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The acidity constants of the reduced and oxidized species of ferrocenylphosphonic acids FcPO3H2, FcCH2PO3H2and fcPO3H22Fc η5-C5H5Feη5-C5H4, fc η5-C5H4Feη5-C5H4 in water have been evaluated by potentiometric, 31P NMR, and electrochemical methods. The oxidized forms are more acidic than the reduced ones. The interaction between the redox centre and the charged oxygen atoms of the phosphonate group is shown to be electrostatic. The maximum oxidation shift ΔEbetween the protonated and unprotonated species increases with the number of charges of the substrate and decreases with the increase of the distance between the ferrocenyl centre and the oxygen atoms of the phosphonate group. The structure of FcPO3Na2·5H2O is determined. The compound crystallizes in the monoclinic system. It is lamellar with an inorganic layer formed by tetramers Na4O14, the ferrocenyl groups occupying the interlamellar space.

Virtual reality offers new tools for human motion understanding. Several applications have been widely used in teleoperation, military training, driving and flying simulators, and so forth. We propose to test if virtual reality is a valid training tool for the game of handball. We focused on the duel between a handball goalkeeper and a thrower. To this end, we defined a pilot experiment divided into two steps: an experiment with real subjects and another one with virtual throwers. The throwers' motions were captured in order to animate their avatar in a reality center. In this paper, we focused on the evaluation of presence when a goalkeeper is confronting these avatars. To this end, we compared the goalkeeper's gestures in the real and in the virtual experiment to determine if virtual reality engendered the same movements for the same throw. Our results show that gestures did not differ between the real and virtual environment. As a consequence, we can say that the virtual environment offered enough realism to initiate natural gestures. Moreover, as in real games, we observed the goalkeeper's anticipation to allow us to use virtual reality in future work as a way to understand the goalkeeper and thrower interactions. The main originality of this work was to measure presence in a sporting application with new evaluation methods based on motion capture.

The hybrid organic−inorganic phosphonate Al(μ-OH)(O3PCH2C6H4COOH)·H2O has been structurally characterized by comparison of its polarized ATR-FTIR spectra, MAS NMR, and TGA analysis with those of Al(μ-OH)(O3PCH2C6H4Br)·H2O and Al(μ-OH)(O3PCH2C6H5)·H2O whose crystallographic structures are known. The polarized ATR (attenuated total reflection) IR study revealed the presence and orientation of selected bonds with respect to the sample holder. Moreover, for the three compounds, the polarized study allowed the identification of a symmetric CPO3 vibration mode around 1050 cm^-1; usually, regular FTIR study of solid-state metallic phosphonates does not permit such precise attribution in this region of the IR spectrum. Polarized ATR FTIR spectroscopy, along with solid-state MAS NMR spectroscopy, appeared to be a very efficient tool for obtaining structural information on such solid-state hybrid compounds exhibiting highly anisotropic crystallites shapes.

Thermal transformations of the well-known high spin manganese carboxylate cluster [Mn₁₂O₁₂(CH₃COO)₁₆(H₂O)₄]·4H₂O·2CH₃COOH have been studied in detail. Three steps in its thermal transformation have been observed with the successive formation of well-defined compounds. Upon heating at 403 K, acetic acid and water molecules located in inter-cluster void spaces are removed without significant modification of the structural packing and magnetic properties. Interestingly, the resulting material presents the remarkable property of being able to incorporate ammonia into its structure. Dramatic changes in the magnetic properties of this insertion compound have been observed and confirmed the first synthesis of a single-molecule magnet material by gas inclusion. Further heating at 513 K stabilizes the hausmannite Mn₃O₄ phase as indicated by X-ray diffraction, thermogravimetric analyses and magnetic measurements. Finally, heating of the compound above 573 K leads to a mixture of different manganese compounds, Mn₃O₄ and MnCO₃, previously observed in the decomposition of Mn(CH₃COO)₂·4H₂O.

P-Vinylbenzylphosphonic acid (2) was synthesized and crystallized in two phases A and B. The latter phase was easily converted into the former. Both phases were investigated by IR and solid-state ³¹P and ¹H NMR spectroscopy, and X-ray crystallography. The use of recently developed NMR methods has enabled us to increase the usually poor resolution of solid-state ¹H spectra. This gave additional insights on the proton environments. In particular, two dimensional 2D ¹H-³¹P heteronuclear correlation (HETCOR) experiments, incorporating a Lee–Golburg homonuclear decoupling scheme, allowed description of the mixture of phase A and B.

We report a new, non‐isotopic, immunoassay (CMIA) for chlortoluron, a pesticide of the phenylurea family. The novel feature of this assay is the use of metal carbonyl complexes as tracers and Fourier‐transform infrared (FT‐IR) spectroscopy as the detection method. We describe the synthesis of three tracers, derivatives of chlortoluron with an attached cyclopentadienyl manganese tricarbonyl moiety. Quantitative analysis of these tracers, by FT‐IR spectroscopy was performed by simple measurement of the absorbance peak at 2033 cm−1, characteristic of the νCOof the metal‐carbonyl unit. Immunoassays were carried out using the IgG fraction of rabbit antiserum. Standard curves obtained by CMIA for the three tracers showed the feasibility of this technique for chlortoluron assay. However, the IC50and IC90values obtained with the three tracers varied widely, with the long‐chain tracer 12 giving the most sensitive assay for chlortoluron, with an IC50value of 50 pmol (21 µg l−1) and an IC90of 6.5 pmol (2.7 µg l−1). Copyright © 2002 John Wiley & Sons, Ltd.

Synthesis and characterization of the first stable α,ω-bis(silanetriols) containing phenylene, biphenylene, α,ω-bis(phenylene)vinylene, α,ω-bis(phenylene)ethynylene, and α,ω-bis(phenylene)buta-1,3-diynylene organic bridging groups are described. They were obtained by controlled hydrolysis of the corresponding bis(trialkoxysilyl) precursors. An alternative route involving phase-transfer catalysis is also reported. These solids were organized as layers. The triol end groups formed hydrophilic layers, whereas the body of the sheets corresponded to hydrophobic layers. The distance between two neighboring hydrophilic layers was directly related to the length of the organic group; nevertheless, the packing was induced by the hydrogen-bond network.

The small, compact, robust, and nonpolar units of [CpM(CO)3] (M=Re, Tc) coupled with biomolecules may be considered as bioorganometallic entities of potential interest in the field of medicinal chemistry. However, the short half‐life of useful radionuclides (186Re t1/2=3.7 d, 188Re t1/2=16.8 h, 99mTc t1/2=6 h), the risks inherent in their use, and their cost have led chemists to search for novel synthetic strategies that allow the rapid introduction of the [CpM(CO)3] moiety as a late step in the course of synthesizing the target molecule. The present paper describes different strategies recently reported in the literature to tackle this problem.

Mantle temperature variation and plate spreading rate variation have been considered to be the two fundamental variables that determine the extent of mantle melting and ocean crust production. Along the length of a ∼200 km portion of the Mid-Atlantic Ridge (MAR) between the Oceanographer (35°N) and Hayes (33°N) transforms, the mantle potential temperature is the same, the plate spreading rate is the same, but the extent of mantle melting and crustal production vary drastically. In addition to the typical crustal thickness variation on ridge segment scales at the MAR, i.e. thicker at segment centers and thinner at segment ends, there exist between-segment differences. For example, the ∼90 km long segment OH-1 is magmatically robust with a central topographic high, thick crust, and a large negative gravity anomaly whereas the ∼45 km long segment OH-3 is magmatically starved with a deep rift valley, thin crust and a weak negative gravity anomaly. We demonstrate that the observed differences in the extent of mantle melting, melt production and crustal mass between segments OH-1 and OH-3 are ultimately controlled by their fertile mantle source compositional difference as reflected by the lava compositional differences between the two segments: >70% of OH-1 samples studied (N=57) are enriched MORB with [La/Sm]N>1, but >85% of OH-3 samples studied (N=42) are depleted MORB with [La/Sm]N<1. Calculations show that the mean OH-1 source is more enriched in incompatible elements, total alkalis (∼0.36 wt% Na2O and ∼0.09% K2O) and H2O content (∼280 ppm) than the mean OH-3 source, which is depleted of incompatible elements, total alkalis (<0.17% Na2O and <0.01% K2O) and H2O content (∼70 ppm). These fertile compositional differences result in significantly reduced solidus temperature of OH-1 source over that of OH-3 source, and allows melting to begin at a significantly greater depth beneath OH-1 (∼90 km) than beneath OH-3 (<60 km), leading to a taller melting column, higher degrees of decompression melting, greater melt production, thus thicker crust and more negative gravity anomaly at OH-1 than at OH-3. We emphasize that fertile mantle source compositional variation is as important as mantle temperature variation and plate spreading rate variation in governing the extent of mantle melting, crustal production, and MORB chemistry. The buoyancy-driven focused mantle upwelling model better explains the observations than the subcrustal melt migration model. Future mantle flow models that consider the effect of fertile mantle compositional variation are expected to succeed in producing along-axis wavelengths of buoyant flow comparable to the observed size of ridge segments at the MAR. We propose that the size and fertility of the enriched mantle heterogeneities may actually control the initiation and evolution of ridge segments bounded by non-rigid discontinuities at slow-spreading ridges.

No Abstract Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2000/z15394_s.pdf or from the author.

Photodissociation of phenylsilane was studied by EPR spectroscopy using N-benzylidene-tert-butylamine N-oxide (PBN) and bis(benzene)chromium (BBC) as spin trapping systems. Under controlled UV irradiation and in the presence of dioxygen, hydrogen spin adducts were detected. Conditions for the formation and stability of the adducts have been studied. A mechanism involving “inverted spin trapping” was propounded that implies photoactivation of the spin traps followed by the formation of the superoxide radical ion O₂^&z.rad;− and the abstraction of H⁻ from phenylsilane.

Reaction of phosphonic acids RPO(OH)₂ (R = phenyl, benzyl, 4-bromobenzyl) with aluminium nitrate and sulfate under various hydrothermal conditions led to three novel aluminium phosphonates, Al(OH)(O₃PCH₂C₆H₄Br)·H₂O, Al(OH)(O₃PCH₂C₆H₅)·H₂O and Al₂(O₃PC₆H₅)₃·H₂O. All the compounds were characterised by powder XRD, elemental analysis, TGA, ²⁷Al and ³¹P MAS NMR and IR spectroscopy. The same tools were used to study the dehydration–rehydration reactions. Refinement of the structure of Al(OH)(O₃PCH₂C₆H₄Br)·H₂O by the Rietveld method showed a lamellar arrangement similar to the methyl analogue ζ-Al(OH)(O₃PCH₃)·H₂O. Al(OH)(O₃PCH₂C₆H₄Br)·H₂O crystallises in the monoclinic system, space group P2₁/c with unit cell parameters a = 16.4972(2) Å, b = 7.0673(1) Å, c = 9.4950(2) Å and β = 113.477(1)°. Based on the powder XRD, IR and NMR data the two benzyl compounds were found to be isostructural.

Submersible observations and sampling were carried out in the rift valley of the Mid-Atlantic Ridge (MAR) near 34°40′N–35°N. The 4-km-wide rift valley consists of a Neo Volcanic Zone (NVZ) (<1km wide) bounded at the west by a Median Ridge (MR) (5km wide and 20km long) and at the east by the first scarps of the eastern wall. The MR and the eastern wall are characterized by volcanic cones about 200–300m height culminating at depths of 1500–1900m which are made up of volcaniclastic deposits (pyroclasts and hyaloclasts) suggestive of explosive volcanism. Based on their surface morphology, degree of vesicularity, and composition, the erupted deposits are classified into four groups: (1) poorly vesicular (<15% vesicles) N- and T-MORBs (K/Ti <0.25, Na2O+K2O<2.9%) consisting of sheet flows and pillows formed during fissure eruptions in the NVZ at 2000–2300m depths; (2) vesicular (15–30% vesicles) E-MORBs (K/Ti=0.25−0.45,Na2O+K2O>2.8−3.2%)and alkali basalts (K/Ti=0.45−0.70,Na2O+K2O>3.3−4)made up mainly of pillows; (3) highly vesicular (>35% vesicles) pillow lava and pyroclastic (scoria-like) alkali basalts (K/Ti>0.45−0.80,Na2O+K2O>3−4%); and (4) hyaloclastites consisting of glassy shards of alkali basalt composition. The total water and carbon contents of the deposits increase with the incompatible element concentrations. The estimated initial H2O content for the N- and T-MORBs is less than 3500ppm, whereas for the E-MORBs and alkali basalts the H2O content is near 4000 and 7000ppm, respectively. While the H2O is mainly in the melt, the carbon is in the form of CO2filling vesicles. The vesicles are formed from magma with an initial carbon content of 1000–3000 for the N- and T-MORBs, 3000–6500ppm for the E-MORBs and higher than 1wt% for the alkali basalts.

A series of 2,4-di-arylated tropane derivatives was synthesized through a site-selective palladium-catalyzed β-C(sp3)–H di-arylation process. This type of structure has been scarcely reported in literature. They nevertheless represent an interesting class of biologically relevant molecules as illustrated by the observed activity at the micromolecular level of eight derivatives toward human colorectal cancer cell line HCT116.

An important concentration of patients with Rendu-Osler disease occurs in the Valserine valley of the French Jura. A study of marriages shows that, in spite of its somewhat remote location, the valley cannot be considered an isolate, but that, on the contrary, exogamy is widely practised. Only 17·8% of the genes of inhabitants during the present century can be traced to the original population, but persons affected with the disease belong to a subgroup of the population which has lived in the villages for more than 10 generations. All the patients in 85 sibships are related. The smallest number of originator couples who lived at the beginning of the eighteenth century amounts to 16, the unique originator may therefore have lived approximately four generations earlier. However, as other patients who lived at the periphery of the Valserine valley do not appear to be related to any patients living in the valley, and because there has been considerable immigration into the valley, a number of hypotheses to explain the distribution of the disease in the region remain possible.

Bromonitromethane, triethyl orthoformate and aniline react together, in a one-flask procedure, to afford the title compound.

The photo-oxidation of propionic acid by oxygen in aqueous solution has been studied in the presence of TiO2and dissolved copper ions as catalyst. The kinetics results agree with a “rake scheme” which involves acetic acid as an intermediate between propionic acid and the final product CO2. The role in this scheme of carboxylato complexes of copper both in the dissolved state and in the adsorbed state is stressed.

To study inheritance, it is necessary in the first place to know the number of heirs in each family, how property was divided between them, and whether their inheritance was sufficient to enable them to maintain and support several children in the parish. This study examines the process by which the populations of the parishes of the Valserine Valley in France reproduce themselves from one generation to the next, by means of examining the “effective” progeny of couples to determine how many of them produce children (heirs) who continue to live in the Valley. The ultimate goal of these researches is to establish the characteristics of those who leave the Valley, and how these differ from those who choose to stay. The article examines whether it is possible to discern a family strategy in the way these decisions are made, and whether behavior of the persons in question is determined by individual choice.

A specific interaction between psoralen and pyrimidine bases (thymine), revealed in crystals of compound III, induced under UV light a topochemical photocycloaddition between the double bonds of thymine and pyrone ring of psoralen. The crystallographic analysis of compound I, II and III demonstrated the minor perturbation displayed by the trioxyethylene chain on the chromophore packing modes.

The title compound crystallizes with four molecules in the asymmetric unit. They adopt a slightly bent conformation with quite extended perfluorinated aliphatic chain. The molecular arrangement is characterized by the segregation of the cores 4-cyanophenyl 4-benzoate on one side and the perfluorinated aliphatic chains on the other side. The molecules give bilayer sheets, parallel to the xoy plane, the thickness of bilayers being equal to the c parameter. The interactions between the sheets are quite weak.

The crystal structure of a biforked mesogen, exhibiting nematic and smectic phases, derived from 3,4-dialkyloxyphenyl cinnamic acid has been determined by direct methods. The crystal belongs to the P21/c space group (Z = 4): a = 42.380(7), b = 9.605(2), c = 18.12(1) Å, β = 97.93(2)°. Least squares refinement leads to R = 0.091.The molecules adopt a zig-zag form and the non-aliphatic central core is almost linear, and 35 Å long. The four alkyloxy chains are stretched (ttt). The mean axis of the alkyloxy chains makes an angle close to 130° with the central core. The molecules make sheets of abour 43 Å thick and are arranged as in a smectic C mesophase. The polyaromatic central core makes an angle close to 70° (tilt angle) with the normal to the sheet and is quasi-parallel to the (xz) plane. The interactions between the sheets are very weak. The structure is compared to those of similar compounds whose structure has recently been published.

Ketenes have been found to cycloadd with ( R)-2- tert-Butyldihydrooxazole 1and 2to yield predominantly regioisomers 4resulting from steric control rather than electronic control. The cycloadditions provide a practical route to enantiomerically pure protected 2-amino-3-hydroxycyclobutanones.

To study the influence of sea waves on the irradiance received on a detector situated beneath the sea surface, we used a Monte Carlo simulation. The influence of wind speed on the directly transmitted and scattered light is shown. The comparison between these two mechanisms of energy transmission indicates the essential contribution of scattering.

We describe a two-dimensional mosaic obtained by the Voronoi tesselation of a monosize assembly of discs at different packing fractions. The experimental device (hard discs moving on an air table) produces, for every concentration of the discs, a succession of mosaics in statistical equilibrium, which constitutes a statistical ensemble. This ensemble is large enough for fluctuations from the most probable distributions to be negligible. Both topological and metric properties show deviations from those of a totally random mosaic. These deviations can be ascribed to steric exclusions. In particular, distributions of the numbers of sides, of the perimeters and of the areas of the polygons differ from those observed in biological celi assemblies. The Aboav law holds, but with a slope which can be as Iow as 4-66. The Lewis law is obeyed only for smali packing fractions. The variance of the distribution of the number n of polygon sides is a universal function of p6, the probability of finding a six-sided polygon in the assembly.

A large variety of rocks, consisting of basalts, dolerites, gabbros and ultramafics, are exposed on the Intra-rift ridge in the Hess Deep, representing a section of the oceanic crust formed at the East Pacific Ridge [1]. We conducted a stable isotope study of O and H to assess the nature of the interaction between seawater and the oceanic crust in this region.

Fourteen dives of the submersible Nautile have been carried out at the eastern intersection of the Vema Fracture Zone with the Mid-Atlantic Ridge. Direct observations allow us to locate precisely the surficial expression of the transform fault motion in the southern trough of the fracture zone valley. The present-day displacement zone, corresponding to an extremely narrow (less than 300 m) transform fault zone, is confined to a belt of disturbed terrain situated at the foot of the southern wall and characterized by transform-parallel 30–100 m high ridges of basaltic fragments and pelagic sediments. Active splays of the transform fault zone lie generally between these ridges, creating steep V-shaped furrows. Despite a rather sinuous trend one of the fault strands appears to be laterally continuous and other minor active splays branch out from it or run parallel to it. The surface manifestations of the tectonic activity along the present-day displacement zone include (R) Riedel shears, low-angle shears, P shears, “en échelon” structures, open fissures, small pull-apart structures and funnel alignments in the sedimentary cover. The transform fault motion reactivates large normal faults on the adjacent flanks of the southern wall and the median ridge. The transform-parallel topography defines a 10 km wide zone with dip-slip motion. The ridge-transform intersection area is entirely floored by fresh basalts contrasting with other intersections of major fracture zones such as the Kane and Oceanographer Fracture Zones. Recent volcanic activity is not restricted to the central volcanic ridge but is widespread across the whole nodal basin area. The present-day displacement zone cross-cuts the neovolcanic zone, and the disconnected northernmost extension of the volcanic ridge is attached to the median ridge and so belongs to the African Plate. The extensive volcanism is suggestive of a magmatic production phase in the intersection area. Extremely fresh pillowed lava forms have been observed at the RTI inside-corner high, indicating possible off-axis volcanism.

Photocatalytic activity of TiO2 in the oxidation by oxygen of formic acid is considerably enhanced by the presence of dissolved copper ions. The role of oxygen transfer between the gas phase and the slurry is examined. The kinetic results obtained in the absence of mass transfer limitations lead to a mechanism based upon a redox cycle between Cu2+ and Cu+ species adsorbed on the surface of TiO2.

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One phasmid and fourteen biforked mesogens with thiobenzoate end groups have been synthesized and studied. The phasmid displays a hexagonal columnar phase with a lattice parameter a = 45.5 Å at 70°C. This phase is not observed for the biforked mesogens which exhibit only a nematic phase, a smectic C phase for short chains and an unknown phase for long chains. The tilt angle of the molecules in the smectic C phase is about 50° (the layer thickness is 38.2 Å for a molecular length l = 61 Å in the case of IA (n = 12). The crystal structure of compound IB (n = 12) is monoclinic and the molecules adopt a zigzag form.

The crystal structure of a biforked mesogen derived from 3,4-dialkyloxyphenyl propanoic acid is described. The molecule crystallizes in the P21/c space group with two molecules per unit cell: a = 50·740 (3), b = 8·425 (2), c = 9·250 (1)Å and β = 91·340 (7)˚; the final reliability factor is R = 0·086. Molecules adopt a zig-zag form: the non-aliphatic central moiety is 36·2 A long; the two alkyloxy chains are stretched (ttt) and are approximately parallel to the xy plane; both chains make an angle close to 120° with the central moiety. Molecules make sheets of about 51 Å thickness; the polyaromatic central core makes an angle close to 60° (tilt angle) with the normal to the sheet and is quasi-parallel to the xy plane; interactions between sheets are very weak. Here, we try to given an explanation of the transition between the crystalline arrangement of molecules and the hexagonal symmetry of the mesophase for this compound.

Q fever, caused by Coxiella burnetii, is a worldwide zoonotic disease that may cause severe forms in humans and requires a specific and prolonged antibiotic treatment. Although current serological and molecular detection tools allow a reliable diagnosis of the disease, culture of C. burnetiistrains is mandatory to assess their susceptibility to antibiotics and sequence their genome in order to optimize patient management and epidemiological studies. However, cultivating this fastidious microorganism is difficult and restricted to reference centers, as it requires biosafety level 3 laboratories and relies on cell culture performed by experienced technicians.

The confinement of ionic liquids within a porous silica matrix was performed by a one-step non-hydrolytic sol-gel route, leading to hybrid materials called “ionogels” featuring both the mechanical and transparency properties of silica gels and the high ionic conductivity and thermal stability of ionic liquids.