Density Functional Theory Investigation of the Sulfur-Iron Compound Formation Mechanism in Petrochemical Facilities.

In order to investigate the formation mechanism of hydrogen sulfide corrosion products in petroleum and petrochemical facilities, the interaction mechanism between iron oxides and H2S was studied by density functional theory (DFT). First, the adsorption of H2S on Fe2O3 clusters and Fe3O4 clusters was studied. The results indicated that H2S was more inclined to adsorb on the Fe site. After adsorption, the S-H bond changed from 1.356 to 1.360 Å in the gas phase, which was the main reason for the decomposition of H2S. On this basis, the reaction paths of Fe2O3 clusters and Fe3O4 clusters with H2S and the rate-determining steps of different reaction paths were calculated. The thermodynamic parameters and kinetic parameters of the rate-determining step of each path are analyzed. The results indicated that reaction path 1 of H2S and Fe2O3 clusters is the best reaction channel. The reaction will gradually form products such as S, H2O, and Fe2S2, which can release a total of 622.23 kJ/mol heat. The reaction path 2 of H2S and Fe3O4 clusters is the best reaction channel. The reaction will gradually form products such as S, H2O, and Fe3S2, which can release a total of 260.40 kJ/mol heat. Finally, the reaction paths of Fe2S2, Fe3S2, and S2 were further calculated, and it was observed that the products formed by hydrogen sulfide corrosion were easy to react with S2 to form sulfur-iron compounds with different iron-sulfur ratios. This is consistent with the corrosion products including FeS, FeS2, and Fe3S4 observed in the experiment. It lays a theoretical foundation for the subsequent study of the effect of associated elemental sulfur on the spontaneous combustion of sulfur-iron compounds.

Acupuncture improves the emotion domain and lipid profiles in women with polycystic ovarian syndrome: a secondary analysis of a randomized clinical trial.

Objective: This study aims to evaluate the effect of acupuncture on the emotion domain and metabolic parameters of Chinese women with polycystic ovarian syndrome (PCOS) by secondary analysis of a randomized clinical trial, conducted from 6 July 2012 to 7 October 2015. Method: In this study, we investigated the effects of acupuncture (458 patients) and sham acupuncture (468 patients) on metabolic parameters, serum ions, and all quality-of-life scale scores related to PCOS. The quality of life of patients was evaluated using five relevant scales, operated by the research assistant, namely, PCOSQ, SF-36, and ChiQOL, as well as Zung-SAS and Zung-SDS. Metabolic parameters and serum ions were measured. Results: A reduction in acne score, AN, Hcy, and LDL-C, and an increase in the level of lipoprotein α, Apo A1, and Apo A1/Apo B were observed in the acupuncture group after 4 months' intervention after adjusting clomiphene and reproductive outcome (p< 0.05). An increase in SF-36 total scores, RP and RE scores, ChiQOL total scores, and emotion domain scores was observed in the acupuncture group after 4 months' intervention, while PF and HT scores were decreased (adjusted p< 0.05). Those same changes were observed in sham acupuncture. Meanwhile, the serum levels of Ca, K, and Cl were elevated in the acupuncture group after the interventions (adjusted p< 0.005). There were no significant differences in HOMA-IR, MetS, FPG, FINS, HDL-C, TG, Apo B, and level of serum P, Mg, and Na. Also, no changes in BP, GH, VT, SF, physical form domain, and spirit domain were observed after treatment. Conclusion: Acupuncture can improve not only the emotional changes in SF-36 scores and ChiQOL scores, but also lipid metabolism, implying that it may have a correlation between emotional change and lipid metabolism. Furthermore, acupuncture can also regulate the changes of serum Ca, K, and Cl. Clinical trial registration: ClinicalTrials.gov, identifier NCT01573858.

The Effect of Age on IVF-ET Outcome in Infertile Patients with PCOS Based on Tiangui Theory in Chinese Medicine.

Objective: Our aim was to investigate the effect of age on the outcome of IVF-ET and ICSI in infertile PCOS patients under the guidance of Tiangui theory in traditional Chinese medicine. Method: This was a retrospective analysis of 532 infertile women with PCOS and 1,392 women with infertility due to tubal factors as the controls. All of the participants were divided into different age groups-aged 20-28 years, 29-35 years, and ≥36 years-according to the stages of female reproductive development in Tiangui theory as described in the Canon of Internal Medicine-Treatise of Ancient Natural Truth. We explored the effect of age on controlled ovarian hyperstimulation (including the initial dosage and duration of Gn and the estradiol level on the day of human chorionic gonadotropin administration); the numbers of retrieved oocytes, 2PN zygotes, and embryos; and the rates of fertilization, clinical pregnancy, abortion, live birth, and OHSS incidence. Results: Compared to controls, the maximum follicular diameter and the numbers of follicles with d ≥ 20 mm, retrieved oocytes, and 2PN zygotes were greater in the PCOS group with age >28 years (p < 0.05). The abortion rate of PCOS patients with age ≤28 years was higher than that of the controls. All PCOS groups and the control group showed reduced numbers of retrieved oocytes and live births with age. The difference in age was not significant in the PCOS groups but was significant in the control group (p < 0.05), and the trend in the PCOS groups was more gradual. Conclusion: The fertility of all subjects decreased with age, but PCOS patients decreased more slowly than in controls at the same age, which verified the applicability of the guiding principles of Tiangui theory in the clinic.