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In the context of the verification regime of the Comprehensive nuclear Test ban Treaty (CTBT), CEA is developing a new generation (NG) of SPALAX™ system for atmospheric radioxenon monitoring. These systems are able to extract more than 6cm(3) of pure xenon from air samples each 12h and to measure the four relevant xenon radioactive isotopes using a high resolution detection system operating in electron-photon coincidence mode. This paper presents the performances of the SPALAX™ NG prototype in operation at Bruyères-le-Châtel CEA centre, integrating the most recent CEA developments. It especially focuses on an innovative detection system made up of a gas cell equipped with two face-to-face silicon detectors associated to one or two germanium detectors. Minimum Detectable activity Concentrations (MDCs) of environmental samples were calculated to be approximately 0.1 mBq/m(3) for the isotopes (131m)Xe, (133m)Xe, (133)Xe and 0.4 mBq/m(3) for (135)Xe (single germanium configuration). The detection system might be used to simultaneously measure particulate and noble gas samples from the CTBT International Monitoring System (IMS). That possibility could lead to new capacities for particulate measurements by allowing electron-photon coincidence detection of certain fission products.

Radioactive xenon (mainly 131m Xe, 133 Xe, 133m Xe and 135 Xe) are tracked as markers of nuclear weapons testing. The CEA has developed the PIPSBox, a measurement cell able to detect electrons emitted by xenon nuclides. Combined with an ultra-low background γ spectrometer, electron detection capacities allow reaching minimum detectable activities (MDA) for a 3-day long measurement of about 0.5 mBq for the four xenon radionuclides. Compared to a classical measurement cell, MDAs are improved by a factor of 2–4.

Poursuivant leurs recherches sur la chimie des acides gras α, α-disubstitues les auteurs decrivent dans le present travail une serie de representants nouveaux de cette famille de substances. II est montre en outre que les amides des acides gras α, α-dimethyles ne peuvent etre saponifies par la potasse alcoolique que lorsqu'ils renferment une double liaison dans leur molecule.

On decrit dans le present memoire la preparation et les principales proprietes de 2 phenanthrenes substituees par le radical quinoleiqe.

Dans le cadre de l'etude de l'action des reactifs nucleophiles sur les perchlorates de selenopyrylium, nous decrivons la synthese des perchlorates de 1-benzothieno (3,2-b) et (2,3-b) selenopyrylium. Ces composes relativement stables ont ete caracterises notamment par leurs spectres de RMN et UV. Leur reactivite sera decrite ulterieurement.

Several samples of exhaust diesel soot are investigated by inverse gas chromatography and linear solvation energy relationship (LSER) modelling according to their soluble organic fraction content and their time of exposure in oxidative conditions. The results demonstrate the evolution of the adsorptive properties of the studied materials towards volatile compounds during the oxidation under NO 2 .

The preparation of active carbons from nitrogen-enriched lignites was previously described by the authors. This study is carried on with the aim of investigating the role played by the mineral matters of lignites on the process and on the properties of the resulting active carbons. First, the effect of demineralisation by strong acids on the surface chemical properties of the lignite sample was studied. The XRD and FT-IR analysis showed that carbonates (calcite, dolomite) are totally removed, and the main remaining mineral matter constituents are well crystallized quartz besides a small amount of sulphates (bassanite). The changes in the surface chemistry properties were investigated by FT-IR spectroscopy, Boehm's titration method and LSER modelling. All these methods pointed out the increase of the acidic character of the surface of the lignite after demineralisation.

Two samples of soot are studied in the present work. The results obtained on a virgin diesel soot (VDS) are compared to those obtained on the corresponding material after removal of its soluble organic fraction (SOF). The adsorption properties of both materials towards organic compounds are investigated by gas chromatography (GC) using the linear solvation energy relationship (LSER) equation of Abraham [Chem Soc Rev 1993;22:73–83]. This approach allows each material to be characterized in terms of five quantitative molecular interaction parameters. The results show the large influence of the SOF in the adsorption process of gaseous organic compounds. This study reveals that the extracted diesel soot (EDS) can interact through molecular interactions similar to those obtained on fullerenes or graphite.

Pure samples of (131m)Xe, (133m)Xe, (133)Xe and (135)Xe facilitate the calibration and testing of noble gas sampler stations and related laboratory instrumentation. We have earlier reported a Penning trap-based production method for pure (133m)Xe and (133)Xe samples. Here we complete the work by reporting the successful production of pure (131m)Xe and (135)Xe samples using the same technique. In addition, we present data on xenon release from graphite.

One investigated way to prepare selective adsorbents towards mixtures of volatile organic compounds (VOCs) is to modify lignite by nitrogen-enrichment. These chemically modified coals are prepared by condensation of urea with the lignite before the carbonization/activation steps. This study describes a set of analytical tools able to explain in term of surface composition and of quantitative molecular interaction parameters the evolution of the selective behavior of three adsorbents. For this purpose, the evolution of the surface chemistry and the selectivity with three percentage of burn-off of a nitrogen-enriched lignite is followed by infrared and X-ray photoelectron spectroscopies and gas chromatography (GC)/linear solvation energy relationship (LSER) method. Then, the selectivity of these materials towards two test-pairs of VOCs is discussed. This QSBR investigation reveals the complementarity of these methods linking composition data of the active carbons and their selective properties.

The preparation of active carbons containing nitrogen surface functions is considered by ammoxidation of various raw materials like pinewood, peat and lignite. To have an accurate knowledge of the nitrogen functions introduced, diffuse reflectance IR/FT and X-ray photoelectron spectroscopies were used. Taking into account the complexity of the raw materials, the structural characterisation of the cellulose ammoxidation products was undertaken in the first step of our study, since cellulose is one of the major compounds of woods. The thermal treatment of cellulose, at around 250 °C and at different durations (1, 2, 4 h), was realised for comparison under several conditions: air, argon, ammonia and air–ammonia mixtures (ammoxidation). Several nitrogenated structures were characterised. The mechanism of their formation from the C4 fragment formed from the heterolytic cleavage of cellulose by thermal treatment was proposed pointing out the fundamental role of intermediate imine function.

The aim of this work is to study the efficiency of the nitrogen enrichment by urea of lignites and the induced changes of the adsorptive properties towards volatile organic compounds (VOCs) of the activated carbons derived from these modified precursors. The study is made using infrared and X-ray photoelectrons spectroscopies and the LSER (linear solvation energy relationship) modeling. Four activated lignites derived from the same raw material, original or enriched with nitrogen, are characterized in this way. The effect of the chemical treatment by urea and of the burn-off amount are investigated in term of evolution of the chemistry of the studied materials. The influence of these parameters on the selective behavior of the activated lignites towards two pairs of VOCs is also discussed in terms of molecular interactions using the LSER approach. The results show that the chemical treatment of the raw material is successful, leading to significant enrichment with nitrogen under pyridinic form at the surface of the activated carbons. Moreover, they reveal some selective properties well explained by the LSER analysis and spectroscopic measurements. The selective character of the studied materials is modulated by the duration of the activation step.

The reductive alkylation of a French petroleum asphaltene (Lagrave) was studied with potassium in THF, in absence of an electron transfer reagent. From the number of butyl and benzyl groups added to the starting asphaltene, the difference of reactivity of the alkyl reagents, butyl iodide and benzyl bromide, was pointed out. Special attention was focused on the cleavage of C–S and C–O linkages in relation to the structural modifications. From the number of hydrogen atoms added during the reduction step, it was concluded that the sulphide linkages are mainly of aryl-S-aryl, aryl-S-alkyl or alkyl-S-alkyl types. The TLC-FID (Iatroscan) analysis was found to be very suitable to follow the “depolymerization” process of the asphaltene, qualitatively as well as quantitatively, by the application of quantitative hydrocarbon group type analysis.

(127)Xe has a longer half-life than (131m)Xe, it can be easily purely produced and it is present in the environment at very low level. For these reasons, (127)Xe is supposed to be a convenient quality control radionuclide for remote noble gas stations of the International Monitoring System (IMS) network. As CEA/DAM has recently developed two new photon/electron setups for low-level detection of (131m)Xe, (133m)Xe, (133)Xe and (135)Xe, we took the opportunity to test these setups for the measurement of a (127)Xe standard. The results and a detailed description of these measurements are presented in this paper. They illustrate the complexity of (127)Xe decay, emitting simultaneously several γ, X-rays, conversion electrons and Auger electrons; this results in highly summated coincidence spectra. The measurements performed provide precise electron energy calibration of the setups. The count rate of electrons in coincidence with iodine Kα X-rays was found to be surprisingly low, leading to the study of electron-gated photon spectrum. Finally, a comparison of three photon/electron coincidence spectra obtained with three different setups is given. The use of (127)Xe as a standard for energy calibration of IMS noble gas station is possible, but it appears to be quite complicated for efficiency check of noble gas station equipped with β/γ detectors.

The modifications afforded by several chemical treatments to the main functional groups of a bituminous coal were characterized by diffuse reflectance infrared spectroscopy. The starting materials were the polyanions and potassium coal adducts obtained from the parent coal, treated with potassium according to the Sternberg and Lazarov reactions. The results show the differences in the reactive sites involved in these reactions and in the behaviour of these sites during protonation or alkylation. Some of the typical functional groups introduced (or modified) can be active acceptor sites during hydrogen transfer from tetralin at low temperature (315°C) in conditions avoiding thermal bond cleavage. Taking into account the semiquantitative results of the i.r. analysis, the participation of several active sites in the total hydrogen transfer was estimated, indicating the role of quinonic, aromatic and alkyl groups.

Previous experiments carried out on several carbonization phases showed a relationship between tar migration and the coking pressure. In the present study, tests analogous in principle to the previous ones were conducted at a pilot scale with 400 kg coal charges. Two coals were used: C28, which leads to no pressure (“safe”), and C19, which induces pressure (“dangerous”). N-methyl-2-pyrrolidinone (NMP) extractions from the carbonization phases of the two coals confirm that tar migration is dependent on the nature of the parent coal, i.e. whether “safe” or “dangerous”. In the case of dangerous coal, the impregnation of non-coked coal by tars has been evidenced. In relation to this phenomenon, increased coking pressure is likely to develop due to the enrichment of non-transformed coal by volatile matter, as well as to the drop in permeability of this phase. It is also suggested that heavy tars clog up the pores of the semi-coke of dangerous coals.

Previous experiments carried out on several carbonization phases at laboratory and pilot scales have shown a relationship between the migration of tar, evidenced by extraction with N -methyl-2-pyrrolidinone (NMP), and the coking pressure. In the present study, complementary experiments using similar analytical techniques confirm that the impregnation of non-transformed coal by recondensed tars is related to the wall pressure that develops during pyrolysis. The results obtained on partially coked coal charges in a laboratory oven permit the simulation of the evolution of impregnation versus the blending ratio of binary blends. Compared with pilot-scale measurements of the wall pressure on various blends, this evolution of impregnation appears to be directly related to the wall pressure. On this basis, a predictive laboratory test of wall pressure evaluation through solvent extraction is proposed.

During the coking process, the production of volatile matters, in the plastic phase of the coking charge, leads to the development of dangerous internal pressures if hindrance is encountered in the gas release. By withdrawing and quenching coking coal charges at a given temperature in the course of heating, several phases of carbonization were isolated and submitted to physicochemical analyses: diffuse reflectance infrared spectroscopy (DRIFT), proximate and ultimate analysis, N-methyl-2-pyrrolidinone (NMP) extraction and hydrogen transfer (HT). By these means, two distinct ways of migration of volatile matters through coking material were evidenced. For ‘dangerous coals’ (including excessive coking pressure) the volatile materials migrate mainly from the plastic layer to the cold side of the oven, giving rise to impregnation of the remaining coal. On the contrary, a large part of volatile components of ‘safe’ coals migrate towards the hot side of the oven through semi-coke and coke. These results are in agreement with our preliminary study on the variations of the permeability of the different phases of carbonization.

The rheological behaviour of a Donbass bituminous coal was characterized by thermomechanical analysis under high pressure (6 MPa) from ambient temperature up to 600°C. Under these conditions the onset of the transfer of the coal from a viscous to a viscofluid state could be determined from the thermomechanical curves in a range of temperature not easily accessible with classical plastometers. The softening temperature and the activation energy of the viscous flow could also be determined. As intramolecular interactions are principally involved in the first stage of the thermoplasticity of coals, chemical modifications were applied to the coal by reductive alkylation and oxidation under several conditions (Sternberg and Lazarov reactions) to modify the intermolecular association. The influence of these treatments is clearly shown by the thermomechanical analysis.

Vitrain from a bituminous coal was modified by selective chemical reaction to reveal particular structural characteristics of the organic matter responsible for the change in conversion during solubilization by methanol-NaOH treatment (M treatment). The selective reactions were alkylating and non-alkylating reduction according to Sternberg, performic acid oxidation, thermal decarboxylation of the oxidized vitrain, LiAlH 4 reduction of the oxidized vitrain and O-methylation of the residual hydroxyl groups. The products of M treatment were pyrolysed in a stream of helium at atmospheric pressure, and the volatile compounds were continuously detected by flame ionization or mass spectrometry. The changes in structure and reactivity during M treatment were assessed by comparing gas evolution during programmed pyrolysis of the M product with that of the initial vitrain and its modified by-products. The M treatment strongly increased the pyrolytic conversion, and correspondingly reduced the formation of molecular hydrogen during secondary pyrolysis. The methylation of aromatic systems in the coal by M treatment is a main component of this process. The oxidized vitrain and its oxidized products show the highest conversion, indicating the critical role of hydrogenation in bond-breaking and in prevention of regressive reactions during M treatment. Pre-oxidation and LiAlH 4 reduction enhance denitrogenation of the coal during M treatment and subsequent pyrolysis.

Analysis by Fourier transform infrared (FT-i.r.) spectroscopy of coals and their extraction products, i.e. extracts and residues, gives an insight into the chemical structure of the initial material and changes due to the separation procedure. High quality spectra are obtained for solids by diffuse reflectance FT-i.r. spectroscopy. They also provide rather broad overlapping bands which have to be manipulated to supply useful information. It is shown that Fourier self-deconvolution improves the qualitative and semi quantitative analysis of FT-i.r. spectra of the coals and their N -methyl 2-pyrrolidinone (NMP) extraction products. Several samples of coals (rank ranging from C (wt%, daf) 85.6 to 92.4) were studied. Four spectral regions were selected for discussion: 3100-2800 cm −1 ν(CH ar ), ν(CH ali ); 1750-1600 cm −1 ν(CO), ν(CC ar ); 1260-1034 cm −1 ν(CO); 900-650 cm −1 γ(CH ar ). Several ratios were calculated, including: [ν(CH ar )/ν(CH 2 ,CH 3 )], [ν(CO)/ν(CC)], [ν(CO)/ν(CC)], [γ(CH)(1H)/Σγ(CH)], [γ(CH)(2,3H)/Σγ(CH)] and [γ(CH)(4H)/Σγ(CH)]. These data led to a comparison of the structural characteristics of the coals and of their extraction products. In each case the results are discussed in relation to the various trends observed in the samples, the possible relations with Gieseler fluidity of coals and the sizes of molecular orientations in the relevant cokes obtained by pyrolysis at 1000°C.

13 C solid-state n.m.r. was used to characterize three Polish coals and their solvolysis products. Analyses of protonated and non-protonated proportions were performed with dipolar dephasing and similar methods. Mobile phases were analysed through proton T 1 ρH measurements. The relation between aromaticity factor and H C atomic ratio is discussed.

Several chemical treatments were applied to a vitrain sample. It is assumed that structural modifications play an important role in subsequent solubilization by a methanol-NaOH mixture. The gradual changes of the main functional groups after chemical pretreatment and solubilization reaction were examined by Fourier transform infrared (FT-i.r.) and diffuse reflectance infrared (DRIFT) spectroscopy. The influence of the structural changes on the behaviour of the samples in solvent extraction (conversion) has been studied by sonication experiments, carried out before and after pretreatment and solubilization reaction.

To explain certain phenomena occurring during thermal processing of coal, studies were made of hydrogen transfer to coals, their N -methyl-2-pyrrolidinone (NMP) extracts and residues and tetrahydrofuran (THF)-soluble and -insoluble parts of the NMP extracts. The transfer of hydrogen to coals was found to be rank-dependent; the extraction products followed the same trend but with a poorer correlation. Much higher hydrogen acceptance reactivities were determined for NMP residues than for parent coals. The reactivity of extracts changed during prolonged storage. The FT-i.r. deconvoluted spectra, the correlation between oxygen content and hydrogen transfer and other data indicated that carbonyl (quinone) groups are the primary acceptor sites of hydrogen from tetralin at relatively low temperature (310–320 °C). The relation between hydrogen acceptance and coke microtexture formation during carbonization is discussed.

Vitrain from Debiensko bituminous coal was modified by selective chemical reaction to reveal particular structural characteristics of organic matter responsible for the improved or worsened conversion during the solubilization of coal by methanol-NaOH treatment. The selective reactions were: alkylating and non-alkylating reduction according to Sternberg, performic acid oxidation, thermal decarboxylation of the oxidized vitrain, LiAlH4 reduction of the oxidized vitrain and O-methylation of residual hydroxyl groups. The original vitrain and the products of the modification reactions were pyrolysed in a stream of helium at atmospheric pressure and the volatile compounds were continuously detected during thermal programming, using flame ionization detection or mass spectrometry. The compounds detected were: tar and light oils, CO2, CO, SO2, H2S, CH4, H2 and N2. The results are in agreement with the expected changes in chemical structure. A number of coal structural features are revealed by detailed examination of the gas profiles. Oil and gas evolution correlate well with infrared spectroscopy and sequential solvent extraction of the modified samples. The higher oil yield and the lower yields of H2 and N2 can be attributed to the suppression of the regressive effect of the oxygen groups and to the addition of hydrogen centres.

Catalytic hydroliquefactions (HL) of two coals (Freyming, France and Point of Ayr, United Kingdom) and their macerals were studied in a microautoclave in the presence of an H-donor solvent (tetralin). The main results of the study were related to (i) a comparison between the behaviours of such coals or macerals in the HL process; the two raw coals showed the same total conversion, and similar wt% of oil, asphaltene and preasphaltene fractions, (ii) the contribution of each maceral to the global coal liquid; the additive effect was checked, but no synergetic effect was found (using HL and the present type of liquid phase analysis) for a'synthetic coal'. Raw coals, vitrite and exinite had the same total conversion, whereas that for fusite was much lower, and (iii) a detailed identification of some individual compounds or of series of homologous compounds; this was made for oil fractions

The examination of the structural characteristics of the substances extracted from four coal samples, using N-methyl-2-pyrrolidinone, was carried out by pyrolysis-field ionization mass spectrometry (Py-FIMS). The extract are complex mixtures of relatively easily distillable component and of larger entities, supposed to be «oligomeric» parts of the coal structure, which are pyrolyzed above 400°C with the production of hydroxylated derivatives. Polycondensed structures predominate (4 to 7-8 nuclei) in a wide range of m/z values, mainly 250-350

The catalysts studied were aerosols of SiO 2 , Fe 2 O 3 , MoO 3 and Ni-Mo/Al 2 O 3 . The hydroliquefaction runs at 350, 400 and 430°C, in the presence of tetralin and sulfur, were evaluated by solvent extractions, hydrogen consumption and structural analysis of the isolated oil and asphaltene fractions. At 350°C, a clear influence of the catalyst on the extraction yields is observed. This effect disappears at higher temperatures. Nevertheless, hydrogen consumption from gas or solvent is affected by the nature of the catalyst at a given temperature. The influence of the catalyst is also confirmed by electron spin resonance study of the stable radicals of the tetrahydrofuran insoluble fractions. After elimination of tetralin, the structural analyses were carried out by gas chromatography (oils), size exclusion chromatography (oils and asphaltenes) and extrography (raw hydroliquefaction products). The oils obtained with sulfided Fe 2 O 3 or MoO 3 contained significantly more two-ringed aromatic compounds than oils obtained with the other catalysts or without added catalyst. No significant influence of the catalyst at a given temperature on the oils and asphaltenes is observed by size exclusion chromatography. In contrast, a large temperature effect is evidenced for each fraction, independently of the nature of the catalyst.

the solid state by means of 13C cross polarization/magic angle spinning n.m.r. and FT-i.r. spectroscopies. Several structural parameters derived from these analyses allow the characterization of the three macerals, vitrinite, exinite and fusinite, and their comparison with their parental coal. These structural data were compared with the solvent extraction yields of the same samples with N-methyl 2-pyrrolidone. (Keywords: characterization of coal; 13C n.m.r.; FT-i.r.) The characterization of Polish coal samples and their main macerals (vitrinite, exinite and fusinite) was investigated in the solid state by 13C cross polarization/ magic angle spinning (CP/MAS) n.m.r. and FT-i.r. spectroscopies. These two methods are particularly suit- able in the case of whole samples before any fractionation treatments. This study is related to solvolysis experiments carried out on the same coal samples' and macerals' by N-methyl 2-pyrrolidone extraction. The main objective, besides the establishment of parameters suitable for structural characterization, was to study the relation between the sample origin and the solvent extraction yields of the coals and their macerals. In addition to a semi-quantitative utilization of the n.m.r. spectra, more accurate results were obtained from dipolar dephasing experiments which gave the proportion of non-protonated aromatic carbons C" and the times of the decay of the aromatic protonated, TaP, and non-protonated, TaNP, carbons. From these parameters and others calculated from EN some characteristic features of the macerals can be inferred. Noteworthy, interesting relations were found between the size of the aromatic parts and the degree of alkylation of the macerals and their parent coals. On the other hand, considering the maceral composition of the coals and the parameters f, and c" of each coal and its macerals, additive relations were found which indicate the accuracy of the n.m.r. parameter determinations. In the same way, structural variations of these characteristics were followed from one coal to another. The 13C CP/MAS n.m.r. results were compared to those obtained by FT-i.r. spectroscopy. EXPERIMENTAL

Thermobalance hydropyrolysis experiments are carried out on a highly volatile coal sample and its main macerals, vitrinite and exinite. The results are discussed according to the characterization of the tars using ultrasound solvent extractions, extrography, liquid chromatography, capillary gas chromatography and mass spectrometry.

Hydroaromatics (partially hydrogenated polycyclic aromatic hydrocarbons) generated in the course of the process play an important role in the catalytic hydroliquefaction of coal. A difficult analytical task is to identify and to quantify these hydroaromatics among the preponderant polycyclic aromatic hydrocarbons. Generally speaking, the method carried out uses the specific separation of hydroaromatic by charge transfer chromatography. Structural identification is effected by using gas chromatography, alone or coupled with mass spectrometry, and HPLC on amino bonded phase with UV detection.

This study concerns the extractable materials obtained by solvolysis of three Polish coals. N-methyl-2-pyrrolidinone extraction and NaOH CH 3 OH treatment of these coals were compared using several analytical procedures (extrography, sonication, gas capillary column chromatography, and i.r. and 1H n.m.r. spectroscopy). Thermodesorption, on line with gas chromatography and mass spectrometry, was also applied to these coal samples.

Thermogravimetric analysis and differential scanning calorimetry were applied to the characterization of low and high temperature coal tar and petroleum pitches, and their fractions were separated by extrography. The main data concern Td values, and variations with the specific heat and glass transition temperatures of the pitch samples.

Les methyl-1[1]benzofuro, [1]benzothieno et[1]benzoselenolo [3,2-b]pyrrole de měme que les methyl-1[1]benzothieno et[1]benzoselenolo[2,3-b]pyrroles presentent une rectivite partagee entre leurs positions-2 et 3 vis-a-vis de la rection d'acetylation. La rection de lithiation n'affecte pas ou affecte tees peu les quatre premiers composes; quant au methyl-1[1]benzoselenolo[2,3-b]pyrrole, il subit une ouverture du cycle selenophenique et fournit apres carbonatation et esterification au diazomethane le methyl-1 methoxycarbonyl-2 o-methylselenophenyl-3 pyrrole. The influence of annelaction and of the heteroatom upon the reactity of some haterocyclic analogus of phenanthrene with a pyrrole nucleos was tested toward acetylation and lithiation. If methy-l[1]benzofuro-[3,2-b]pyrrole was acetylated only in the 2-position, the sulfer and selenious analogues with [3,2-b] and [2,3-b] annelarion were acetylated in the -2 and -3 position. No reaction at all or only with poor yield (in the oxygenated series) was observed with butyllithium except on the case of l-methyl[1]benzoselenono[2,3-b]pyrrole, where the opening of the selenophene nucleos gives, after carbonation and action of diazomethane, l-methyl-2-methoxycarbony 1-3-(o-methylselenophenyl) pyrrole.

La condensation du sarcosinate d'ethyle sur les halogeno-2 (ou -3) formyl-3 (ou -2) [l]benzofuranne, benzo-thiophene et benzoselenophene de měme que sur les 2H-[1]benzoheterocyclariones-3 correspondantes a ete etudiee. Dans ce dernier cas, le compose obtenu est ensuite formyle et cyclodeshydrate. Ont ete ainsi synthetises les methyl-l-[l]benzothieno, benzoseleno[2,3-b]pyrroles et les methyl-1-[1]benzofuro, benzothieno et benzoseleno[3,2-6]pyrroles. The condensation of ethyl sarcosinate on 2- or 3-halogeno 3- or 2-formyl[1]benzofuran. benzothiophene or benzoselenophene, and on the related 2h-[1]-3-benzoheteroyclanones is described. In the last instances the resulting compounds were formylated in teh 2-position with subsequent. After hydrolysis and decarboxylation, the I1methy][1]benzothieno-, benzoseleno [2,3-b]pyrroles were were thus obtained.

Resume Les auteurs etudient la cyclisation des acides ω-(indanyl-1) alcanoiques au moyen de l'acide polyphosphorique. Selon l'acide envisage on obtient un melange en proportions variables des cetones a annelation angulaire et lineaire.

Par application de la synthese de Fiesselmann, les auteurs decrivent la preparation d'amino-3 thiophenes substitues par des groupements aryles ou hetaryles. Applying Fiesselman's condensation to α-hydroxymethylene nitriles the authors describe a synthesis of substituted aminothiophenes.

A method of synthesis of ‘dimers’ of catechin and epicatechin is described which gives 50% yields of the pure substances. The structures of the products are confirmed by nuclear magnetic resonance using 1H and 13C resonances and by mass spectrometry. Mass spectrometry using laser impact with (+) ions allows a rapid distinction to be made between the ‘dimers’ derived from catechin or epicatechin.

The thermal treatments of coal tar and petroleum pitches, of their fractions obtained by extrography and of mixtures of these fractions, have been achieved at 350, 400 and 450 °C. Experimental results show the differentiation between low and high temperature pitches, and the influence of their chemical constituents on their thermal behaviour. The solvolytic or cross-linking action of some of them was pointed out.

A global characterization method for studying hydroxyaromatic compounds in coal liquids is presented. This method includes : short path distillation of crude sample, selective separation of hydroxyaromatic compounds on anion exchange resin, spectrometric analyses (1H and 19F NMR and mass spectrometry). From the different analytical results functional groups are determined which lead to a very convenient representation of the studied sample.

Treatment of nickel(II) tetrafluoroborate with some open-structured ligands of type 1,4,8,11-tetrathiaundecane (TTU) gives complexes which are characterised by laser microprobe mass analyses (LAMMA) and photoelectron spectroscopy (ESCA).

3-Substituted N-acetyl, N-ethoxycarbonylmethyl-2-aminothiophen derivatives are shown to exist in the endo (the amide carbonyl cis to the thiophen ring) and exo forms, the latter in predominant amount (92 to 98%). Proton nonequivalence reveals the absence of coplanarity between the thiophen and amide planes and the presence of two biphenyl-like enantiomers d and l. The barriers to rotation about the amide bond (Rx) and the aryl-to-nitrogen bond (RN) have been measured in three solvents: ΔG≠ (25°C) ∼ 71 and 54 kJ. mole−1, respectively. Competitive delocalisation of the nitrogen doublet to the amide group or to the thiophen ring is shown to account for structural and solvent effects upon the endo to exo molar ratio, the degree of chemical shift nonequivalence and the kinetic parameters of processes Rx and RN.