{2,2′-[5-Bromo­pyridine-2,3-diylbis(nitrilo­methyl­idyne)]diphenolato}chlorido(dimethyl­formamide)manganese(III)

In the title complex, [Mn(C19H12BrN3O2)Cl(C3H7NO)], the MnIII ion is coordinated by two N and two O atoms from the tetra­dentate Schiff base ligand, one O atom from the dimethyl­formamide ligand and a Cl anion in a distorted octa­hedral geometry. In the crystal structure, weak inter­molecular C—H⋯Cl hydrogen bonds link the mol­ecules into centrosymmetric dimers with a short distance of 3.878 (3) Å between the centroids of the aromatic rings

Cloud Point Extraction for the Determination of Trace Amounts of Cobalt in Water and Food Samples by Flame Atomic Absorption Spectrometry

A cloud point extraction (CPE) procedure which was developed for the separation and preconcentration of trace amounts of cobalt is combined with �ame atomic absorption spectrometry (FAAS) to determine trace amounts of cobalt in water and food samples. e procedure is based on the formation of the hydrophobic complex between Co(II) and 4-methoxy-2-sulfobenzenediazoaminoazo-benzene (MOSDAA) followed by its extraction into a Triton X-114 surfactant-rich phase. e parameters such as pH of sample, concentrations of MOSDAA and Triton X-114, equilibrium temperature, and equilibrium time, which affect both complexation and extraction, are optimized. Under the selected optimum conditions, the preconcentration of 10.0 mL, 0.1 g mL −1 Co(II) solution results in a limit of detection of 0.47 ng mL −1 (3 ) and an enrichment factor of 19. A relative standard deviation of 2.78% ( , 1 g mL −1 ) for the determination of Co(II) is obtained. e proposed method was applied for the determination of trace amounts of cobalt in river water and millet samples with satisfactory results

Effect of Temperature and Material Flow Gradients on Mechanical Performances of Friction Stir Welded AA6082-T6 Joints

The temperature and material flow gradients along the thick section of the weld seriously affect the welding efficiency of friction stir welding in medium-thick plates. Here, the effects of different gradients obtained by the two pins on the weld formation, microstructure, and mechanical properties were compared. The results indicated that the large-tip pin increases heat input and material flow at the bottom, reducing the gradient along the thickness. The large-tip pin increases the welding speed of defect-free joints from 100 mm/min to 500 mm/min compared to the small-tip pin. The ultimate tensile strength and elongation of the joint reached 247 MPa and 8.7%, equal to 80% and 65% of the base metal, respectively. Therefore, reducing the temperature and material flow gradients along the thickness by designing the pin structure is proved to be the key to improving the welding efficiency for thick plates

Facile Synthesis of Thieno[2,3-<i>d</i>]pyrimidine Derivatives Using Inorganic Base Catalysis

<div><p></p><p>Potassium carbonate as inorganic base catalyst was used to develop an efficient synthetic procedure for the preparation of thieno[2,3-d]pyrimidine derivatives. The molecular structure of the newly synthesized compounds were confirmed by NMR spectral data.</p> </div

Ce‐filled Ni1.5Co2.5Sb12 Skutterudite Thin Films with Record‐High Figure of Merit And Device Performance

Realizing high thermoelectric performance in CoSb3 skutterudite-based thin films and their devices is historically challenging, especially due to the lack of high-performing thin-film-based device working at medium-to-high temperatures. Here, a record-high ZT of 1.1 is achieved at 683 K in an n-type Ce0.3Ni1.5Co2.5Sb12 thin film, fabricated from a self-designed target via advanced pulsed laser deposition. Both experimental and computational results confirm that the Ce-filling and metal-featured nanoinclusions such as CeSb contribute to high electrical conductivity, while the Ni-doping and significantly strengthen the energy filtering effect that occurs at the dense interfaces between the Ce0.3Ni1.5Co2.5Sb12 matrix and the nanoinclusions which leads to a large Seebeck coefficient, giving rise to such a high ZT. In addition, a new-type CoSb3 thin-film-based device is successfully fabricated, which exhibits a high output power density of 8.25 mW cm−2 at a temperature difference of 140 K and a cold-side temperature of 573 K, indicating the potential for application to medium-to-high-temperature power generation scenarios.</p

Fast Fabrication of High‐Performance CoSb3‐Based Thermoelectric Skutterudites via One‐Step Yb‐Promoted Peritectic Solidification

As a most promising mid-temperature thermoelectric material, CoSb3-based bulk material exhibits an applicable figure-of-merit (ZT) of more than one. However, their fabrication is historically time-consuming due to the long-time solid-state phase transitions from CoSb2 to CoSb3. To overcome this challenge, here, a fast one-step process is developed to fabricate n-type Yb-doped CoSb3 with stable ZT of 1.12 at 765 K in 2 and CoSb2 + Liquid → CoSb3, optimizes power factor, and suppresses thermal conductivity. Moreover, the dense grains, induced by the one-step crystallization, result in outstanding mechanical properties with a Young's modulus of 171.4 GPa and a hardness of 8.8 GPa in the Yb-doped CoSb3. This study indicates that the fast one-step fabrication route can effectively promote the practical applications of CoSb3-based thermoelectrics and provide guidance for thermoelectric fabrication via rational phase design.</p

High-performance flexible p-type Ce-filled Fe3CoSb12 skutterudite thin film for medium-to-high-temperature applications

P-type Fe3CoSb12-based skutterudite thin films are successfully fabricated, exhibiting high thermoelectric performance, stability, and flexibility at medium-to-high temperatures, based on preparing custom target materials and employing advanced pulsed laser deposition techniques to address the bonding challenge between the thin films and high-temperature flexible polyimide substrates. Through the optimization of fabrication processing and nominal doping concentration of Ce, the thin films show a power factor of >100 μW m−1 K−2 and a ZT close to 0.6 at 653 K. After >2000 bending cycle tests at a radius of 4 mm, only a 6 % change in resistivity can be observed. Additionally, the assembled p-type Fe3CoSb12-based flexible device exhibits a power density of 135.7 µW cm−2 under a temperature difference of 100 K with the hot side at 623 K. This work fills a gap in the realization of flexible thermoelectric devices in the medium-to-high-temperature range and holds significant practical application value.</div