Results 141 to 150 of about 219,799 (293)

Constant propellant use rendezvous scenario across a launch window for refueling missions [PDF]

Active rendezvous of an unmanned spacecraft with the Space Transportation System (STS) Shuttle for refueling missions is investigated. The operational constraints facing both the maneuvering spacecraft and the Shuttle during a rendezvous sequence are ...
Hametz, M. E., Whittier, R.
core   +1 more source

Pharmaceuticals Made with Hydrogen: A Sustainable and Efficient Approach Using Flow Synthesis

Chemistry – A European Journal, EarlyView.
We demonstrate a sustainable strategy for pharmaceutical manufacturing by combining hydrogen, heterogeneous catalysis, and continuous flow synthesis. The development of novel catalysts and their application in a multi‐step synthesis of donepezil enabled a highly productive process with no intermediate purification.
Shū Kobayashi, Haruro Ishitani
wiley   +1 more source

Impact of Distillation Column Design on Potential for the Integration of Mechanical Vapor Recompression

Chemie Ingenieur Technik, EarlyView.
Mechanical vapor recompression integration in distillation is analyzed, focusing on feed preheating and column pressure drop. Binary methanol–water and benzene–toluene separations are studied to identify optimal designs, which are further assessed in a bioethanol vacuum distillation sequence regarding energetic, ecological, and economic performance ...
Thorben Hochhaus, Sebastian Siepmann, Marcus Grünewald, Julia Riese   +3 more
wiley   +1 more source

Substantial aircraft contrail formation at low soot emission levels. [PDF]

Nature
Voigt C, Märkl R, Sauer D, Dischl R, Renard C, Seeliger K, Yu F, Kaufmann S, Bräuer T, Jurkat-Witschas T, Le Chenadec G, Moreau J, Requena-Esteban E, Bonne N, Vals M, Roche A, Zelina J, Dörnbrack A, Eirenschmalz L, Heckl C, Horst E, Lichtenstern M, Marsing A, Neumann G, Roiger A, Scheibe M, Stock P, Giez A, Eckel G, Le Clercq P.   +29 more
europepmc   +1 more source

Influence of Particle Size, Moisture, and Cloud Density on Wood Dust Ignition

Chemie Ingenieur Technik, EarlyView.
The ignition and combustion of particle clouds are strongly affected by particle interactions. This study uses spectroscopy to examine effects of particle size, water content, and cloud density. Results show ignition delay rises with larger size and density, whereas combustion duration depends mainly on water and density due to moisture‐driven ...
Matteo Giesen, Daniel Bernhardt, Michael Beckmann   +2 more
wiley   +1 more source

Reassessing boreal wildfire drivers enables high-resolution mapping of emissions for climate adaptation. [PDF]

Sci Adv
Eckdahl JA, Nieradzik L, Rütting L.
europepmc   +1 more source

Global and Detailed Calculation of Tube Wall Temperature in a Process Furnace Steam Superheater

Chemie Ingenieur Technik, EarlyView.
This study presents a comparison between an iterative global model and multiple approaches to a new non‐iterative model with the purpose of predicting tube wall temperature of a superheater. The results show that the non‐iterative method achieves sufficient accuracy while improving the prediction of local temperature distribution and better ...
Anežka Michálková, Zdeněk Jegla
wiley   +1 more source

Defossilisation of the Energy Supply of a Chemical Site by Integration of a Carnot Battery

Chemie Ingenieur Technik, EarlyView.
This study presents the results of a techno‐economic analysis of CO2‐free energy supply concepts for electricity and heat for the defossilisation of a chemical park in Germany for the model years 2030 and 2045. The focus is on the integration of a Carnot battery with thermal energy storage, which enables the flexible use of green fuels and renewable ...
Martin Bolten, Stefano Giuliano, Gerrit Koll, Judith Jäger, Arnulf Reitze, Michael Roling, Jana Stengler   +6 more
wiley   +1 more source

The climate opportunities and risks of contrail avoidance. [PDF]

Nat Commun
Smith JR, Grobler C, Hodgson PJ, Mukhopadhaya J, Shapiro ML, Mirolo M, Stettler MEJ, Eastham SD, Barrett SRH.   +8 more
europepmc   +1 more source

Hydroprocessing of synthetic kerosene over a non‐sulphided Ni/Al2O3 catalyst: Impact of alcohols and ketones on alkene conversion

The Canadian Journal of Chemical Engineering, EarlyView.
Abstract Synthetic jet fuel containing non‐petroleum‐derived kerosene can be produced from synthetic kerosene obtained through processes that include a hydroprocessing step. The potential use of non‐sulphided (reduced) nickel supported on alumina (Ni/Al2O3) was evaluated as an alternative to sulphided catalysts to saturate alkenes in sulphur‐free ...
Garima Chauhan, Felix Link, Cibele Melo Halmenschlager, Arno de Klerk   +3 more
wiley   +1 more source