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This work describes the experimental characterization of a commercial sodium–nickel chloride battery and the investigation on a state-of-the-art model that represents the battery behavior. This battery technology is considered very promising but it has not fully been exploited yet. Besides improvements on the technological side, accurate models of the battery should be found to allow the realization of Battery Management Systems with advanced functions. This achievement may extend the battery exploitation to its best. The paper describes the experimental set-up and the model parameter identification process, and discusses the identified parameters and the model validation tests. The comparison between model simulations and experiments shows that the model is rather accurate for low-current rates, but it loses accuracy and it is not able to reproduce with fidelity the battery behavior at low states of charge or at high current rates. Further research efforts and refinements of the model are necessary to make available a sodium–nickel chloride battery model accurate in any operating condition.

The reduction by hydrogen and the thermal decomposition of a siliceous nickel laterite ore in the presence of NaCl were studied using thermogravimetric analysis (TGA). Reduction tests on H2 atmosphere in rotary kiln were performed in the presence of NaCl and the product of the reaction was leached in ammoniacal solution. The presence of only 1 pct of NaCl in the furnace increased the nickel extraction values from ≈ 3 to ≈ 90 pct when the experiment was carried out at 850 °C. According to the results of X-ray diffractometry and TGA, the presence of NaCl in the system and the reducing atmosphere of H2 promote the segregation of nickel according to the following steps: (1) Nickel oxide reduction by hydrogen: NiO + H2(g) → Ni + H2O(g). (2) Formation of HCl: Al2SiO5 + 2NaCl + SiO2 + H2O → 2HCl(g) + 2NaAlSiO4. (3) Chlorination of metallic nickel by HCl: Ni + 2HCl(g) → NiCl2 + H2(g). (4) Reduction of nickel chloride by hydrogen: NiCl2 + H2(g) → Ni + 2HCl(g).

The aim of this study was to investigate the role of selenoprotein M (SelM) in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin. At 21 d after intraperitoneal injection of nickel chloride (NiCl 2 ) and/or melatonin into male wild-type (WT) and SelM knockout (KO) C57BL/6J mice, NiCl 2 was found to induce changes in the microstructure and ultrastructure of the hearts of both WT and SelM KO mice, which were caused by oxidative stress, endoplasmic reticulum stress, and apoptosis, as evidenced by decreases in malondialdehyde (MDA) content and total antioxidant capacity (T-AOC) activity. Changes in the messenger RNA (mRNA) and protein expression of genes related to endoplasmic reticulum stress (activating transcription factor 4 (ATF4), inositol-requiring protein 1 (IRE1), c-Jun N-terminal kinase (JNK), and C/EBP homologous protein (CHOP)) and apoptosis (B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), Caspase-3, Caspase-9, and Caspase-12) were also observed. Notably, the observed damage was worse in SelM KO mice. Furthermore, melatonin alleviated the heart injury caused by NiCl 2 in WT mice but could not exert a good protective effect in the heart of SelM KO mice. Overall, the findings suggested that the antioxidant capacity of SelM, as well as its modulation of endoplasmic reticulum stress and apoptosis, plays important roles in nickel-induced heart injury.

Sodium‐metal chloride batteries are considered a sustainable and safe alternative to lithium‐ion batteries for large‐scale stationary electricity storage, but exhibit disadvantages in rate capability. Several studies identify metal‐ion migration through the metal chloride conversion layer on the positive electrode as the rate‐limiting step, limiting charge and discharge rates in sodium‐metal chloride batteries. Here the authors present electrochemical nickel and iron chlorination with planar model electrodes in molten sodium tetrachloroaluminate electrolyte at 300 °C. It is discovered that, instead of metal‐ion migration through the metal chloride conversion layer, it is metal‐ion diffusion in sodium tetrachloroaluminate which limits chlorination of both the nickel and iron electrodes. Upon charge, chlorination of the nickel electrode proceeds via uniform oxidation of nickel and the formation of NiCl2 platelets on the surface of the electrode. In contrast, the oxidation of the iron electrodes proceeds via localized corrosion attacks, resulting in nonuniform iron oxidation and pulverization of the iron electrode. The transition from planar model electrodes to porous high‐capacity electrodes, where sodium‐ion migration along the tortuous path in the porous electrode can become rate limiting, is further discussed. These mechanistic insights are important for the design of competitive next‐generation sodium‐metal chloride batteries with improved rate performance. Electrochemical de‐/chlorination of nickel and iron model electrodes is studied in molten sodium tetrachloroaluminate at 300 °C in a planar cell geometry. While the transport of metal‐ions through the melt emerges as rate‐limiting process in both cases, nickel and iron electrodes exhibit different chlorination behaviors. This results in dissimilar rate capabilities and cycle life.

Battery models are mathematical systems that aim to simulate real battery cell sufficiently accurately. Finding a comprise between complexity, computational effort and accuracy is thereby key. In particular, modelling sodium–nickel–chloride/iron-chloride cells (Na-NiCl2/FeCl2), as a promising alternative for stationary energy storage, bears some challenges. The literature shows a few interesting approaches, but in most of them the second active material (NiCl2 or FeCl2) or the entire discharging/charging cycle is not considered. In this work, an electrochemical and thermal model of Na-NiCl2/FeCl2 battery cells is presented. Based on an equivalent circuit approach combined with electrochemical calculations, the hybrid model provides information on the performance of the cell for charging and discharging with a constant current. By dividing the cathode space into segments, internal material and charge flows are predicted, allowing important insights into the internal cell processes. Besides a low calculation effort, the model also allows a flexible adaption of cathode composition and cell design, which makes it a promising tool for the development of single battery cells as well as battery modules and battery systems.

The size-dependent and shape-dependent characteristics that distinguish nanoscale materials from bulk solids arise from constraining the dimensionality of an inorganic structure 1 – 3 . As a consequence, many studies have focused on rationally shaping these materials to influence and enhance their optical, electronic, magnetic and catalytic properties 4 – 6 . Although a select number of stable clusters can typically be synthesized within the nanoscale regime for a specific composition, isolating clusters of a predetermined size and shape remains a challenge, especially for those derived from two-dimensional materials. Here we realize a multidentate coordination environment in a metal–organic framework to stabilize discrete inorganic clusters within a porous crystalline support. We show confined growth of atomically defined nickel( ii ) bromide, nickel( ii ) chloride, cobalt( ii ) chloride and iron( ii ) chloride sheets through the peripheral coordination of six chelating bipyridine linkers. Notably, confinement within the framework defines the structure and composition of these sheets and facilitates their precise characterization by crystallography. Each metal( ii ) halide sheet represents a fragment excised from a single layer of the bulk solid structure, and structures obtained at different precursor loadings enable observation of successive stages of sheet assembly. Finally, the isolated sheets exhibit magnetic behaviours distinct from those of the bulk metal halides, including the isolation of ferromagnetically coupled large-spin ground states through the elimination of long-range, interlayer magnetic ordering. Overall, these results demonstrate that the pore environment of a metal–organic framework can be designed to afford precise control over the size, structure and spatial arrangement of inorganic clusters. The pore space in the metal–organic framework Zr 6 O 4 (OH) 4 (bpydc) 6 can be used as a scaffold to grow precisely defined atomically thick sheets of metal halide materials, taking advantage of multiple binding sites to direct complexation of the metal ions; these metal halide nanosheets fill the size gap between discrete molecular magnets and bulk magnetic materials, with potentially unusual magnetic properties arising from this size regime.

The results are reported concerning the production of methyl acetate in the halide-free vapor-phase methanol carbonylation (MC) over NiCl 2 –CuCl 2 based catalysts on activated carbons and honeycomb cordierite supports. The formation of the MeOAc with the yield of 18% over nickel-copper chlorides on the BAC-A grade carbon support is shown to be facilitated by the optimal combination of the characteristics of the porous structure (mesopores with an average diameter of ~ 7 nm) and the surface acidity of the catalyst. 15% of MeOAc yield over NiCl 2 –CuCl 2 /cordierite, commensurate with the Y MeOAc for NiCl 2 –CuCl 2 /AC, is achieved due to advantages of structured systems in comparison with the highly porous granular ones, including more efficient mass transfer and heat removal as well as the increased outputs per active components loadings. Using CuO–ZnO–NiO/Al 2 O 3 /cordierite (to generate CO as a carbonylation agent by MeOH decomposition) and NiCl 2 –CuCl 2 /AC(or cordierite) catalysts placed in series-connected flow-type reactors or in a single reactor with two different temperature zones provides producing methyl acetate in a carbon monoxide free gas feedstock with the MeOAc yields of 13–16.5% in “self-carbonylation” tandem process. Graphic Abstract

Alkene hydrocarbonation reactions have been developed to supplement traditional electrophile-nucleophile cross-coupling reactions. The branch-selective hydroalkylation method applied to a broad range of unactivated alkenes remains challenging. Herein, we report a NiH-catalysed proximal-selective hydroalkylation of unactivated alkenes to access β- or γ-branched alkyl carboxylic acids and β-, γ- or δ-branched alkyl amines. A broad range of alkyl iodides and bromides with different functional groups can be installed with excellent regiocontrol and availability for site-selective late-stage functionalization of biorelevant molecules. Under modified reaction conditions with NiCl 2 (PPh 3 ) 2 as the catalyst, migratory hydroalkylation takes place to provide β- (rather than γ-) branched products. The keys to success are the use of aminoquinoline and picolinamide as suitable directing groups and combined experimental and computational studies of ligand effects on the regioselectivity and detailed reaction mechanisms. Difunctionalization of olefins is an ongoing and important focus of synthetic organic chemistry. Here the authors report a nickel-catalysed hydroalkylation of unactivated alkenes to obtain branched alkyl carboxylic acids or alkyl amines, using aminoquinoline and picolinamide as directing groups.

Heavy metals such as cadmium, arsenic and nickel are classified as carcinogens. Although the precise mechanism of carcinogenesis is undefined, heavy metal exposure can contribute to genetic damage by inducing double strand breaks (DSBs) as well as inhibiting critical proteins from different DNA repair pathways. Here we take advantage of two previously published culture assay systems developed to address mechanistic aspects of DNA repair to evaluate the effects of heavy metal exposures on competing DNA repair outcomes. Our results demonstrate that exposure to heavy metals significantly alters how cells repair double strand breaks. The effects observed are both specific to the particular metal and dose dependent. Low doses of NiCl2 favored resolution of DSBs through homologous recombination (HR) and single strand annealing (SSA), which were inhibited by higher NiCl2 doses. In contrast, cells exposed to arsenic trioxide preferentially repaired using the \"error prone\" non-homologous end joining (alt-NHEJ) while inhibiting repair by HR. In addition, we determined that low doses of nickel and cadmium contributed to an increase in mutagenic recombination-mediated by Alu elements, the most numerous family of repetitive elements in humans. Sequence verification confirmed that the majority of the genetic deletions were the result of Alu-mediated non-allelic recombination events that predominantly arose from repair by SSA. All heavy metals showed a shift in the outcomes of alt-NHEJ repair with a significant increase of non-templated sequence insertions at the DSB repair site. Our data suggest that exposure to heavy metals will alter the choice of DNA repair pathway changing the genetic outcome of DSBs repair.

Ni–Mo alloy coatings were deposited on a copper base material from a non-aqueous plating bath based on a deep eutectic solvent (DES) of choline chloride and propylene glycol in a 1:2 molar ratio containing 0.2 mol dm −3 NiCl 2 · 6H 2 O and 0.01 mol dm −3 (NH 4 ) 6 Mo 7 O 24 ·4H 2 O. Uniform and adherent Ni–Mo deposits with a nodular morphology were obtained at all the deposition potentials investigated (from − 0.5 to − 0.9 V vs. Ag). By shifting the potential from − 0.5 to − 0.9 V, the deposition current density increased from − 0.4 to − 1.5 mA cm −2 and the overall surface roughness increased. It was also accompanied by an increase in the Mo content from ~ 7 to ~ 13 wt% in the potential range from − 0.5 to − 0.7 V. A further change in the potential from − 0.8 to − 0.9 V caused a decrease in the Mo content to ~ 10 wt% and a deterioration in the quality of the coating. For the most uniform coating, deposited at − 0.6 V and having a thickness of ca. 660 nm, the crystallite size did not exceed 10 nm. With the content of Ni (89 at.%) and Mo (11 at.%), the selected area electron diffraction (SAED) analysis allowed us to identify the cubic phase Ni 3.64 Mo 0.36 . The corrosion resistance of Ni–Mo coatings in 0.05 mol dm −3 NaCl solution generally increased during exposure of 18 h, as evidenced by ever higher polarization resistance. Finally, regardless of the applied deposition potential, low corrosion currents (in the range of 0.1–0.3 μA cm −2 ) have been measured for the coatings. EIS revealed that charge transfer resistances were the highest (57–67 kΩ cm 2 ) for coatings deposited at − 0.5 V, − 0.6 V and − 0.7 V. Further increase in the deposition potential in the negative direction was unfavorable.