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ATP7A and ATP7B are structurally similar but functionally distinct active copper transporters that regulate copper levels in the human cells and deliver copper to the biosynthetic pathways. Both proteins have a chain of six cytosolic metal-binding domains (MBDs) believed to be involved in the copper-dependent regulation of the activity and intracellular localization of these enzymes. Although all the MBDs are quite similar in structure, their spacing differs markedly between ATP7A and ATP7B. We show by NMR that the long polypeptide between MBD1 and MBD2 of ATP7A forms an additional seventh metastable domain, which we called HMA1A (heavy metal associated domain 1A). The structure of HMA1A resembles the MBDs but contains no copper-binding site. The HMA1A domain, which is unique to ATP7A, may modulate regulatory interactions between MBD1–3, contributing to the distinct functional properties of ATP7A and ATP7B.

We report on the facile synthesis of porous carbons based on a biopolymer lignin employing a two-step process which includes the activation by KOH in various amounts under an inert gas atmosphere. The resulting carbons are characterized with regard to their structural properties and their electrochemical performance as an active material in double-layer capacitors using for the first time an ionic liquid (EMIBF4) as the electrolyte for this type of carbon material to enhance storage ability. A capacitance of more than 200 F g–1 at 10 A g–1 is achieved for a carbon with a specific surface area of more than 1800 m2 g–1. One of the most crucial factors determining the electrochemical response of the active materials was found to be the strong surface functionalization by oxygen-containing groups. Furthermore, the sulfur content of the carbon precursor lignin does not result in a significant amount of sulfur-containing surface functionalities which might interact with the electrolyte.

Spherical nanocrystalline TiH 2 powder was synthesized by calciothermic reduction of TiO 2 with CaH 2 at low temperature. Reduction was performed in solid state either by reactive milling in H 2 or via pre-milling in Ar with subsequent heat treatment in H 2 . Reactively milled powders are pyrophoric on exposure to air. Leaching of the side product CaO was only successful from the pre-milled and heat treated powders. As synthesized TiH 2 is stable in air and desorbs H 2 below 600 °C forming nanocrystalline Ti. Therefore it is suitable to prepare ultra finegrained cp-Ti.

Ethylene glycol-functionalized Co(II) carboxylates [Co(CO2CH2(OC2H4) n OMe)2] (2a, n = 1; 2b, n = 2), [Co(CO2CHPh(OC2H4)2OMe)2] (2c) and [Co(CO2CMe2(O–C2H4)2OMe)2] (2d) have been synthesized by the reaction of [Co(OAc)2·4H2O] with the corresponding acids MeO(C2H4O) n CRR′CO2H (n = 1, 2; R=H, R′=Me; R=H, R′=Ph). Based on the IR spectroscopic studies, the binding motif of the carboxylato ligands to cobalt is discussed. Thermogravimetry and mass spectrometry studies were carried out in order to investigate the thermal decomposition mechanism of 2a–2d in the solid state. Based on the result obtained, complex 2b was chosen as single-source precursor for the generation and stabilization of Co3O4 nanoparticles (NPs) by solid-state thermal decomposition in air. Depending on the decomposition time, NPs with different chemical composition (consisting of Co3O4, CoO and Co) and with crystallite sizes ranging from 9 to 18 nm were obtained. Furthermore, the preparation of cobalt oxide-based nanocomposites by twin polymerization of 2,2′-spirobi[4H-1,3,2-benzodioxasiline] (3) in the presence of 2b is reported. After treatment of the as-prepared hybrid material by either oxidation or etching, the respective mesoporous carbon/silica (IUPAC type IV isotherms) matrices were obtained. Quenched solid and nonlinear density functional theory calculations gave a surface area of 1040 cm2 g−1 for the respective carbon and 336 cm2 g−1 for the appropriate silica material. Powder X-ray diffraction measurements confirm the formation of Co3O4 NPs in both components. High-angle annular dark field scanning transmission electron microscopy revealed well-distributed particles within the silica matrix, whereas no particles were found in the carbon material. The electrochemical properties of the composite materials have been investigated by cyclic voltammetry. The respective silica material shows five reduction events (Co3O4 to CoO, CoO to Co), while no redox potentials occurred for the Co3O4 NPs embedded in the carbon matrix.

Mixed copper and titanium hydride powder was hot-pressed and characterized by Carrier Gas Hot Extraction, X-Ray Diffraction, Thermal Gravimetric Analysis coupled with Mass Spectrometry, and Scanning Electron Microscopy. The hot-pressed and five conventional samples were applied for calibration of hydrogen in Glow Discharge Optical Emission and Mass Spectrometry. Up to the introduction of 15 ng/s hydrogen the emission yield model is useful in Glow Discharge Optical Emission Spectrometry. A correlation between saturation and even reversal of the emission yield of the spectral lines H121, H486 and H656 and low sputtering rates was found. Hydrogen effects exist for the spectral lines of Cu(II) 219 and Ti(I) 399. In Glow Discharge Mass Spectrometry, a linear dependency of the 1H ion current on the sputtered mass per time exists over the total range of hydrogen content investigated. Hydrogen effects also exist for the sensitivity of 48Ti and 63Cu. The sputtering rate of two-phase materials depends linearly on the sputtered mass per time of one phase, which allows the sputtering rate of two-phase materials with known composition to be predicted.

We report on the successful application of porous hollow carbon nanospheres consisting of graphitic shells with a hierarchical porosity that were obtained by carbonizing an iron-containing commercially available metal-organic framework, as active material for supercapacitors. The influence of basic key parameters, such as the degree of graphitization and the accessible surface area of the carbons obtained at different temperatures, on the electrochemical performance is discussed in-depth. A high specific capacitance of 91 F g −1 in an aqueous electrolyte and 156 F g −1 using an ionic liquid is achieved. Furthermore a very steady specific capacitance over the course of 10,000 charge-discharge cycles is demonstrated. In addition, electrochemical impedance spectroscopy studies revealed that these carbons can feature a stable performance over several orders of magnitude of frequency, which render them interesting candidates for future electrochemical energy storage systems.

Electrode material characteristics need to be improved urgently to fulfill the requirements for high performance lithium ion batteries. Herein, we report the use of the two-phase alloy Ti80Co20 for...

We report on the synthesis of new metal–organic framework derived carbons using a two-step process employing for the first time a commercially available iron-containing metal–organic framework. The resulting carbons consist mainly of highly graphitic shells due to the highly dispersed iron in the precursor structure which catalyzes the formation of graphitic carbon. In addition, a distinct onion-like morphology is observed, with high total pore volumes of up to 1 cc/g and a hierarchically structured porosity in which the hollow cores of the carbon onions are accessible via smaller micro- and mesopores. As a proof of concept we furthermore demonstrate the inherent structure of this carbon being advantageous for the application in lithium–sulfur batteries as a both confining and contacting host for the active material, yielding capacities of up to 550 mAh/g after 40 cycles.

Thermodynamic data for gaseous SiF2 and SiCl2 known from literature show that these binary subhalides are formed nearly quantitatively at 1376 °C and 1076 °C, respectively, as products of the reaction of elemental silicon with SiF4 or SiCl4 at 110 -2 mbar. Ap- plying the co-condensation technique SiF2 as well as SiCl2 can be trapped at -196 °C and prepared in synthetic scale. Herein, first analy- sis of metastable SiF2 and SiCl2 solutions are presented, showing that

The influence of elemental additives 1–10 at.% Co or 5 at.% Pd on the phase formation of the orthorhombic LaMg 2 Ni phase and its hydrogen reactivity in La 25 Mg 50 Ni 25 alloys was studied. The induction melting, the melt-spinning and the intensive ball milling routes, respectively, were used. By controlled heat treatment of glassy melt-spun Co- or Pd-substituted La 25 Mg 50 Ni 25 ribbons the formation of a La 1− x Mg 2 Ni 1− y Co x + y ( x + y = 0.2) phase in combination with LaMg 3 proceeds or LaMg 2 Ni 0.8 Pd 0.2 as single phase, respectively. Co is dissolved in the LaMg 2 Ni alloy up to 5 at.% and occupies the La positions in the unit cell predominantly. Pd occupies the Ni position in LaMg 2 Ni only. The activation energies for crystallisation E AC of La 1− x Mg 2 Ni 1− y Co x + y and LaMg 2 Ni 0.8 Pd 0.2 were estimated. The most effective method for achieving the substituted hydride LaMg 2 NiH 7 as single phase was the intensive ball milling in a planetary RETSCH mill under a 0.5 MPa hydrogen atmosphere. The elemental substitution of La 25 Mg 50 Ni 25 by 5 at.% Co or 5 at.% Pd reduced the reaction time for the hydride formation drastically from 7.5 h to 3 h for Pd and to 1.5 h for Co. The hydrogen desorption from these substituted hydride powders proceeds in two steps: the decomposition into LaH 2−3 and a solid solution of Co or Pd with Mg 2 Ni with E AT ≈ (75 ± 5) kJ/mol and E AT ≈ (160 ± 5) kJ/mol. The activation energy for decomposition is much higher in both cases as for the pure LaMg 2 NiH 7 . Particularly, the Pd-containing hydride shows reversible interstitial hydrogen absorption/desorption behaviour in the lower temperature region before decomposition and could be of interest for further studies regarding electrochemical applications. The recombination to the starting phases >540 °C or 530 °C, respectively, is combined with the simultaneous evaporation of Mg in both cases of substitution.

To experimentally reveal the correlation between electrodeposited structure and electrolyte convection induced inside the concentration boundary layer, a highly inhomogeneous magnetic field, generated by a magnetized Fe-wire, has been applied to an electrochemical system. The influence of Lorentz and magnetic field gradient force to the local transport phenomena of copper ions has been studied using a novel two-component laser Doppler velocity profile sensor. With this sensor, the electrolyte convection within 500 μm of a horizontally aligned cathode is presented. The electrode-normal two-component velocity profiles below the electrodeposited structure show that electrolyte convection is induced and directed toward the rim of the Fe-wire. The measured deposited structure directly correlates to the observed boundary layer flow. As the local concentration of Cu(2+) ions is enhanced due to the induced convection, maximum deposit thicknesses can be found at the rim of the Fe-wire. Furthermore, a complex boundary layer flow structure was determined, indicating that electrolyte convection of second order is induced. Moreover, the Lorentz force-driven convection rapidly vanishes, while the electrolyte convection induced by the magnetic field gradient force is preserved much longer. The progress for research is the first direct experimental proof of the electrolyte convection inside the concentration boundary layer that correlates to the deposited structure and reveals that the magnetic field gradient force is responsible for the observed structuring effect.

Conventional alkaline solutions used for capacitive performance of electrodeposited cobalt hydroxides have a number of disadvantages as they are corrosive, environmentally unfriendly and provide a small working potential range. In this study, the capacitive properties of electrodeposited cobalt hydroxide/oxide were investigated in 1 M Na 2 SO 4 solution with pH 5.5 by means of cyclic voltammetry, galvanostatic charging/discharging experiments and electrochemical impedance spectroscopy. The capacitance of the cobalt hydroxide/oxide was demonstrated to have high values of 141 F g −1 at scan rate 8 mV s −1 in this 1 M Na 2 SO 4 solution. The anodic potential range is extended by 0.8–1.3 V vs. Ag/AgCl. A good cyclic stability and reversibility were observed.

Using the example of a Zr–Ti–Al–Cu–Ni bulk metallic glass with an ex situ approach, two aspects were studied: (i) the effects of pre-formed corrosion pits on the room temperature deformation behaviour, and (ii) the effect of mechanically generated defects on the local corrosion susceptibility. For the latter, Vickers micro-indents generated with different loads were also employed as model defects. It is revealed that pre-formed corrosion pits act as favourable surface sites to which shear bands are linked and most likely nucleate, which leads to a slight reduction in the maximum compression stress. Further, mechanically generated defects have to be considered as critical weak points at a glassy sample surface which can act as preferential sites for local corrosion initiation and propagation. Local chemical and structural changes due to the formation of shear bands as a response to mechanical load are discussed as possible reasons for this. For potential high-load applications of bulk metallic glasses this interaction must be considered as an important lifetime limiting aspect.

The high heat flux ion beam test facility MARION (Material Research ION Beam test Stand) has been used for ion source conditioning and material testing within the IEK-4 for several years. Mainly small samples have been tested in the past by perpendicular irradiation. In these experiments only 25% of the available power density of MARION (>80 MW/m 2 ) was used so far. The activation of these resources for material testing was realized in the first test phase of the new tungsten divertor element for the JET tokamak. The enhancement of MARION by a new protection scraper is shown. During the last experiments the need of a more flexible handling of the sample itself and of the facility became clear. Based on those experiences an upgrade concept was developed to prepare MARION for future demands allowing the handling of much bigger prototypes. Additionally main emphasis is given to the access to improved (surface) diagnostics for all orientations of the target.

In the frame of the ITER-like Wall (ILW) for the JET tokamak, a divertor row made of bulk tungsten material has been developed for the position where the outer strike point is located in most of the foreseen plasma configurations. In the absence of active cooling, this represents a formidable challenge when one considers the temperature reached by tungsten (TW,surf > 2000 °C) and the vertical gradient ∂T/∂z = 5 × 104 K/m. As the development is drawing to an end and most components are in production, actual 1:1 prototypes are exposed to an ion beam with a power density around 7 MW/m2 on the plasma-facing surface. Advantage is taken of the flexibility of the Marion facility to bombard the tungsten stack under shallow angles of incidence (∼6°) with a powerful beam of ions and neutrals (>70 MW/m2 on axis). The shallow angles are important, with respect to the toroidal wetted surface, for properly simulating the expected performance under actual tokamak conditions. The M arion tests have been used to validate for a few typical cases the thermal calculations that were steadily developed along with the tungsten tile and, at the same time, to gather information on the actual temperatures of individual components. The latter is an important factor to a finer estimation of the power handling capabilities.

The corrosion behaviour of uncoated NdFeB permanent magnets in the non-magnetized and magnetized state was comparatively investigated in H2SO4 solutions by potentiodynamic and potentiostatic polarization experiments. Depth profiles of the corroded surfaces were recorded and an effect of magnetization on the localization of the corrosion attack was identified. The anodic behaviour is discussed on the basis of previously reported results on the corrosion of neodymium and iron and on basis of the magnetic forces acting on the electrochemical system.

Electrodeposition of Bi in magnetic gradient fields was performed from two different electrolytes. The first electrolyte contained only diamagnetic Bi3+-ions; the second one additionally contained electrochemically inert paramagnetic Mn2+-ions. While homogeneous Bi deposits were obtained from the former, structured Bi layers were derived from the latter. The structured deposits show an inverse correlation between deposit thickness and superimposed magnetic field gradient. Minima of film thickness are observed in regions of maximum magnetic gradients. This demonstration of magneto-electrochemical structuring by deposition of diamagnetic ions is discussed considering the acting magnetic forces. Several possibilities explaining the structuring mechanism are presented. Keywords: Magneto-electrodeposition, Bismuth, Electrochemical structuring, Magnetic field gradient force, Heterogeneous magnetic field

The effect of a uniform magnetic field on the hydrogen evolution reaction (HER) during water electrolysis in 0.1 M Na 2 SO 4 solution was investigated. Irrespective of the magnetic field orientation with respect to the electrode surface, the desorption of hydrogen is enhanced by the presence of the magnetic field. This effect is displayed by a reduction of the mean bubble size as well as a narrower bubble size distribution in a magnetic field. Moreover, it is shown that in the presence of an external magnetic field the fractional bubble coverage is strongly retarded. As a consequence the current density is increased since more active sites are available for the reduction processes. These effects are discussed with respect to the Lorentz force driven convection induced by a magnetic field. In order to resolve further the influence of a magnetic field applied in the perpendicular-to-electrode configuration, where the bulk Lorentz force is negligible, a numerical study has been performed. This revealed the mechanism of the improved desorption of a hydrogen bubble from the electrode surface. The numerical study has been validated by a model experiment. Most importantly, it is clearly demonstrated that a magnetic field superposed during water decomposition is a very effective method to intensify hydrogen evolution processes, and it should be possible to significantly improve the energetic efficiency of the hydrogen production via water electrolysis in a magnetic field.

Emotional stress is associated with e.g. increased hormone release, high blood-sugar level and blood pressure. Stress clearly affects metabolism. Whether chronic stress exposure leads to altered urinary compositions with increased risk of CaOx; urolithiasis was examined by investigating the relation between stress burden and urine composition. 29 controls (CG), 29 CaOx stone formers (SF), and 28 patients with chronic inflammatory bowel diseases (CIBD) were advised to avoid unfavorable aliment. Any urolithiasis-related medications were stopped. At day 5, a 24-h urine was collected and comprehensive urinalysis performed. AP (CaOx) index was calculated. Subjects completed a questionnaire designed to measure perceived stress ("Trier-Inventory-of-Chronic-Stress"). Mean AP (CaOx) in CG, SF and CIBD amount to 0.8 (+/-0.3), 1.2 (+/-0.7), and 1.9 (+/-1.2), respectively. Increased AP (CaOx) in SF is mainly attributed to an increased effect of calcium and oxalate, whereas in CIBD this is additionally caused by a reduced effect of citrate, magnesium and volume. Stress dimensions are correlated to any investigated urinary parameter with an absolute value of ror = 0.600; some correlations are statistically significant: whereas in SF only one combination, "lack of social recognition" versus calcium, shows significance, in CIBD various combinations are significantly related. In particular, sodium excretion increases with stress. In CG, some stress dimensions are directly related to citrate; with increasing stress, protection against CaOx crystallization tends to increase. It could be shown that stress load and urinary composition are related by statistical means. The observed metabolic stress response patterns in urinary compositions are different for the distinct groups, thereby, reflecting a conclusive picture. This is in particular in CIBD, for which a link between stress and inflammatory activity and between inflammatory activity and altered urinary composition is well established.

The anodic polarisation behaviour of neodymium was investigated in various solutions (pH 1–12). While in sulphuric acid solution high dissolution rates were observed, spontaneous passivity occurred in phosphoric acid solutions, oxalic acid solutions and sodium hydroxide solutions. However, the stability of these protecting layers strongly depends on the kind and concentration of anions present, especially in acidic environments. A mechanism of the passive layer breakdown is proposed. During pitting corrosion erosive degradation of the electrode was observed. In all solutions, abnormal hydrogen evolution was observed when neodymium was in the active state during anodic polarisation.

Paramagnetic Cu2+-ions have been electrodeposited under application of magnetic field gradients. Obtained deposits show a direct correlation of the distribution of magnetic flux density B at the electrode and the deposit thickness and morphology. In contrast to that no influence on the deposit structure has been observed for deposition of Bi from electrolytes containing diamagnetic Bi3+-ions. This indicates that the structuring effect is mainly based on the action of the magnetic gradient force. A structuring-mechanism has been proposed that also discusses influences of the Lorentz force. Keywords: Magnetoelectrodeposition, Magnetic field gradient, Deposit structuring, Field gradient force, Lorentz force

The formation of the nanostructured orthorhombic LaMg 2 Ni phase using the melt-spinning and the intensive ball milling routes has been studied for the La 25 Mg 50 Ni 25 and La 20 Mg 50 Ni 30 compositions. By controlled heat treatment of glassy melt-spun ribbons the formation of the LaMg 2 Ni phase proceeds at T A ≥ 220 °C ( T A = annealing temperature) for La 25 Mg 50 Ni 25 via the initial formation of LaMg 3 , but occurs for La 20 Mg 50 Ni 30 already at T A ≥ 200 °C in a single reaction. Crystallite sizes of LaMg 2 Ni of ≈30 nm were achieved. The formation enthalpies of LaMg 2 Ni were estimated to Δ H = −320.8 kJ/mol for La 25 Mg 50 Ni 25 and Δ H = −230.0 kJ/mol for La 20 Mg 50 Ni 30 . Intensive ball milling of inductively molten master alloys using a planetary RETSCH mill for 30 h resulted in a crystallite size reduction, e.g. up to 15 nm for LaMg 2 Ni. The formation of the complex hydride LaMg 2 NiH 7 was studied for both alloy compositions by annealing rapidly quenched and crystallised as well as intensively ball milled powder under hydrogen. However, the most effective method for achieving the complex hydride as single phase was found to be intensive ball milling in a planetary RETSCH mill under a 0.5 MPa hydrogen atmosphere. The hydride formation reaction was completed within 3 h for La 20 Mg 50 Ni 30 and within 7.5 h for La 25 Mg 50 Ni 25 . The hydrogen desorption from intensively milled LaMg 2 NiH 7 powder proceeds in two steps. At first, the LaMg 2 NiH 7 decomposes into LaH 2–3 and Mg 2 NiH 0.2–0.3 at T A > 450 °C with a decomposition enthalpy of Δ H ≈ 48 kJ/mol and the recombination of LaMg 2 Ni starts at T A > 540 °C. Above 625 °C the LaMg 2 Ni decomposes by the sublimation of Mg.

Amorphous materials of Zr–Cu–Ni–Al systems have shown attractive electrochemical hydrogen absorption properties. A comparison between Zr 60 Cu 15 Al 10 Ni 10 Pd 5 and Zr 65 Cu 17.5 Al 7.5 Ni 10 reveals that the palladium (Pd) increases the hydrogen absorption capacity. Charging melt-spun Zr 60 Cu 15 Al 10 Ni 10 Pd 5 ribbons electrochemically to different hydrogen-to-metal (H/M) ratios and following the effusion of hydrogen by thermal desorption analysis (TDA) reveals hydrogen desorption from interstitial sites of high energy levels at temperatures below 630 K. Zirconium hydrides are formed above 630 K. At higher temperatures partial desorption of hydrogen occurs. The thermal stability observed with differential scanning calorimetry (DSC) of the amorphous phase has been significantly deteriorated by hydrogen absorption. After hydrogenation, the crystallization behaviour shows suppression of the characteristic quasicrystalline phase and depends on the hydrogen content. Therefore, at low hydrogen concentrations H/M = 0.3, Cu and/or Cu-rich phases are primarily formed while at high hydrogen concentrations H/M ≥ 0.9 Zr-hydride phase(s) are mainly formed.

The effect of a magnetic field in the perpendicular-to-electrode configuration on the hydrogen evolution reaction (HER) was investigated during the deposition of Co. An enhanced desorption of hydrogen in the form of numerous small bubbles was found by combining potentiostatic investigations, coupled with an electrochemical quartz crystal microbalance (EQCM), and simultaneous microscopic observations of the electrode surface. The results are consistent with the recently proposed qualitative model [J.A. Koza, M. Uhlemann, A. Gebert, L. Schultz, Electrochem. Commun. 10 (2008) 1330]. Keywords: Magnetoelectrodeposition, Lorentz force, Micro-MHD, Shadowgraph technique, Desorption of hydrogen

The effect of a uniform magnetic field in perpendicular-to-electrode configuration, on the hydrogen evolution reaction was investigated during the deposition of Fe and CoFe alloys. It was found that the desorption of hydrogen is supported in a magnetic field. This effect is discussed in details with respect to the micro-magnetohydrodynamic convection, which arises due to the fluctuation of the current distribution close to the H2 bubble. Keywords: Magnetoelectrodeposition, Lorentz force, Micro-MHD, Hydrogen evolution reaction, Desorption of hydrogen

The effect of a uniform magnetic field with a flux density up to 1 T and different configurations relative to the electrode surface, on the electrodeposition of Co, Fe and CoFe alloys from acidic sulphate electrolytes has been investigated. It was found that a magnetic field applied parallel to the electrode surface increases the limiting current density and deposition rate due to the magnetohydrodynamic (MHD)-effect caused by the Lorentz force. No significant changes of the limiting current density and deposition rate with a magnetic field applied in the perpendicular to electrode configuration were observed. But in this configuration desorption of hydrogen was found to be supported by a magnetic field. The chemical composition of the deposited alloys was found to be unaffected by the magnetic field. The deposition of CoFe at the highest applied potential (−1600 mV MSE ) was found to be anomalous. At this potential the increase of the interface pH value is sufficient for hydroxyl species formation.

The microstructure of electroplated Cu thin films and the contamination with incorporated additives were investigated in dependence on the galvanostatic deposition parameters and thermal treatment. Sulfur, chlorine, and carbon were analysed as impurities by TEM, AES and SIMS. SIMS measurements revealed that at room temperature S and Cl show a local stability at their incorporation sites, whereas C is capable to segregate out of the Cu layer. Thermally treated Cu layers indicate a segregation of S and a local stability for incorporated Cl. The incorporation of impurities during Cu deposition is linked with a surface coverage of additives. With increasing time for additive adsorption on the sample surface an increased incorporation of impurities into the growing film occurs. Hence, every start of deposition leads to a significantly high incorporation of S, Cl, and C. The application of aged electrolytes generates very impure Cu layers with an increased film roughness. As a result, the recrystallization of the deposited Cu film is slowed down due to the Zehner pinning effect. The final metallization appears more fine-grained and exhibits worse electrical properties.

We present results of a laboratory study of novel electrical resistivity tomography (ERT) sensor materials, whose performance has been assessed in terms of suitability for long-term geoelectrical monitoring. The study has addressed concerns over the longevity of buried ERT sensors required to support nuclear decommissioning at the Sellafield Site in the UK. Electrodes made from three candidate materials and installed in a bentonite grout were subjected to accelerated measurements and electrochemical analyses were carried out on both pristine and used electrodes after extraction from the laboratory tanks. Electrical contact resistance showed significantly different behaviour for stainless steels compared with platinised titanium. Pt-Ti sensors displayed outstanding properties and their stability under operational conditions was remarkable. Their susceptibility to ERT noise, which was expected to be worse due to their higher nobility, was only marginally greater than that of stainless steels. No tangible advantage in terms of electrical performance was found for using higher-grade varieties of stainless steel over a conventional 316L-based design. Crucially, both steel types were affected by the growth of carbonate scales when buried in bentonite. This fundamental process may well be (at least partially) responsible for the frequently encountered increase in contact resistance of stainless-steel electrodes over time.

Cobalt (Co) layers with a thickness of up to 50 nm have been electrodeposited under the influence of magnetic fields up to 10 T aligned perpendicular or parallel to the electrode surface. The crystallographic orientation and the phase composition of these layers have been investigated by X-ray diffraction and transmission electron microscopy. The layers consist mainly of the face centered cubic phase with a 〈111〉 orientation perpendicular to the electrode surface which results from the low surface free energy of these planes. An influence of magnetic fields on the crystallographic orientation has not been observed. It was found that magnetic fields affect the phase composition which results predominantly from the influence of the magnetic fields on the electrochemistry. The nucleation has been studied by in-situ scanning tunneling microscopy.

Amorphous-nanocrystalline Mg50Ni30Y20 and Mg63Ni30Y7 and amorphous Mg65Cu25Y10 alloys were produced by melt-spinning and characterized regarding their microstructure and thermal behaviour using XRD, TEM and DSC. Their electrochemical behaviour in the as-quenched state and after hydrogen charging at −25 mA/cm2 for up to 20 h was studied in electrolytes with pH 5–7 and 13, but mainly in a battery electrolyte: 6 M KOH with pH 14.8 by means of anodic and cathodic polarization measurements. In the as-quenched state, the highest alloys stability was observed at pH 13. At pH 14.8, gradual oxidation and dissolution of copper or nickel governs the anodic behaviour before a passive state is attained. The dissolution of nickel is much more inhibited than that of copper due to its lower tendency to form soluble oxidized ions and to a stabilizing effect of higher fractions of yttrium in the alloy on the passivation. By galvanostatic charging, the Mg65Cu25Y10 alloy shows the highest hydrogen absorption capacity followed by Mg50Ni30Y20 and Mg63Ni30Y7. During the charging process, the alloys exhibit a change in the surface state chemistry, i.e. an enrichment of nickel- or copper-rich species, causing preferential oxidation and dissolution during subsequent exposure under free corrosion and anodic conditions. Mg–Ni–Y alloys demonstrate a higher stability during this treatment in extreme alkaline medium. The reasons for this and consequences regarding the use as electrode materials are discussed in detail.

The thiolate complexes Zn(15]aneN(4))(S-CH2-C6H5)]ClO4 (1) (15aneN(4) = 1,4,8,12-tetraazacyclopentadecane) and Zn(i-14]aneN(4))(S-CH2-C6H5)ICIO4 (2) (i-14aneN(4) = 1, 4,7, 11 -tetraazacyclotetradecane) have been reacted with carbon disulfide. The trithiocarbonate complexes Zn(15]aneN(4))S-C(S)-S-CH2-C6H5]CIO4 1a, monoclinic, space group P2(1)/n, Z = 8, a = 13,2338(1) angstrom, b = 12.9251(2) angstrom, c = 30.1669(4) angstrom, beta = 101.463(1)degrees, V = 5057.1(1) angstrom(3) and Zn(i14]aneN(4))S-C(S)-S-CH2-C6H5]CIO4 2a, orthorhombic, space group P2(1)2(1)2(1), Z = 8, a = 9.9936(1) angstrom, b 22.1261(4) angstrom, c = 22.3192(4) angstrom, V = 4935.2(l) angstrom(3) were obtained. The reaction of 1 with CS2 is second order with a rate constant of k = (57.6 +/- 2.4) x 10(-3) m(-1.)s(-1) at 25 degrees C. The experimentally determined Eyring activation barrier is Delta H-exp(double dagger) = 65.3 +/- 0.7 kJ(.)mol(-1) (Delta S-exp(double dagger) = -49.9 +/- 2.5 J(.)mol(-1.)K(-1)) and a free energy of activation of Delta G* = 80.2 +/- 1.5 kJ(.)mol(-1) at 25 degrees C. To discriminate between an associative and a dissociative mechanism the barriers for both processes were calculated using density functional theory at the C-PCM(B98/G3MP2Large)//B3LYP/ 6-311+G(d) level. The associative mechanism is clearly favored with a difference in free energies of activation of delta Delta G(double dagger) approximate to 80kJ(.)mol(-1). Its calculated barrier Delta G(theor)(double dagger) = 114.3 kJ(.)mol(-1) is in reasonable agreement with the experimental value. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006).

A high-pressure cell for Raman spectroscopical applications has been developed. By using this cell, it is possible to investigate reactions between solids and gases, applying pressures up to 3000 bar. The cell has been successfully tested on the reaction between ferrocene and carbon monoxide. The results point towards a multi-step reaction mechanism. Furthermore, first results are presented for the investigation of the reaction path of CO2 with a zinc thiolate complex. Copyright © 2006 John Wiley & Sons, Ltd.

The thermal behaviour of the rapidly quenched and electrochemically hydrogen-charged Mg 77 Ni 18 Y 5 alloy was studied by means of in situ high temperature X-ray methods. Under high vacuum conditions and in hydrogen atmosphere up to 0.5 MPa without pre-charged hydrogen, the crystalline phase formation is observed at 130 T A 2− x Ni 1− y Y x + y phase and the metastable Mg 6 Ni phase are formed. Pure Mg is detected at T A = 200 °C. Mg 6 Ni decomposes at T A > 250 °C into Mg 2 Ni and Mg and Mg 2− x Ni 1− y Y x + y into Mg 2 Ni and YNi. A gas–solid reaction with hydrogen in the X-ray chamber could not be observed. Samples electrochemically hydrogen-charged with 0.3 6 Ni is inhibited by an increasing hydrogen concentration [H] in the ribbons. Yttrium phases are observed only at T A > 250 °C. The grain sizes of the thermally formed phases decrease with increasing hydrogen content in the as-quenched samples caused by the hydrogen in the grain boundary regions around the Mg 2− x Ni 1− y Y x + y particles. The galvanostatic pre-charging with [H] = 1.42 wt% leads at 250 °C under a hydrogen atmosphere of 0.5 MPa to the formation of the fcc complex Mg 2 NiH 4 besides Mg 2 NiH 0.2−0.3 , YH 2 , YH 3 and MgH 2 . Under desorption conditions (60 kPa hydrogen), the decomposition of the Mg 2 NiH 4 phase to Mg 2 Ni and hydrogen at T A > 250 °C is detected. The sorption process is reversible.

The relation between magnetic fields (B) of different strength and orientation superimposed during electrodeposition and the morphology of Co deposits has been investigated. Experiments concerning morphology, grain size and surface roughness were performed by AFM, SEM and TEM. A superimposed B has already an effect on the morphology and roughness of very thin layers. The roughness of Co layers is influenced by magnetic fields as well as by deposition potential. Holes in the cobalt deposits caused by hydrogen bubble formation during the electrodeposition are avoided, when a magnetic field is applied.

The change of the pH value, the hydrogen evolution reaction, and their effect on the electrodeposition of Co were investigated directly at the surface of a gold mesh with and without superimposition of a magnetic field of 1 T by cyclic voltammetry and chronoamperometry in 0.1 M Na 2 SO 4 with and without addition of 0.01 CoSO 4 . The reduction of hydrogen ions is increased by superimposition of a magnetic field oriented parallel to the electrode surface. The increase of the pH value directly at the surface is lower in an applied magnetic field compared to the case without a magnetic field. This is likely to be due to the enhanced convection generated by the Lorentz force. The discharged hydrogen ions are rapidly compensated. The effect of a magnetic field on the limited current density as well as on the change of pH value is more significant at lower initial pH value. For initial pH values of 3 and 3.5 the deposition of Co under a superimposed magnetic field is improved and the increase of the pH value is low in front of the electrode. This leads to a suppression of the spontaneous formation of hydroxides.

Hydrogen uptake can enhance the neutron embrittlement of reactor pressure vessel (RPV) steels. This suggests that irradiation defects act as hydrogen traps. The evidence of hydrogen trapping was investigated using the small-angle neutron scattering (SANS) method on four RPV steels. The samples were examined in the unirradiated and irradiated states and both in the as-received condition and after hydrogen charging. Despite the low bulk content of hydrogen achieved after charging with low current densities, an enrichment of hydrogen in small microstructural defects could be identified. Preferential traps were microstructural defects in the size range of ≈ > 10 nm in the unirradiated and irradiated samples. However, the results do not show any evidence for hydrogen trapping in irradiation defects.

The efficiency of the syngas-free rhodium catalyzed hydroformylation of olefins with formaldehyde can be significantly improved by the addition of hydrogen gas or formic acid.

It is well known that the addition of nitrogen to steels and stainless steels enhances the passivity and localized corrosion resistance, in addition to improving the mechanical properties. Selective alloying of surfaces of steels and stainless steels with nitrogen could also enhance the corrosion resistance and improve the mechanical properties without affecting the bulk properties. Techniques like ion implantation, laser alloying, nitriding, etc. can be effectively used to introduce very high levels of nitrogen. In addition, these techniques can also produce modified surfaces with novel microstructures to further improve the properties. The surface alloying methods also provide an opportunity to selectively nitrogenate the surface of finished components in order to obtain better properties. The review highlights the techniques, modifications and the properties obtained further.

Thin ribbons of the metallic glass Mg65Cu25Y10, obtained by spinning, were saturated with atomic hydrogen from electrochemical decomposition of water. The maximum amount of absorbed hydrogen was 4 mass %. The hydrogen content was determined by hot extraction. We studied the microstructure of samples with different hydrogen contents by x-ray phase analysis (from the change in the diffuse maximum), atomic force microscopy, scanning electron microscopy, and transmission electron microscopy. When the hydrogen content increases up to 3.6 mass %, the amorphous structure of the Mg65Cu25Y10 alloy is converted to a nanocrystalline structure, with formation of magnesium and yttrium hydrides at room temperature.

The effect of a magnetic field on the electrodeposition of Co has been investigated with respect to the strength and the orientation of the magnetic field (B). Two different effects of the magnetic field B on the electrodeposition of cobalt have been observed. The first is the magnetohydrodynamic (MHD) effect caused by the Lorentz force ( F → L ). The second is an effect due to the paramagnetic force ( F → p ), caused by the concentration gradient ( ∇ → c ) and therefore the gradient of the molar susceptibility ( ∇ → χ m ). The limiting current density and the deposition rate of Co increases if the B-field is oriented parallel to the electrode surface. This is mainly due to the expected convection induced by F → L . Both, the Co deposition and the reduction of hydrogen ions, are affected by this. At high cathodic potentials the contribution of the hydrogen reduction to the process changed, which led to homogeneous deposits. A decreasing deposition rate was measured for B-fields oriented parallel or antiparallel to the flow of ions. These results are attributed to the effect of F → p on the electrochemical processes close to the surface.

Whereas oxidation of 1,2,4-trithiolane (1) with 1 molar equiv. of m-chloroperbenzoic acid (mCPBA) yielded 1,2,4-trithiolane 4-oxide (3) and a small amount of 1,2,4-trithiolane 1-oxide (2), the reaction with 2.5 molar equiv. of mCPBA afforded exclusively 1,2,4-trithiolane 1,4-dioxide (trans-7). The oxidation of 3,3,5,5-tetramethyl-1,2,4-trithiolane (4) with peroxyacetic acid (1 molar equiv. H2O2/AcOH) gave a mixture of regioisomeric 3,3,5,5-tetramethyl-1,2,4-trithiolane 4-oxide (6) as a major product and only traces of 1-oxide 5. Using 2.5 molar equiv. of peroxyacetic acid in reaction with 4 a mixture of both stereoisomers of 3,3,5,5-tetramethyl-1,2,4-trithiolane 1,4-dioxides cis-8 and trans-8 was isolated. Furthermore, 4 was oxidized to 3,3,5,5-tetramethyl-1,2,4-trithiolane 1,1,4,4-tetraoxide (9) using 6 molar equiv. of peroxyacetic acid. The molecular structures of 3, trans-7, trans-8 and 9 were unambiguously established by X-ray structure analysis. Compounds 1–4, trans-7, trans-8 and 9 were investigated by Raman spectroscopy. Ab initio calculations were used to obtain the optimized geometries and the vibrational wavenumbers of the title compounds. The vibrational assignment was accomplished by using the calculated harmonic wavenumbers and their Raman intensities. The calculated values of both structural parameters and the vibrational modes fitted in with experimental data. The spectroscopic changes observed in the spectra were correlated with the structural parameters in order to gain information about the influence of the oxidation on the molecule structure. The experimental data indicated, that in comparison with starting 1,2,4-trithiolanes 1 and 4 their oxidized derivatives showed remarkable shortening of the S–S bonds.

Zr–(Ti)–Cu–Al–Ni metallic glasses exhibit a high thermal stability corresponding to a wide undercooled liquid region. Depending on their composition, the formation of metastable intermediate phases, e.g. a quasicrystalline phase is possible. The combination of early and late transition metals makes these alloys very interesting regarding their interaction with hydrogen. Amorphous Zr 55 Cu 30 Al 10 Ni 5 , Zr 65 Cu 17.5 Al 7.5 Ni 10 and Zr 59 Ti 3 Cu 20 Al 10 Ni 8 ribbons were prepared by melt spinning and their microstructure and thermal behaviour was checked by X-ray diffraction, transmission electron microscopy and differential scanning calorimetry. The cathodic reactivity of alloy samples at different microstructural states and after pre-etching in 1 vol.-% HF was investigated in 0.1 M NaOH by applying potentiodynamic polarisation techniques. Galvanostatically hydrogenated samples were characterised by XRD, DSC, TEM and thermal desorption analysis (TDA). For amorphous Zr 59 Ti 3 Cu 20 Al 10 Ni 8 samples an increase in electrochemical surface capacity by two orders of magnitude is observed after pre-etching. Compared to the quasicrystalline and crystalline alloy, the hydrogen reduction takes place at significantly lower overpotentials. Zr-based alloys cathodically absorb hydrogen up to H/M=1.65 while keeping the amorphous structure. Already small amounts of hydrogen cause a significant decrease of the thermal stability and changes in the crystallisation sequence. The hydrogen desorption is a two-stage process: ( T T >623 K) zirconium hydride formation and subsequent transformation under hydrogen effusion. Hydrogen suppresses the oxygen-triggered formation of metastable phases upon heating and supports primary copper segregation. At very high H/M ratios, severe zirconium hydride formation causes the crystallisation of new compounds.

The influence of hydrogen on the mechanical properties of four austenitic CrNiMo and CrMn alloys with nitrogen contents up to 0.57 wt-% were investigated concerning their resistance against hydrogen embrittlement in correlation to nitrogen content, chemical composition, and hydrogen diffusivity and solubility. Tensile tests were carried out at room temperature and at strain rates between 10-4 and 10-6 s-1 with simultaneous hydrogen charging and after precharging to different hydrogen contents. The mechanical properties have been found to be dependent on both strain rate and hydrogen content in the material. Simultaneous hydrogen charging and mechanical testing have accelerated the failure process owing to a faster hydrogen uptake especially at low strain rates. Hydrogen has shown a softening effect in the elastic range of the stress strain curve, which becomes more pronounced with decreasing strain rate. The favoured mechanism of hydrogen damage of alloys with high nitrogen contents seems to be th...

Electrochemical permeation technique and thermal desorption spectroscopy were used to evaluate the hydrogen diffusion, solubility, and trapping behaviour in nitrogen containing austenitic alloys. The hydrogen diffusion of all alloys obeyed Arrhenius relationships in the studied experimental temperature range. The apparent diffusion coefficients were determined and the relevant activation energies were estimated. Nitrogen at higher concentration (>0.38 wt.%) as well as chromium decrease the hydrogen diffusion whereas nickel has opposite effect. The thermal analysis of all alloys except Cr18Mn18N0.57 shows a main single peak at different heating rates indicating no significant hydrogen interaction with microstructural defects. The alloy Cr18Mn18N shows a shoulder in addition to the peak which is attributed to nitrogen–hydrogen interaction. The activation energy estimated from the thermal analysis is nearly equal to the activation energy for diffusion obtained from the Arrhenius plots of the corresponding alloys.

Glassy Zr65Cu17.5Al7.5Ni10 alloy samples with 0.13 and 0.46 at.% oxygen were prepared by single-roller melt-spinning. Subsequently, the ribbons were electrolytically charged to different hydrogen-to-metal ratios 0.035≤H/M≤1.6. The effect of hydrogen on the thermal stability and on the crystallisation behaviour of the alloy samples was studied by means of differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). With increasing hydrogen content, a reduction of the undercooled liquid region and a significant change in the crystallisation process was observed. Hydrogen was found to suppress the oxygen-triggered formation of the metastable quasicrystalline phase, whereas the metastable f.c.c.-phase formation seems to be less affected. Furthermore, hydrogen-induced copper segregation was detected after long-term charging to high H/M ratios at room temperature and already for samples with low hydrogen contents upon heating. At very high H/M ratios, the thermal behaviour of the investigated Zr65Cu17.5Al7.5Ni10 alloy samples is determined by preferential zirconium hydride formation and successive decomposition causing the formation of new stable intermetallic phases with lower zirconium content.

The hydrogenation process of Sm 2 Fe 17− y Ga y ( y =0–2) was studied. X-ray investigations show a decreasing hydrogen solubility in the intermetallic alloy with increasing Ga-content from 4.0±0.3 atoms per formula unit for Sm 2 Fe 17 to 2.85±0.05 for Sm 2 Fe 15 Ga 2 . The larger Ga atoms reduce the size of the interstitial sites and thereby the maximum hydrogen concentration is decreased. The behaviour of the lattice parameters a and c with increasing Ga content points to a changed hydrogen distribution on the interstitial sites, becoming more statistical. In situ observations by means of high temperature X-ray diffraction show that the hydrogen absorption process is diffusion controlled. The hydrogen absorption starts at an annealing temperature of 120–140°C in all cases. The solubility of hydrogen decreases with increasing temperature. The hydrogen is completely desorbed above 350°C in all cases. The absorption/desorption process is reversible between room temperature and 400°C. Annealing at temperatures above 400°C leads to the decomposition of the Sm 2 Fe 17 phase, indicated by emerging of α-Fe. The formation of SmH x is established at 600°C. The decomposition temperature increases with increasing Ga-content. Up to 750°C, only Sm 2 Fe 17 is completely decomposed.

Zr 55 Cu 30 Al 10 Ni 5 metallic glass exhibits high thermal stability, and as it contains early and late transition metal elements (ETM/LTM), it is of interest to study its hydrogenation properties. Charging melt-spun ribbons electrochemically to different hydrogen-to-metal (H/M) ratios and following the effusion of hydrogen by thermal desorption analysis (TDA) reveals hydrogen desorption from high interstitial-site energy levels at temperatures below 623 K. Zirconium hydrides are formed above 623 K. At higher temperatures partial desorption of hydrogen occurs. Simultaneously, transformation to different hydride phases takes place in the order tetragonal e-Zr-hydride, cubic δ-Zr-hydride and a mixture of (α+β)-Zr-hydride. Thermal stability investigations by differential scanning calorimetry (DSC) point out the exothermic peaks of formation/transformation to different Zr-hydride phases. The formation of zirconium hydride causes depletion in the number of free Zr atoms leading, in turn, to different crystalline phases upon crystallisation. X-ray diffraction (XRD) reveals the formation of different crystalline phases for different H/M ratios. For a H/M-ratio of 0.37 a hexagonal AlZr 2 phase forms at 753 K, whereas for high hydrogen contents of 0.7 2 Zr forms already at 713 K. In contrast, the uncharged ribbons crystallise at 771 K by formation of a mixture of metastable fcc NiZr 2 -type phase, orthorhombic NiZr and tetragonal CuZr 2 phases.

A series of oxo-rhenium complexes of the type ReO(LLL)(LLLH) with tridentate diacidic ligands (LLLH2) containing the donor set $$O\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{ } N\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{ } O\left( N \right)$$ has been synthesized and characterized. X-ray analyses were carried out for benzoylacetone-2-hydroxyanilato(2-)-benzoylacetone-2-hydroxyanilato-oxo-rhenium(V) ReO(BAHA)2 1, [2,6-diphenylacylpyridinato(2-)]-2,6-diphenylacylpyridinato-oxo-rhenium(V) ReO(DPAP)2 2, [2-pyrrolaldehyde-2′-hydroxyanilato-(2-)]-2-pyrrolaldehyde-2′-hydroxyanilato-oxo-rhenium(V) ReO(PAHA)2 3, {4-[1-(N′-benzoylhydrazino)-1-phenyl-methyliden]-3-methyl-1-phenyl-pyrazol-5-onato-(2-)} – {4-[1-(N′-benzoylhydrazino)-1-phenyl-methyliden]-3-methyl-1-phenyl-pyrazol-5-onato}-oxo-rhenium(V) ReO(BHMP)2 5, and for the ligand 4-[1-(N′-benzoylhydrazino)-1-phenyl-methyliden]-3-methyl-1-phenyl-pyrazol-5-one (BHMP). In all the oxo-rhenium complexes the rhenium is in a distorted octahedral coordination environment with one ligand acting as tridentate in the equatorial plane and the other ligand acting as bidentate in the axial position. The Re — Nbond lengths were found to be in the range of 2.01 to 2.18 A depending on the nature of the bond caused by mesomeric and steric effects of the ligands. In order to check the bonding relationships, molecular orbital calculations with Gaussian 94 were carried out. Additionally force field calculations were performed using the Extensible Systematic Force Field (ESFF). This was done to examine the ability of the ESFF to represent the bonding relationships in order to provide reasonable input data for MO calculations.

The ligand exchange reactions of ReCl4(PPh3)2, ReOCl3(PPh3)2 and NiCl2(PPh3)2 with acetylacetone thiobenzoylhydrazone have been studied. An unexpected template reaction at the ReO3+ core forming the new tetradentate triacidic ligand triacetylmethane bis(thiobenzoylhydrazone) will be described and discussed. The final products were characterized by elemental analysis, mass spectroscopy, 1H NMR, IR, UV-VIS spectroscopy and X-ray structural analysis. [Acetylacetone thiobenzoylhydrazonato(2-)]chloro-oxorthenium(V) was isolated as an intermediate. The crystal structures have been determined of [triacetylmethane bis(thiobenzoylhydrazonato) (3-)- S,S′,N,N′]oxorhenium(V) C21H19N4O2S2Re, monoclinic P2 1 /m, a = 7.451(1), B = 11.262(3), c = 12.639(4) A , β = 90.66(2)°, Z = 2, R 1 = 0.0445 , and [acetylacetone thiobenzoylhydrazonato(2-)]-triphenylphosphane-nickel(II) C30H27N2OSPNi, orthombic Pbca, a = 16.658(2), b = 14.725(2), c = 21.950(2) A , Z = 8, R 1 = 0.0283 .

The structures of the zinc and cadmium complexes of 4-acyl-3-methyl-1-phenyl-5-pyrazolones, [Zn-(C 18 H 23 N 2 O 2 ) 2 (H 2 O)] and [Cd(C 28 H 43 N 2 O 2 ) 2 (C 2 H 6 O) 2 ], show remarkable differences. In the case of zinc, the coordination number is five and a square-pyramidal structure was found, which is realized by the coordination of one molecule of water in the apical position. The coordination polyhedron is significantly distorted towards a trigonal-bipyramidal arrangement. The cadmium compound contains two coordinated ethanol molecules and is octahedral.