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Fetal overgrowth, termed fetal macrosomia when birth weight is greater than 4000 grams, is the major concern in the treatment of gestational diabetes mellitus (GDM). However, to date, the underlying mechanisms of fetal macrosomia have not been understood completely. Placental lipid metabolism is emerging as a critical player in fetal growth. In this study, we hypothesized that fatty acid transport and metabolism in the placental tissue was impaired in GDM women, dependent on fetal sex. To test this hypothesis, we analyzed the incidence of GDM, fetal macrosomia, and obesity in a large cohort consisting of 17995 pregnant subjects and majority of subjects being Hispanic/Latinx, and investigated expression of genes related to lipid transport and metabolism in placenta from obese women with or without GDM, and with or without fetal macrosomia. The main findings include: 1) There is a higher incidence of GDM and obesity in Hispanic subjects compared to non-Hispanic subjects, but not fetal macrosomia; 2) Expressions of most of genes related to placental lipid transport and metabolism are not altered by the presence of GDM, fetal macrosomia, or fetal sex; 3) Expression of FABP4 is increased in obese women with GDM and fetal macrosomia, and this occurred in male placentas; 4) Expression of LPL is decreased in obese women with GDM despite fetal macrosomia, and this occurred in male placentas; 5) Expression of ANGPTL3 is decreased in obese women with GDM and fetal macrosomia, but is not altered when fetal sex is included in the analysis. This study indicates that there is race disparity in GDM with higher incidence of GDM in obese Hispanic women, although fetal macrosomia disparity is not present. Moreover, altered placental lipid transport may contribute to fetal overgrowth in obese women with GDM.

Titania-silica monoliths with bicontinuous macropores and ordered mesopores were successfully prepared by a double-template technique. The influence of reactants on pore structures and Ti content was studied in detail. The results demonstrated that acid concentration in starting compositions has a great effect on morphologies of the final samples. Besides, it is also found that the changing of water-soluble organic polymers amount and triblock copolymers amount could adjust the pore size of macropores and the order degree of mesopores respectively. Moreover, the addition of fluoride benefits much more titanium atoms incorporate into the framework of silica. Compared with Ti-SBA-15, the hierarchical titania-silica monolith showed better performance on catalytic reaction of large molecules such as epoxidation of cyclohexene to cyclohexene oxide with isopropyl benzene hydroperoxide.

The catalytic performance of the hierarchical beta zeolite prepared via the dry gel conversion method was compared with that of the conventional beta zeolite for transalkylation of diisopropylbenzene with benzene. The results indicate that diisopropylbenzene conversion decreases from 74% to 29% after a reaction time of 32 h over the conventional beta zeolite. However, for the hierarchical beta zeolite, diisopropylbenzene conversion still remains above 60% after 32 h under the same reaction conditions. In order to learn the factors leading to the difference in catalytic activity, we studied pore structure, crystal size and acidity of the hierarchical beta zeolite and the conventional beta zeolite and we discussed their effects on catalytic activity. The results reveal that the better activity and stability of the hierarchical beta zeolite is mainly due to the presence of meso/macropores and nanocrystals for the liquid transalkylation reaction.

Aluminosilica monoliths with bicontinuous macropores and interconnected mesopores were successfully prepared by a double-template technique. The influence on monolithic pore structures and acidic properties based on aluminum variety was studied in detail, which demonstrated that aluminum addition and water amount in starting compositions had great effects on the formation of hierarchical pore system with bicontinuous macropores and interconnected mesopores. In addition to bicontinuous macropores and plenty of mesopores, the obtained aluminosilica monoliths also possessed considerable acid sites for catalysis. And such aluminosilica monolith with proper acidity and good diffusion showed best performance on catalytic reaction of large molecules such as the cracking 1,3,5-triisopropylbenzene compared with other aluminosilica monolith.

Co-modified HZSM-5 zeolite catalysts were prepared by ion exchange with Co(CH3COO)2 solution, and incipient wetness impregnation with aqueous solutions of Co(NO3)2 and Co(CH3COO)2, respectively. The catalysts were characterized by N2-adsorption, NH3–TPD, FTIR and adsorption of m- and p-cresol. The catalytic performance for the synthesis of pyridine and picolines from aldehyde-ammonia condensation was tested. It shows that Co disperses in the zeolite pores for the ion exchanged samples, while Co deposits mainly on the external surface for the samples prepared by impregnation of Co(CH3COO)2, which results in a narrowing of the pore mouth. NH3–TPD and pyridine-FTIR measurements indicate that the total acidity and the Lewis acidity of the catalysts increased with the decrease of Bronsted acidity among the samples. The samples prepared by impregnation with Co(CH3COO)2 have the highest yield of the desired products among all the samples tested. This is attributed to the change of surface acidity and the reduction of the pore-mouth of the zeolite.

A novel hierarchical SAPO-34 monolith was prepared by the dry gel conversion of the amorphous silicoaluminophosphate monolith. The obtained material possesses macropores and mesopores besides micropores. The macroporous framework of the hierarchical SAPO-34 is constructed by interconnected spherical aggregates of cubic SAPO-34 crystals and mesopores is formed by the close stacking of cubic SAPO-34 crystals. Catalytic tests show that the hierarchical SAPO-34 possesses high catalytic activity compared with the conventional microporous SAPO-34 for methanol conversion to light olefins (MTO) reaction. The better activity is mainly assigned to the existence of cubic SAPO-34 crystals and the hierarchical porosity.