Louvain La Neuve Research Articles

Effect of biomass concentration in membrane bioreactor design on alpha factor for two large pilot systems: Case study of mechanical surface aeration and air insufflation system

In the literature, the studies on wastewater treatment process have shown a great interest in aeration system, most of them were performed on small pilot lab-scale. However, it still an important need to provide useful information aiming at reducing the operating costs and providing decision support to choose aeration devices. Considering that membrane bioreactors operating with high biomass concentrations up to 20–30 g of suspended solids (SS) per liter, the present study was carried out on a larger pilot lab-scale ( ± 500 l) of insufflation system and mechanical surface aeration on the same fresh sludge with concentration varying between 4.6 and 19.8 g/l. The comparison with literature data shows good correspondence with values obtained with our insufflation system but a great difference from values obtained in a mechanical system. In addition, this research provides a better insight on the calculation method that can be used to estimate the critical parameters of the oxygen transfer, and analyses the feasibility of air diffusion substitution by surface aeration system of Louvain La Neuve wastewater treatment plant of 13000 population equivalent. This extrapolation proved that a saving of ± 50,000 € per year can be achieved by choosing surface aeration rather than aeration by air insufflation.

Victor Villanueva: Obituary

On the Loss of our Friend VictorVictor was much more than a colleague to me. He was a friend. On Tuesday, the 27th of August, a few days before he passed away, he was an examiner in the final defense of a master student. Although his state of health had already deteriorated to the point of no return, Victor had no intention of giving up on his responsibilities. With his noticeably slower and feeble gait, he reached the examination room a few minutes late. Despite excruciating headache and the fact that his increasing physical debilities were unable to keep up with his mental strength and optimism, he keenly sat through the exam and with genuine interest in the content of the research work presented, asked questions with zeal and excitement, and even proposed a few possible future applications of the work.Just after the exam was over, we all had to move to the main building to sign the official document. Victor struggled again to go up the stairs. By the time he reached the final stair, he was completely out of breath. He was less than a few meters away from the secretary´s office, but his fragile body needed rest. He looked at me, smiled feebly and sat down on a chair to catch his breath. “Give me a few moments Adnan. I shall soon be with you.” was all he could say. Shortly, he mustered up the last few atoms of his strength, and walked into the office to sign the documents. Despite seeing him so ill of health, I simply could not see it coming, not so soon at least. I could not foresee the tragic fact that his would only be the second funeral I would be attending after accompanying him a decade ago to bury his unborn son. Traveling on the wings of memory, I would later recall those sad days of early 2004. I was shell shocked when Victor’s loving son was being laid to rest when he passed away in his mother’s womb after seven months of conception. At that time, I was expecting my own son of the same age and I could not fathom how a father could survive this tragedy. Victor’s immense inner strength of will enabled him to survive this tremendous loss and his failing kidneys till his physical capacities finally surrendered to the indifferent and often cruel course of nature.Victor was born in Celaya, Guanajuato, Mexico, on March 1, 1970. Shortly afterwards, his family moved to Zamora, Michoacán, where he received elementary and high school education. Later he moved to Morelia and attended the University of Michoacan from where he received his bachelor degree in 1993. After carrying out his master at Metropolitan University (Iztapala) in Mexico City in 1995, he joined University of Guanajuato (Leon, Guanajuato, Mexico). There he obtained his doctoral degree under thetitle: Quantization of Gauge Systems on Riemannian Manifolds under the supervision of Prof. J. L. Lucio from University of Guanajuato and Prof. J. Govaerts from the Universite Catholique de Louvain-la Neuve, Belgium (1999). As a researcher, Victor had about 20 articles in international journals to his credit and more than a 100 citations. Though his academic achievements are numerous and earned him a respectable place in the national scientific community, I would not dwell on it more. I miss him as a friend.

Single-Event Transients in Readout Circuitries at Low Temperature Down to 50 K

This paper presents the impact of cryogenic temperatures, down to 50 K, on the single-event transient (SET) sensitivity of two readout circuits of infrared image sensor designed by Sofradir. Experimental SETs data obtained under heavy ions at the Universite Catholique de Louvain la Neuve facility are described, and the temperature impact on the SET cross sections is presented. The analysis of experimental sensitivity trends is completed by means of MUSCA SEP3 tool.

Effects of coupling to breakup channels in reactions induced by weakly bound and halo nuclei

The experimental elastic scattering angular distributions of the collisions involving the weakly bound nuclei 6,7 Li and the halo nucleus 6 He on the same 64 Zn target at several energies around the Coulomb barrier were measured at the Laboratori Nazionali del Sud (LNS, Italy), and the Cyclotron Research Center, Louvain La Neuve (Belgium), respectively. The experimental elastic scattering angular distributions of the 6,7 Li + 64 Zn systems have been analyzed within the continuumdiscretized coupled-channels method, while the 6 He + 64 Zn data have been compared with both continuum-discretized coupled-channels and coupled-reaction-channels calculations.

Single Event Gate Rupture in EMCCD technology

The high electric fields (typically 3 MV/cm2 interpoly field) utilised in Electron Multiplying Charged Coupled Devices (EMCCDs) reveal a potential vulnerability from Single Event Phenomena (SEP), in particular Single Event Gate Rupture (SEGR). SEGR is where a conduction path between two conductive areas of the CCD is produced, causing device failure. If EMCCDs are to be used for space applications the susceptibility to these events needs to be explored. A positive result from such an investigation can increase the technology readiness level of the device moving it another step closer to being used in space. Testing undertaken at the CYClotron of LOuvain la NEuve (CYCLONE), using the Heavy Ion Facility (HIF), conclusively showed EMCCD technology to have resilience to heavy ions that surpassed initial expectations. The simulations undertaken prior to experiment suggested gate rupture would occur at 20–40 MeV cm2/mg, however Linear Energy Transfers (LETs) greater than 100 MeV cm2/mg proved to not cause a rupture event. Within the radiation belts heavy ions with an LET greater than 60 MeV cm2/mg are not very common when compared to the fluxes used at the HIF. Possible reasons for this result are discussed in this work, leading to a conclusion that EMCCD technology is a secure choice for space flight.

Work inequalities in the crisis: evidence from Europe

'Since the successive crises erupted, the increase in inequality has not been addressed. This important publication offers a comprehensive overview of recent developments in the workplace. It will help to promote a different policy agenda that is desperately needed to overcome the causes and consequences of the crisis, namely addressing work inequalities.' –Philippe Pochet, Catholic University of Louvain la Neuve, Belgium, and General Director of the European Trade Union Institute (ETUI), Brussels, Belgium

Activated carbon from olive kernels in a two-stage process: Industrial improvement

Activated carbons have been prepared from olive kernels and their adsorptive characteristics were investigated. A two stage process of pyrolysis-activation has been tested in two scales: (a) laboratory scale pyrolysis and chemical activation with KOH and (b) pilot/bench scale pyrolysis and physical activation with H 2O–CO 2. In the second case, olive kernels were first pyrolysed at 800 °C, during 45 min under an inert atmosphere in an industrial pyrolyser with a throughput of 1 t/h (Compact Power Ltd., Bristol, UK). The resulting chars were subsequently activated with steam and carbon dioxide mixtures at 970 °C in a batch pilot monohearth reactor at NESA facility (Louvain-la Neuve, Belgium). The active carbons obtained from both scales were characterized by N 2 adsorption at 77 K, methyl-blue adsorption (MB adsorption) at room temperature and SEM analysis. Surface area and MB adsorption were found to increase with the degree of burn-off. The maximum BET surface area was found to be around 1000–1200 m 2/g for active carbons produced at industrial scale with physical activation, and 3049 m 2/g for active carbons produced at laboratory with KOH activation. The pores of the produced carbons were composed of micropores at the early stages of activation and both micropores and mesopores at the late stages. Methylene blue removal capacity appeared to be comparable to that of commercial carbons and even higher at high degrees of activation.

Essay: The miracle boat

Essay: The miracle boat

Beet necrotic yellow vein virus (benyvirus)

<i>Beet necrotic yellow vein virus</i> (<i>benyvirus</i>)

Portaclamp in video-assisted minimally invasive cardiac surgery: Surgical technique and preliminary clinical experience

Video-assisted minimally invasive cardiac surgery (VAMICS) is currently performed with various indications. However, despite the increasing evidence of its effectiveness, new approaches have to be defined to simplify this procedure, minimize its potential complications and limit its costs, for a wider use in the surgical community. The limited access to the aorta is a key point in VAMICS and mandates specific clamping modalities with their own limitations, costs and drawbacks. The Portaclamp (Cardio Life Research SA, Louvain la Neuve, Belgium), a new autoguided extravascular aortic cross-clamping system, has been recently proposed to facilitate VAMICS. Herein, we describe the Portaclamp approach and report our indications and preliminary clinical experience so to define its role in VAMICS.

Public Awareness Activities: Creating NUCLEUS

In the spring of 1998, a meeting was called by Jules Deutsch, Adriaan van der Woude, and Alan Shotter at Louvain la Neuve to discuss what measures might be taken to improve the image of nuclear physics. This was the beginning of PANS, Public Awareness of Nuclear Science. We quickly recognized that there were three distinct groups to educate: the general public, policymakers, and scientists outside the nuclear field. Of the three, I think we were most concerned with educating the general public, for a number of reasons: (i) it is the most challenging task; (ii) the general public in a democracy have real power, especially when it comes to spending taxpayers' money; (iii) the next generation of nuclear physicists, upon which the continuation of our subject depends, are the younger part of the general public; (iv) the problem is deep—many examples were discussed of the irrationality infecting modern life, and the particular fears roused by the very word “nuclear,” as discussed at length in the book Nuclear Fear by Spencer Weart. It was apparent that there were clear national differences concerning the nature of the problem, but a small number of projects were agreed on that could be the subject of collaborations involving nuclear physicists from different countries. One of these projects was a popular book in nuclear physics, and to create this, Bjorn Jonson from Sweden, Teresa Peña from Portugal, and Jim Al-Khalili and myself from the UK formed a team, with me as “driver” (Jules Deutsch's term). In the UK, at least, there has been a real boom in the production of popular scientific books: arguably too many, so that good ones have difficulty being noticed. However, among all the books on space and time, Schrödinger's kittens, the quark explosion, trilobites, and transistors, there was nothing on nuclear physics. What follows is an account of how we set about changing that and how the book NUCLEUS: A Trip to the Heart of Matter came into being.

Beet necrotic yellow vein benyvirus

Beet necrotic yellow vein benyvirus

Study of the 18F(p,α) 15O reaction for application to nova γ-ray emission

The 18F(p,α) 15O reaction is recognized as one of the most important reaction for nova gamma-ray astronomy as it governs the early ≤ 511 keV emission. However, its rate remains largely uncertain at nova temperatures due to unknown low-energy resonance strengths. In order to better constrain this reaction rate, we have studied the one-nucleon transfer reaction, D( 18F,pα) 15N, at the CRC-RIB facility at Louvain La Neuve.

High-energy neutron detection and spectrometry with superheated emulsions

The response of some superheated emulsions was investigated using quasi-monoenergetic neutron beams in the 46–134MeV energy range at the Université Catholique de Louvain, Louvain la Neuve, Belgium and at The Svedberg Laboratory, Uppsala, Sweden. In order to determine the detector response to the high-energy beams, the spectra of incident neutrons were folded over functions modeled after the cross-sections for the neutron-induced production of heavy ions from the detector elements. The cross-sections for fluorine and chlorine were produced in this work by means of the Monte Carlo high-energy transport code HADRON based on the cascade-exciton model of nuclear interactions.

Proton dosimetry comparison involving ionometry and calorimetry

A comparison of the absorbed dose to tissue determined by various ionization chambers, Faraday cups, and an A-150 plastic calorimeter was performed in the 200 MeV proton beam of Orsay, France. Four European protontherapy centers (Clatterbridge, UK, Louvain la Neuve, Belgium, and Nice and Orsay, France) participated in the comparison. An agreement of better than 1% was observed in the absorbed dose to A-150 measured with the different chambers of the participating groups. The mean ratio of the absorbed dose to A-150 determined with the calorimeter to that determined by the different ionization chambers in the different irradiation conditions was found to be 0.952 ± 0.007 [1 standard deviation (SD)] according to the code of practice used by all the participating centers, based on Janni's tables of stopping powers and a value of 35.2 J/Coulomb for (W air e) p . A better agreement in the mean ratio calorimeter/chamber, 0.985 ± 0.007 (1 SD) is observed when using the proton stopping power ratio values recently published by the International Commission on Radiation Units and Measurements in Report no. 49. The mean ratio of these doses determined in accordance with the American Association of Physicists in Medicine protocol and using the new recommended stopping power tables becomes 1.002 ± 0.007 (1 SD). Two Faraday cups agree in measured charge to within 0.8%; however, the calculation of dose is underestimated by up to 17%; compared with ion chamber measurements and seems to be very sensitive to measurement conditions, particularly to the distance to the collimator.

Nuclear physics with radioactive beams

Radioactive beams can be produced through two different and complementary ways: firstly by the production of radioactive nuclei at rest, followed by their acceleration using conventional techniques. This method is the best for producing low-energy radioactive beams. The second method is by the fragmentation of high-energy heavy ion beams (over 30 MeV/u), followed by the selection and purification of a given secondary beam using magnetic spectrometers. This technique leads to high-energy radioactive beams. Both methods have now been used in several laboratories in the World (Berkeley, Ganil, Louvain la Neuve, Riken, GSI Darmstadt). Examples of the corresponding experimental equipment are presented, and especially Lise 3, Sissi and the Spiral project at Ganil. Radioactive beams have been used for several purposes in nuclear physics. They constitute the fastest technique ever used for transferring exotic nuclei from the production point to a well-shielded place where detectors can be operated for studying their properties. They are used to induce nuclear reactions which reveal new information on nuclear structure. In the domain of nuclear astrophysics, radioactive beams are used to measure, through direct or indirect methods, the cross sections for reactions of crucial interest in nucleosynthesis. Finally, radioactive beams of light positron emitters, such as 19Ne have considerable interest for medical purposes and especially in the growing field of heavy-ion radiotheraphy.

4983510 Enzymes immobilized on latex polymer particles for use with an amino acid electrosensor: Pierre F Lardinois, Paul Rouxhet, William E E Stone, Kenneth Baker, Alain E Baudichau, Louvain la Neuve, Belgium assigned to Monsanto Company

4983510 Enzymes immobilized on latex polymer particles for use with an amino acid electrosensor: Pierre F Lardinois, Paul Rouxhet, William E E Stone, Kenneth Baker, Alain E Baudichau, Louvain la Neuve, Belgium assigned to Monsanto Company

4983510 Enzymes immobilized on latex polymer particles for use with an amino acid electrosensor: Pierre F Lardinois, Paul Rouxhet, William E E Stone, Kenneth Baker, Alain E Baudichau, Louvain la Neuve, Belgium assigned to Monsanto Company

4983510 Enzymes immobilized on latex polymer particles for use with an amino acid electrosensor: Pierre F Lardinois, Paul Rouxhet, William E E Stone, Kenneth Baker, Alain E Baudichau, Louvain la Neuve, Belgium assigned to Monsanto Company

European Geophysical Society

The 10th General Assembly of the European Geophysical Society (EGS) took place from July 30 to August 3, 1984 at the Catholic University of Louvain, Louvain La Neuve, Belgium. Over 320 papers were presented at the Assembly, and an encouraging sign for the EGS was the continued and increased attraction of the meeting to scientists from outside Europe (particularly from North America, Australia, and Japan).The assembly witnessed several exciting developments within the EGS: for example, the recent innovation of a special interest group (Chairman: F. Neubauer, University of Köln, Federal Republic of Germany) in Planetary Physics stimulated the convening of a special symposium in Louvain La Neuve on planetary exploration and future planetary missions, at which the objectives of the special interest group were formulated in the light of the most recent developments in the field. A panel discussion during the symposium supported the Kepler mission to Mars as the next logical step in a European program of planetary exploration.