Calorimetric control of fed-batch fermentations

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Climate change is expected to affect precipitation intensity and soil temperature and indirectly impact the release of leached dissolved organic carbon (LDOC) from leaf litter during the early stages of its decomposition, which could affect the health and function of forest soil ecosystems. Here, we experimentally investigate the spatially-explicit impact of LDOC on the forest soil microbiome and the associated biogeochemical processes. Homogenized soil columns were subjected to realistic artificial precipi

This work advances the quantitative validation of SOLPS-ITER against TCV ohmic L-mode discharges. It demonstrates that the treatment of the ion parallel heat-flux limiter and the assumptions adopted for chemical sputtering provide a consistent explanation for the divertor over-cooling and excessive divertor density predicted by earlier simulations. A systematic heat-flux-limiter scan highlights that a strong restriction of ion heat conduction significantly reduces both electron target temperatures T e,t and

This study provides new insights into multi-ion heat transport and the validation of neoclassical theory at the edge of H-mode plasmas. Utilizing a high-resolution main ion charge exchange recombination spectroscopy system, the first characterization of edge deuterium temperature (TD) and toroidal velocity ( v ϕ , D ) in a metal wall environment is presented. Dedicated experiments which examine the impact of the heating mix on TD and v ϕ , D in the ASDEX Upgrade tokamak are discussed. An unexpected temperat

This study presents a systematic experimental investigation into the thermal-fluidic characteristics of a novel manifold ring-microchannel heat sink operating under periodic heat flux conditions. The research focuses on analyzing the coupled thermal responses and flow instability phenomena across a wide range of disturbance frequencies (0.5–500 Hz) and mass flux conditions (1.0–3.44 g/s). Through comprehensive measurements of wall temperature distributions, pressure fluctuations, and high-speed visualizatio

Buildings are a substantial, and sometimes overlooked, consumer of energy, accounting for roughly a third of global primary energy consumption, with roughly half of that being used for heating and cooling. While the replacement rate of buildings is low, and energy retrofits are challenging, if possible at all, the installation of an advanced control system is comparatively quick and simple. This may be done in an effort to reduce a building's energy consumption by avoiding excessive heating or cooling, but

The energy integration of industrial complexes and urban agglomerations has many benefits in terms of rational energy use and reduced environmental impact, especially during scenarios of supply chain uncertainty and volatile market prices. In fact, the diversification of the energy inputs along with the waste heat upgrading through the implementation of optimal energy integration systems become crucial for defining the new energy pathways towards a sustainable and robust energy security. The enhanced waste

Aerobic granular sludge (AGS) is an emerging technology offering an alternative wastewater treatment with a reduced footprint compared to conventional activated sludge systems. Basic understanding of AGS processes has mainly been obtained in laboratory-scale studies with simple synthetic wastewaters containing volatile fatty acids (VFA) as main carbon sources. Yet, the bacterial communities of AGS treating municipal wastewater have been much less investigated. Two approaches were applied here to assess the

The project VeganPeat is described in this poster. IN particular, the workpackage oncerning the quantification of 14C in soil respired CO2 to detect the role of vascular plant abundance in promoting the decomposition of old organic matter in two peatlands located at different altitude.

Central solar heating plant is one of the most profitable, the most efficient and the most easily installable solar technology. However, there is significant limitations for its installation on all the northern roof. There is a gap between the summer heat production and the consumption during this season and inversely for the winter. Then, adding a storage medium ,as a buffer for the heat supply, permits to deal correctly with these gaps. The aim of this project is to modelize a storage concept including a

After a brief review of the current research on the production of synthetic natural gas (SNG) from lignocellulosic biomass by gasification and methanation, this paper presents detailed thermo-economic process optimisation of the polygeneration of SNG, power and heat. Based on a previously developed model, all suitable candidate configurations of a superstructure of promising technologies for the individual conversion steps are optimised with respect to the overall efficiency and investement cost with an evo

The conversion of lignocellulosic biomass to methane is a promising way to distribute a renewable resource as a versatile energy vector in an existing grid. Potentially more efficient than the production of liquid fuels, it can be used as Synthetic Natural Gas (SNG) as automotive fuel or in combined heat and power (CHP) applications at any scale. Based on a detailed thermo-economic process model for the thermochemical production of SNG (Gassner and Maréchal, Biomass and Bioenergy 33 (2009), 1587-1604), the

The curing reaction of an epoxy resin [diglycidyl ether of bisphenol A (DGEBA)] combined with a methyl-hexahydrophtalic anhydride (MHHPA) hardener and a benzyldimethylamine (BDMA) accelerator was studied over a temperature range of 60 140°C to build its isothermal time-temperature-transformation (TTT) cure diagram. This includes gelation and vitrification measurements using rheological measurement techniques, monitoring of the glass transition temperature and the reaction kinetics by differential scanning c

This paper introduces a novel of mini-hybrid solar power plant integrating a field of solar concentrators, two superposed Organic Rankine Cycles (ORC) and a (bio)Diesel engine. Turbines for the organic Rankine Cycles are hermetic scroll expander-generators. Sun tracking solar collectors are composed of rows of flat mirror bands (CEP) arranged in a plane, which focus the solar energy onto a collector tube similar to those used in SEGS plant in California. The waste heat from both the exhaust gases and block

A unique bench-scale heat flux calorimeter is described, which is capable of detecting the low heat signal of an animal cell culture (a max. of 200 mW/l is produced with a batch culture of SF9 insect cells). After the tech. modifications that enhanced the sensitivity of a com. heat flux reaction calorimeter, RC1 from Mettler-Toledo AG. Switzerland, the behavior of this system is analyzed here under biol. operation conditions. Not only the heat flows provoked by the bioprocess parameters largely det. the fin

OPTIMIZATION OF A SEMI-BATCH REACTION SYSTEM UNDER SAFETY CONSTRAINTS O. Ubrich+, B. Srinivasan*, F. Stoessel+, D. Bonvin* * Novartis Services AG, CH-4002 Basel, Switzerland Institut d’ utomatique, Ecole Polytechnique Fédérale de Lausanne A CH-1015, Lausanne, Switzerland * Fax: +41 21 693 2574 and e-mail: dominique.bonvin@epfl.ch + An important objective in the chemical industry is to find the operating conditions that maximize profit while ensuring safe operation. The safety considerations arise from the e

The objective of this study was to characterize the dynamic adaptation of the oxidative capacity of Saccharomyces cerevisiae to an increase in the glucose supply rate and its implications for the control of a continuous culture designed to produce biomass without allowing glucose to be diverted into the reductive metab. Continuous cultures subjected to a sudden shift-up in the diln. rate showed that the glucose uptake rate increased immediately to the new feeding rate but that the oxygen consumption could n

Many models have been developed to describe the kinetics of the free radical polymn. of Me methacrylate (MMA). However, they are restricted to low temps., e.g., below the glass transition temp. of the polymer, Tg. In this work, kinetics of bulk and soln. polymn. of MMA were detd. by differential scanning calorimetry (DSC) for temps. above Tg, i.e. 130-165 DegC. On the basis of our own exptl. results (high temps.) and those published in the literature (low temps.), it has been shown that with small modificat

The radical addn. co-polymn. of 2-hydroxyethyl methacrylate and Bu acrylate is carried out in a continuously operating Buss-Kneader. To calc. temp. profiles over the length of the kneader the heat balance is solved. For the heat transfer coeff. a model based on the penetration theory is used. This model is exptl. verified. The reaction kinetics of the radical addn. polymn. are studied in a differential scanning calorimeter. The polymn. kinetics are modeled using non-stationary radical concns. The calcd. tem

Heat generation is a very conspicuous phenomenon in large scale bioreactors and could in principle quite easily be measured by the temp. increase of the cooling water. Taking yeast cultures growing on a mixed oxido-reductive metab. for various reasons as an example, this paper demonstrates how heat dissipation measurements may be used in combination with other convenient online measurements order to obtain a quant. estn. of the nature of the on-going metab. and of the current overall stoichiometry. The appl

Collective Thomson scattering, using a high-power pulsed D2O laser at 385-mu-m and a heterodyne receiver system, has provided local ion temperature (T(i)) measurements of the plasma in the tokamak chauffage Alfven (TCA) tokamak. Recent improvements in the noise-equivalent power of the Schottky barrier diode mixers permitted us to achieve a typical precision of +/- 12% for a single shot measurement at densities above 10(20) m-3. Even at densities of standard TCA discharges (5 x 10(19) m-3) the uncertainty is

Calorimetric control of fed-batch fermentations

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Spatially explicit impact of enhanced leaf litter leaching on the forest soil microbiome

Advancing SOLPS-ITER validation with TCV L-mode discharges

Investigation of multi-ion heat and neoclassical transport using new edge main ion measurements at ASDEX Upgrade

Thermal responses and flow instability of manifold ring-microchannel heat sink applied for periodic heat flow conditions

Applications of Data-driven Predictive Control to Building Energy Systems

A systematic framework for the multi-time integration of industrial complexes and urban systems

Influence of Wastewater Composition on the Microbial Communities of Aerobic Granular sludge

Climate change, vegetation dynamics and carbon cycling in peatlands: the role of vascular plants in CO2 sequestration

INTEGRATION OF A SEASONAL STORAGE

Thermo-economic optimisation of the polygeneration of synthetic natural gas (SNG), power and heat from lignocellulosic biomass by gasification and methanation

Optimal technologies for the thermochemical production of Synthetic Natural Gas (SNG) from lignocellulosic biomass

TTT - Cure diagram of an anhydride-cured epoxy system including gelation, vitrification, curing kinetics model and monitoring of the glass transition temperature

Small Hybrid Solar Power System

The development and characterization of a high resolution bio-reaction calorimeter for weakly exothermic cultures

Optimization of a Semi-Batch Reaction System under Safety Constraints

Identification and control of oxidative metabolism in Saccharomyces cerevisiae during transient growth using calorimetric measurements

Modeling of the free radical polymerization of methylmethacrylate up to high temperature

Radical addition polymerization of acrylates in a Buss-Kneader

Calorimetry of technical microbial reactions

Ion Temperature-Measurements in a Tokamak by Collective Thomson Scattering