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L'évolution des propriétés magnétiques d'alliages Fe-3 %Si à grains non orientés avec les déformations plastiques a été évaluée à l'aide d'une technique expérimentale permettant des mesures directes sur éprouvettes de traction. Une dégradation importante de ces caractéristiques est observée aux faibles et moyennes amplitudes d'excitation magnétique. Cet effet s'estompe pour les valeurs les plus élevées du champ magnétique. A mesure qu'augmente la déformation, les dislocations s'organisent en cellules quasi hexagonales sur le palier de L$\ddot{\rm u}$ders, puis, en début d'écrouissage, se regroupent en petits amas faiblement denses séparant des zones de métal où existent des dislocations isolées. Ces deux configurations sont les plus nocives pour les propriétés magnétiques. Aux fortes déformations, des murs de dislocations très denses se forment, mais ne dégradent pas davantage les caractéristiques magnétiques. Nous montrons que le modèle du potentiel conservatif ne s'applique pas à nos résultats expérimentaux tandis que celui de courbure des parois pourrait être mieux adapté. L'évolution du champ coercitif avec la contrainte plastique pure appliquée au matériau suit une loi en deux stades, contrairement aux trois stades obtenus sur du Fe polycristallin de haute pureté par d'autres auteurs.

Zur Hydroaminomethylierung von Olefinen in nahe- bzw. überkritischem Ammoniak wird ein neues Verfahren entwickelt. Dazu wird ein Messstand zur Ermittlung thermodynamischer Daten von Reaktand- und möglichen Produktgemischen eingerichtet und eine genaue Untersuchung der kritischen Reaktionsparameter durchgeführt. Diese thermodynamischen Daten (kritische Punkte (p, T)) werden mittels Opaleszenzmessungen in einer Sichtzelle erhalten. Bimetallische Rh/Ir-Katalysatoren erreichen in einem Katalysatorscreening bei der Hydroaminomethylierung von 1-Octen als Modellolefin Ausbeuten an primären Aminen zwischen 45 und 60 % bei durchschnittlichen n/i-Verhältnissen von 56:44. Die Arbeitsdrücke bewegen sich bei 140 °C im Bereich von 190 – 240 bar. Daneben werden 15 – 22 % sekundäre Amine (R2NH), 4 – 7 % Octan, 3 – 4 % isomere Octene und geringe Mengen an sekundären und tertiären Kondensationsprodukten gefunden.

Hydroaminomethylation of olefins to synthesize amines in supercritical ammonia was studied for the first time. In the presence of a bimetallic Rh‐Ir catalyst system the reaction of 1‐octene with CO, H2, and ammonia led to high‐yield nonylamines. The effect of various reaction conditions such as temperature and pressure was investigated. Furthermore, the influence of different co‐solvents like toluene or methanol was examined. The yield of primary amines could be increased up to 60 % under optimized reaction conditions.

Aus industrieller Sicht ist die Hydroformylierung interner Olefine zu terminalen Aldehyden besonders interessant, da Mischungen interner Olefine deutlich billiger sind als das terminale Olefin. Hieraus rührt ein besonderes Interesse an der Entwicklung neuer Katalysatoren, die interne Olefine im wässrigen Zweiphasensystem hydroformylieren können.

Clinical recurrences of Herpes simplex virus type 1 (HSV‐1)‐associated genital herpes are thought to be caused by reactivation of latent endogenous HSV‐1. However, the possibility of reinfection with exogenous HSV‐1 cannot be excluded. This study aimed to determine the incidence of genital HSV‐1 superinfection in patients by investigating the genotype of sequential HSV‐1 isolates obtained from the same anatomical site of patients with clinical recurrences of genital HSV‐1 recurrent genital herpes. Sequential genital HSV‐1 isolates were genotyped by PCR amplification of the hypervariable regions located within the HSV‐1 genes US1 and US12. Whereas the sequential HSV‐1 isolates in 11 of the 13 patients studied had the same genotypes, the sequential isolates of 2 patients showed a different genotype. The data suggest that HSV‐1‐induced recurrent genital herpes can be associated with genital reinfection with an exogenous HSV‐1 strain. J. Med. Virol. 73:601–604, 2004. © 2004 Wiley‐Liss, Inc.

In this paper, we report on novel Rh/phosphonate−phosphine catalysts for the aqueous two-phase hydroformylation of long-chain olefins. The amphiphilic ligands Ph2P−(CH2)10−PO3Na2 and Ph2P−(CH2)12−PO3Na2 have been shown to form Rh catalysts that are superior to Rh/TPPTS systems. Aldehyde selectivities higher than 95% and high activities (e.g., TOF of 660 h^-1 at 88% yield) were achieved. Counterions such as Na⁺, K⁺, NH4⁺, and NH3Pr⁺ influence the catalyst retention, whereas the lowest rhodium losses into the organic phase were found with a sodium phosphonate ligand. Phase separation by simple decantation was accelerated when methanol was added to the biphasic system.

We have developed a novel system for expansion of gene-modified hematopoietic stem/progenitor cells to overcome the low efficiency of current gene transfer methodology. This system involves ‘selective amplifier genes’, that encode fusion proteins between the granulocyte colony-stimulating factor receptor (GCR) and the hormone-binding domain of estrogen receptor (ER). Hematopoietic progenitors expressing the chimeras showed estrogen-responsive growth in a controllable manner. However, endogenous estrogen may activate the fusion proteins in vivo, depending on the hormonal status of the subjects. We replaced ER with a mutant receptor (TmR) which specifically binds to 4-hydroxytamoxifen (Tm), to overcome limitations with wild-type ER. Interleukin-3 (IL-3)-dependent Ba/F3 cells and hematopoietic progenitor cells transduced with the resultant fusion proteins (GCRTmR and ΔGCRTmR) were examined for ligand-inducible growth. GCRTmR- and ΔGCRTmR-expressing Ba/F3 showed IL-3-independent growth in response to Tm, while the cells were unresponsive to estrogen at concentrations up to 10⁻⁷–10⁻⁶ M. Furthermore, murine bone marrow cells transduced with GCRTmR and ΔGCRTmR formed colonies in methylcellulose medium in response to Tm, while virtually no colonies appeared with 10⁻⁷ M estrogen or without cytokines. These results suggest that influences of the endogenous estrogen can be almost eliminated by using the GCRTmR/Tm or ΔGCRTmR/Tm system to expand gene-modified hematopoietic stem/progenitor cells. Copyright © 1999 John Wiley & Sons, Ltd.

We have developed a novel system for expansion of gene‐modified hematopoietic stem/progenitor cells to overcome the low efficiency of current gene transfer methodology. This system involves ‘selective amplifier genes’, that encode fusion proteins between the granulocyte colony‐stimulating factor receptor (GCR) and the hormone‐binding domain of estrogen receptor (ER). Hematopoietic progenitors expressing the chimeras showed estrogen‐responsive growth in a controllable manner. However, endogenous estrogen may activate the fusion proteins in vivo, depending on the hormonal status of the subjects.We replaced ER with a mutant receptor (TmR) which specifically binds to 4‐hydroxytamoxifen (Tm), to overcome limitations with wild‐type ER. Interleukin‐3 (IL‐3)‐dependent Ba/F3 cells and hematopoietic progenitor cells transduced with the resultant fusion proteins (GCRTmR and ΔGCRTmR) were examined for ligand‐inducible growth.GCRTmR‐ and ΔGCRTmR‐expressing Ba/F3 showed IL‐3‐independent growth in response to Tm, while the cells were unresponsive to estrogen at concentrations up to 10−7–10−6 M. Furthermore, murine bone marrow cells transduced with GCRTmR and ΔGCRTmR formed colonies in methylcellulose medium in response to Tm, while virtually no colonies appeared with 10−7 M estrogen or without cytokines.These results suggest that influences of the endogenous estrogen can be almost eliminated by using the GCRTmR/Tm or ΔGCRTmR/Tm system to expand gene‐modified hematopoietic stem/progenitor cells. Copyright © 1999 John Wiley & Sons, Ltd.

Magnetic characteristics were measured on stress-strain test pieces of non oriented 3 %SiFe with a magnetic measurement frame. Plotting various magnetic properties against plastic deformation shows an exponential damage for low and medium values of magnetic field amplitude. This phenomenon is much weaker when high magnetic field amplitudes are reached. Metallurgical state of the material between 0 and 0.5 % is characterized by the Luders strain state, which involves an important heterogeneous dislocations structure inside the metal die. After this, dislocation structure remains more and less homogeneous from 0 to 10 % strain (small tangles and isolated dislocations). These two dislocations structures are the more harmful for the magnetic properties of the alloys. From ?p= 10 % to fracture, dislocations configuration becomes progressively inhomogencous and walls of high density are created but any supplementary magnetic damage is observed. Potential theories are not able to explain our experimental results but domain wall bowing theories could successfully be applied. Coercive field versus plastic stress displays two distinct linear evolutions against three in the case of polycristalline high-purity iron, as shown by others authors. L'?volution des propri?t?s magn?tiques d'alliages Fe-3 %Si ? grains non orient?s avec les d?formations plastiques a ?t? ?valu?e ? l'aide d'une technique exp?rimentale permettant des mesures directes sur ?prouvettes de traction. Une d?gradation importante de ces caract?ristiques est observ?e aux faibles et moyennes amplitudes d'excitation magn?tique. Cet effet s'estompe pour les valeurs les plus ?lev?es du champ magn?tique. A mesure qu'augmente la d?formation, les dislocations s'organisent en cellules quasi hexagonales sur le palier de Luders, puis, en d?but d'?crouissage, se regroupent en petits amas faiblement denses s?parant des zones de m?tal o? existent des dislocations isol?es. Ces deux configurations sont les plus nocives pour les propri?t?s magn?tiques. Aux fortes d?formations, des murs de dislocations tr?s denses se forment, mais ne d?gradent pas davantage les caract?ristiques magn?tiques. Nous montrons que le mod?le du potentiel conservatif ne s'applique pas ? nos r?sultats exp?rimentaux tandis que celui de courbure des parois pourrait ?tre mieux adapt?. L'?volution du champ coercitif avec la contrainte plastique pure appliqu?e au mat?riau suit une loi en deux stades, contrairement aux trois stades obtenus sur du Fe polycristallin de haute puret? par d'autres auteurs.

Most motors for electric vehicles are based on the DC machine, nevertheless, the brushless surface mounted permanent magnet AC machine seems to be a good alternative. The authors propose a method of design and a comparison of two types of brushless machine that takes into account the requirements for the propulsion of electric vehicles. Two types of AC machine are designed taking into account the limitations due to the limited voltage power supply in terms of the airgap magnetic field shape and the corresponding stator current waveforms. Finally, a very simple analytical optimal design is proposed and verified both by numerical simulations and prototypes realisation.

No abstract.

In the presence of an excess of triethylamine title compounds such as (III) can be produced in good yields by treating elemental phosphorus (I) with alcohols or thiols (II) and CCl4(in molar ratio 1:12:6) in dipolar‐aprotic solvents.