches for integrating prospective life cycle assessment into product development
are limited. The objective of this work is to provide the methodological foundation
for integrating future scenarios of relevant influencing factors in the development
of lightweight structures. The applicability of the novel methodology is demonstrated
by a case study of a structural component in a steel, aluminium, and hybrid design.
The results show that appropriate decarbonisation measures can reduce the life
cycle greenhouse gas emissions by up to 95 percent until 2050. We also found that
shifts in the environmentally optimal design are possible in future scenarios.
Therefore, the methodology and data provided contribute to improved decision-making
in product development.
article_number: '3371'
author:
- first_name: Moritz
full_name: Ostermann, Moritz
id: '44763'
last_name: Ostermann
orcid: https://orcid.org/0000-0003-1146-0443
- first_name: Julian
full_name: Grenz, Julian
last_name: Grenz
- first_name: Marcel
full_name: Triebus, Marcel
id: '66036'
last_name: Triebus
- first_name: Felipe
full_name: Cerdas, Felipe
last_name: Cerdas
- first_name: Thorsten
full_name: Marten, Thorsten
id: '338'
last_name: Marten
- first_name: Thomas
full_name: Tröster, Thomas
id: '553'
last_name: Tröster
- first_name: Christoph
full_name: Herrmann, Christoph
last_name: Herrmann
citation:
ama: 'Ostermann M, Grenz J, Triebus M, et al. Integrating Prospective Scenarios
in Life Cycle Engineering: Case Study of Lightweight Structures. Energies.
2023;16(8). doi:10.3390/en16083371'
apa: 'Ostermann, M., Grenz, J., Triebus, M., Cerdas, F., Marten, T., Tröster, T.,
& Herrmann, C. (2023). Integrating Prospective Scenarios in Life Cycle Engineering:
Case Study of Lightweight Structures. Energies, 16(8), Article 3371.
https://doi.org/10.3390/en16083371'
bibtex: '@article{Ostermann_Grenz_Triebus_Cerdas_Marten_Tröster_Herrmann_2023, title={Integrating
Prospective Scenarios in Life Cycle Engineering: Case Study of Lightweight Structures},
volume={16}, DOI={10.3390/en16083371},
number={83371}, journal={Energies}, publisher={MDPI AG}, author={Ostermann, Moritz
and Grenz, Julian and Triebus, Marcel and Cerdas, Felipe and Marten, Thorsten
and Tröster, Thomas and Herrmann, Christoph}, year={2023} }'
chicago: 'Ostermann, Moritz, Julian Grenz, Marcel Triebus, Felipe Cerdas, Thorsten
Marten, Thomas Tröster, and Christoph Herrmann. “Integrating Prospective Scenarios
in Life Cycle Engineering: Case Study of Lightweight Structures.” Energies
16, no. 8 (2023). https://doi.org/10.3390/en16083371.'
ieee: 'M. Ostermann et al., “Integrating Prospective Scenarios in Life Cycle
Engineering: Case Study of Lightweight Structures,” Energies, vol. 16,
no. 8, Art. no. 3371, 2023, doi: 10.3390/en16083371.'
mla: 'Ostermann, Moritz, et al. “Integrating Prospective Scenarios in Life Cycle
Engineering: Case Study of Lightweight Structures.” Energies, vol. 16,
no. 8, 3371, MDPI AG, 2023, doi:10.3390/en16083371.'
short: M. Ostermann, J. Grenz, M. Triebus, F. Cerdas, T. Marten, T. Tröster, C.
Herrmann, Energies 16 (2023).
date_created: 2023-04-13T09:11:33Z
date_updated: 2023-04-13T09:19:56Z
department:
- _id: '9'
- _id: '321'
- _id: '149'
doi: 10.3390/en16083371
intvolume: ' 16'
issue: '8'
keyword:
- Life Cycle Engineering
- Life Cycle Assessment
- Lightweight Design
- Prospective LCA
- Future-oriented LCA
- Energy System
- Material production
- Sustainable production
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://www.mdpi.com/1996-1073/16/8/3371
oa: '1'
publication: Energies
publication_identifier:
issn:
- 1996-1073
publication_status: published
publisher: MDPI AG
quality_controlled: '1'
status: public
title: 'Integrating Prospective Scenarios in Life Cycle Engineering: Case Study of
Lightweight Structures'
type: journal_article
user_id: '44763'
volume: 16
year: '2023'
...