Fabrication of Fe-Co-C thin films using facing targets sputtering method

We report the fabrication of carbon-doped (0-9 at.%) Fe-Co thin films deposited using facing targets sputtering method. Adding carbon of 2.5 at.% has an effect on decreasing coercivity in the case that the internal stress is approximately zero. Further addition of carbon does not influence the soft magnetic properties, whereas the saturation flux density decreases down to 2 T. The lowest coercivity of 12 Oe in hard axis is obtained with the saturation flux density of 2.4 T and clear uniaxial anisotropy (anisotropy field: 200 Oe) in the (Fe₆₅Co₃₅)_97.5C_2.5 film. The Fe-Co-C film exhibits better frequency characteristics than Fe-C films due to higher anisotropy field and saturation flux density.     

A novel bioconversion of L-fructose to L-glucose by Klebsiella pneumoniae

A bacterial strain AS1 belonging to the genus Ochrobactrum, was isolated from an enriched phenol-activated sludge in Egypt. This strain grew aerobically on phenol as the sole carbon source using the meta-cleavage pathway at high phenol-degrading rates compared with those in a previous report.     

A method of direct particle deposition on a carbon planchet to study mineral dust in human lung by scanning electron microscopy

Following Na-hypochlorite digestion of lung tissue, mineral particles extracted in the chloroform layer were deposited directly on a pre-smoothed carbon planchet for combined scanning electron microscopy and X-ray energy dispersive spectrometry (SEM and XEDS). Total mineral particle counts were obtained, and detailed physical characteristics of the fibrous particles were documented at 600, 1,500, 4,500 and 9,000 x in three lungs without, and one lung with, histories of occupational exposure. This preparation method was simple, collected more than 99% of identifiable mineral particles in the chloroform layer, gave excellent object to background contrast without heavy metal coatings, and was suitable for XEDS. Comparable fibrous particles from the chloroform layer could also be studied by selected-area electron diffraction to complement the results of XEDS. By this method, we found particles or fibers larger than 0.1 μm were readily counted and measured at 4,500 x. At 600 x, ferruginous bodies were found to be more than twice in number than when sought for by light microscopy. It was determined that 4,500 x is the most efficient magnification to examine and diagnose this type of specimen. The present study illustrates the importance of determining the most efficient magnification to be utilized in particle counts.     

加热速率对逆转变奥氏体微观组织的影响

 为了研究连续加热过程中加热速率对逆转变奥氏体微观组织的影响,通过热膨胀仪和EBSD研究了不同加热速率下部分逆相变和完全逆相变后的微观组织。结果表明,高加热速率促进了块状奥氏体的形成,而低加热速率有利于针状奥氏体的形成,且加热速率越大,最终逆转变完成时奥氏体晶粒尺寸越微细。高加热速率使得奥氏体形核和长大被推向高温区进行,高温区块状奥氏体为置换性合金元素非配分长大模式,长大速率极快。因此,高加热速率促进了块状奥氏体的形成。     

Microporous coordination polymers of cobalt(II) and manganese(II) 2,6-naphthalenedicarboxylate: preparations, structures and gas sorptive and magnetic properties

Two isostructural coordination polymers M₃(NDC)₃(DMF)₄ (M = Co (1), Mn (2); H₂NDC = 2,6-naphthalenedicarboxylic acid; DMF = N,N′-dimethylformamide) were prepared through conventional and microwave-assisted solvothermal methods. Single crystal X-ray analysis indicated that both complexes crystallized in the monoclinic system with space group C2/c. Powder X-ray diffraction (PXRD) patterns of the bulk samples for the two complexes obtained from microwave-assisted solvothermal syntheses matched well with the simulated ones from the single crystal data as well as the ones prepared by conventional solvothermal method. These microporous cobalt(II) and manganese(II) coordination polymers undergo reversible structural change upon desolvating, giving stable microporous frameworks containing unsaturated metal sites, and resolvating. The desolvated complexes showed different nitrogen gas adsorption capabilities but very close hydrogen adsorption behaviors. Variable-temperature magnetic susceptibilities of 1 and 2 revealed the weak antiferromagnetic coupling between the adjacent metal ions bridged by carboxylate.