Which cleavage do you prefer? With a combination of density functional theory (DFT) calculations, surface science studies, and reactor evaluations, Mo(2)C is identified as a highly selective HDO catalyst to selectively convert biomass-derived oxygenates to unsaturated hydrocarbons through selective C-O bond scissions without C-C bond cleavage. This provides high-value HDO products for utilization as feedstocks for chemicals and fuels; this also reduces the overall consumption of H2 .

Selectively cleaving the C=O bond outside the furan ring of furfural is crucial for converting this important biomass-derived molecule to value-added fuels such as 2-methylfuran. In this work, a combination of density functional theory (DFT) calculations, surface science studies, and reactor evaluation identified molybdenum carbide (Mo2 C) as a highly selective deoxygenation catalyst for converting furfural to 2-methylfuran. These results indicate the potential application of Mo2 C as an efficient catalyst for the selective deoxygenation of biomass-derived oxygenates including furanics and aromatics.

Controlling the activity and selectivity of hydrodeoxygenation (HDO) of biomassderivatives is critical for the utilization of biomass as renewable sources for chemicals and fuels. Furfural, produced by the hydrolysis and dehydration of xylose from hemicellulose, is a promising biomass-derivative to produce important biofuels like 2-methylfuran. Using a combination of density functional theory (DFT) calculations and surface science measurements on Fe/Ni(111) model surfaces, our results indicate that furfural bonds to the bimetallic surfaces primarily through the C=O bond with the furan ring tilted away from the surface, leading to the production of 2-methylfuran through the HDO reaction with furfuryl alcohol being identified as the likely intermediate. Similar preferential interaction of the C=O group over the furan ring is also confirmed on SiO 2-supported FeNi bimetallic catalysts. The similar trends observed on model surfaces and supported catalysts demonstrate the feasibility of using single crystal surfaces to identify precious-metal-free bimetallic catalysts for biomass conversion.

Hydrodeoxygenation (HDO) is an important reaction for converting biomass-derived furfural to value-added 2-methylfuran, which is a promising fuel additive. In this work, the HDO of furfural to produce 2-methylfuran occurred on the NiCu bimetallic surfaces prepared on either Ni(111) or Cu(111). The reaction pathways of furfural were investigated on Cu(111) and Ni/Cu(111) surfaces using density functional theory (DFT) calculations, temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS) experiments. These studies provided mechanistic insights into the effects of bimetallic formation on enhancing the HDO activity. Specifically, furfural weakly adsorbed on Cu(111), while it strongly adsorbed on Ni/Cu(111) through an η 2 (C,O) configuration which led to the HDO of furfural on Ni/Cu(111). The ability to dissociate H 2 on Ni/Cu(111) is also an important factor for enhancing the HDO activity over Cu(111).

Skin undergoes degenerative changes as it ages, which include the loss of elasticity, reductions in the epidermal thickness and collagen content, elastic fiber degeneration, and increased wrinkling and dryness. Skin aging can be significantly delayed by the administration of estrogen. Estrogen deficiency following menopause results in atrophic skin changes and the acceleration of skin aging. Estrogen administration has positive effects on human skin by delaying or preventing skin aging manifestations, but the use of estrogen replacement is a risk factor for breast and uterine cancer. Phytoestrogens are a large family of plant‐derived molecules possessing various degrees of estrogen‐like activity; they exhibit agonist or antagonist estrogenic properties depending on the tissue. These molecules could be ideal candidates to combat skin aging and other detrimental effects of hypoestrogenism. In this paper, we review the effects of phytoestrogens on human skin and the mechanisms by which phytoestrogens can alleviate the changes due to aging.

Epidemiological studies on the impact of fish consumption on coronary heart disease (CHD) incidence have shown inconsistent results. In addition, in terms of CHD mortality, although previous meta-analyses showed that fish consumption reduces the risk of CHD, six newly incorporated studies show that fish consumption has no impact on CHD. Therefore, the results still need to be verified. The purpose of this study is to quantitatively evaluate the impact of fish consumption on CHD incidence and mortality. Relevant studies were identified from PubMed, Web of Science, and Embase databases up to October 2019. The multivariate-adjusted relative risks (RRs) for the highest versus the lowest fish consumption categories and the 95% confidence intervals were computed with a random-effect model. A restricted cubic spline regression model was used to assess the dose–response relationship between fish consumption and CHD incidence and mortality. Forty prospective cohort studies were incorporated into research. Among them, 22 studies investigated the association between fish consumption and CHD incidence (28,261 cases and 918,783 participants), and the summary estimate showed that higher fish consumption was significantly associated with a lower CHD incidence [RR: 0.91, 95% CI: (0.84, 0.97); I2 = 47.4%]. Twenty-seven studies investigated the association between fish consumption and CHD mortality (10,568 events and 1,139,553 participants), and the summary estimate showed that higher fish intake was significantly associated with a lower CHD mortality [RR: 0.85, 95% CI: (0.77, 0.94); I2 = 51.3%]. The dose–response analysis showed that the CHD incidence and mortality were reduced by 4%, respectively, with a 20 g/day increment in fish consumption. This meta-analysis indicates that fish consumption is associated with a lower CHD incidence and mortality.

The conversion of lignocellulosic biomass‐derived oxygenates into renewable fuels and chemicals requires the control of bond‐scission sequences. For example, selective CO/CO bond scission is needed to reduce the oxygen content and thus increase the energy density to produce renewable fuels. On the other hand, the control of CC bond scission is desired for producing H2 and suppressing side products from CO/CO bond‐scission reactions. In this review, recent advances in the utilization of bimetallic and metal carbide catalysts that demonstrate enhanced performance and/or low cost for the selective CC and CO/CO bond‐scission reactions, are summarized. Furthermore, the importance of combining density function theory (DFT) calculations, microkinetic modeling, and ultrahigh vacuum (UHV) experiments on single‐crystal model surfaces with reactor evaluations over the corresponding powder catalysts is illustrated. General trends and future opportunities for the control of bond‐scission sequences of biomass‐derived oxygenates are also discussed.

Designing catalysts with high activity and selectivity for biomass conversion to fuels and chemicals requires the understanding and controlling of the bond scission mechanism in biomass derivatives. In the current study, ethylene glycol, the smallest polyol from cellulose with the same atomic C/O ratio as C5 and C6 sugars, is employed as a surrogate molecule for controlling the bond scission sequence of O−H, C−H, C−O, and C−C bonds. A promising methodology for catalyst design is established in this work by constructing a microkinetic model to predict the activity and selectivity for ethylene glycol transformation reactions on molybdenum carbide (Mo 2 C) and metalmodified Mo 2 C surfaces, followed by supplementing the theoretical prediction with temperature program desorption (TPD) and high-resolution electron energy loss spectroscopy (HREELS) experiments on model surfaces. The fundamental insights from the theoretical approach and experimental results thus helps to guide the catalyst design and reduce the number of catalyst candidates in future experiments.