MoS 2 and Ni-promoted MoS 2 catalysts supported on γ-Al 2 O 3 , siliceous SBA-15, and Zr-and Ti-modified SBA-15 were explored for the simultaneous hydrodesulfurization (HDS) of dibenzothiophene (DBT) and hydrodenitrogenation (HDN) of o-propylaniline (OPA). In all cases, OPA reacted preferentially via initial hydrogenation, and DBT was converted through direct sulfur removal. HDN and HDS activities of MoS 2 catalysts are determined by the dispersion of the sulfide phase. Ni promotion increased its dispersion and activity for DBT HDS and also increased the rate of HDN via enhancing the rate of hydrogenation. On nonpromoted MoS 2 catalysts, HDS was strongly inhibited by NH 3 , and the addition of Ni dramatically reduced this inhibiting effect. The conclusion is that HDS is proportional to the concentration of Mo and Ni on the edges of sulfide particles. In contrast, the direct hydrodenitrogenation of OPA occurs only on accessible Mo cations and, hence, decreases with increasing Ni substitution. The nature of the support influences the dispersion of the nonpromoted catalysts as well as the decoration degree of Ni on the edges of the Ni−Mo−S phase. Furthermore, the acidity of the support influences the acidity of the supported sulfide phase, which may play an important role in HDN.

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Porous Magnesium (Mg) is a promising biodegradable scaffold for treating critical-size bone defects, and as an essential element for human metabolism, Mg has shown sufficient biocompatibility. Its elastic moduli and yield strengths are closer to those of cortical bone than common, inert metallic implants, effectively reducing stress concentrations around host tissue as well as stress shielding. More importantly, Mg can degrade and be absorbed in the human body in a safe and controlled manner, thereby reducing the need for second surgeries to remove implants. The development of porous Mg scaffolds via conventional selective laser melting (SLM) techniques has been limited due to Mg’s low boiling point, high vapor pressures, high reactivity, and non-ideal microstructures in additively manufactured parts. Here we present an exciting alternative to conventional additive techniques: 3D weaving with Mg wires that have controlled chemistries and microstructures. The weaving process offers high throughput manufacturing as well as porous architectures that can be optimized for stiffness and porosity with topology optimization. Once woven, we dip-coat the weaves with polylactic acid (PLA) to enhance their strength and corrosion resistance. Following fabrication, we characterize their mechanical properties, corrosion behavior, and cell compatibility in vitro, and we use an intramuscular implantation model to evaluate their in vivo corrosion behavior and tissue response.