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Objective: To investigate the effects of intrauterine infection in different periods on the placenta and endometrial blood vessel formation of pregnant rats and the growth and development of fetal rats.Methods: According to the random number table method, 32 pregnant rats were divided into the early infection group, the mid-term infection group, the late infection group and the control group, with 8 rats in each group. On the 3rd, 9th and 15th day of pregnancy, lipopolysaccharide was injected intraperitoneally to construct intrauterine infection models. The pregnant rats in the control group were intraperitoneally injected with the same dose of 0.9% sodium chloride solution. On the 18th day of pregnancy, the inflammatory factors [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], the blood vessel density of placenta and endometrium in the placental tissues of pregnant rats, dead fetus + absorbed fetus, the inflammatory factors IL-6, TNF-α and oxidation reaction indicators [malondialdehyde (MDA) and myeloperoxidase (MPO)] in the fetal rat lung and brain tissues were detected.Results: The changing trend of IL-6 and TNF-α levels in the placental tissues of pregnant rats with intrauterine infection in different periods was: the control group < the late infection group < the mid-term infection group < the early infection group, the differences were statistically significant (p the late infection group > the mid-term infection group > the early infection group, the differences were statistically significant (p < .05). The blood vessel density of placenta and endometrium, the mean number of fetuses, brain coefficient and lung coefficient in the late infection group were significantly increased in comparison with the early infection group and the mid-term infection group. The total number and the ratio of dead fetus + absorbed fetus, the levels of IL-6, TNF-α, MDA and MPO in brain and lung tissues were significantly reduced, and the differences were statistically significant (p < .05). The blood vessel density of placenta and endometrium, brain coefficient and lung coefficient of pregnant rats in the mid-term infection group were significantly increased in comparison with the early infection group, and the differences were statistically significant (p < .05). There was no statistically significant difference in the other indicators between the two groups (p > .05).Conclusions: Intrauterine infection in different periods can inhibit placental and endometrial angiogenesis, and affect the survival rate of fetal rats and the growth and development of brain and lung. The reason may be related to the aggravation of fetal inflammatory responses and oxidative stress. The earlier the intrauterine infection occurs, the severer the adverse effects on the fetal rats will be.

A magnetically recyclable carbon nitride supported Au–Co nanoparticles (Au–Co@CN) displayed exceedingly high photocatalytic activity for hydrolysis of aqueous ammonia borane (NH3BH3, AB) solution. Combined with a synergetic effect between Au and Co nanoparticles, the Motty–Schottky effect at the metal–semiconductor interface remarkably facilitated the catalytic performance of the Au–Co@CN catalyst on the hydrolysis of AB. The TOF value of Au–Co@CN catalyst is 2897 mol H2 mol–1 metal h–1 at 298 K under visible light irradiation, which is more than 3 times higher than that of the benchmarked catalyst, PVP-stabilized Au@Co nanoparticles.

The chiral mono-faced binaphthyl strapped porphyrins were synthesized and1H NMR characterized. Asymmetric epoxidation of olefins such as styrene derivatives and trimethylsilyl ethylene with iodosobenzene as oxidant was achieved by using the iron complex as catalyst in the presence of a nitrogen ligand. Enantiomeric excess (ee) of 80% and yield of 88% were measured for the epoxidation of styrene in the presence of 4-phenyl pyridine. The coordination capability of nitrogen ligands to catalysts measured by UV-vis spectrophotometric titrations evidence that the unstrapped face of the mono-faced catalyst is blocked by the nitrogen ligand coordination to the iron ion of the catalyst.

Two series of p/p and o/o type iron(III)-metal-free porphyrin dimers were synthesized and characterized. The dimers consist of a ferric porphyrin and a free-base porphyrin, covalently linked with an alkoxy chain - O ( CH 2)n O -(n = 2–10) at the para and ortho position of two phenyl rings. The ferric paramagnetic effect and ring current effect on these dimers were discussed by 1 H NMR study; vibration modes sensitive to the conformations of the dimers were investigated from IR spectra; the electron density and spin state of ferric ion were examined using XPS and EPR spectroscopy. The catalytic activities of p/p and o/o type dimers on the hydroxylation of cyclohexane were studied under mild conditions. As a chemical mimic model of Cyto. P450, these porphyrins exhibit higher catalytic activities than the corresponding monomer FeTPPCl . With increase of the carbon numbers of alkoxy chain, the catalytic activity order of p/p dimers is C 2 < C 3 < C 4 < C 5 < C 6 > C 8 > C 10, the corresponding order of o/o dimers is C 2 > C 4 > C 6 > C 8 > C 10. Catalytic results of dimers are shown to strongly depend on their special conformation equilibrium, which affect the steric hindrance and electron transfer between two porphyrin rings.

A series of p/p type iron(III)–iron(III) porphyrin dimers and corresponding zinc(II)–zinc(II) porphyrin dimers covalently linked by a flexible alkoxy chain (–O(CH 2 ) n O–, n =2–10) have been synthesized and characterized. The hydroxylation of cyclohexane catalyzed by iron(III)–iron(III) porphyrin dimers with molecular oxygen under mild conditions are reported, 1 eq. of bidentate ligand DABCO (1,4-diazobicyclo[2,2,2] octane) is added exactly as axial ligand to the catalytic system. The catalytic activities of these dimers are supposed to be related to the special conformations formed by porphyrin dimers and DABCO. By using 1 H -NMR, the conformation equilibrium of corresponding zinc(II)–zinc(II) porphyrin dimers and their binding behavior with 1 eq. DABCO has been discussed in detail. It has been proven that the higher catalytic activities of the catalytic system mainly result from the formation of the ternary sandwich complexes of iron(III)–iron(III) porphyrin dimers with DABCO.

A new chiral binaphthyl-strapped iron-porphyrin 4 b that exhibits unprecedented catalytic activity toward the enantioselective epoxidation of terminal olefins was synthesized. Typical enantiomeric excesses (ee) of 90 % were measured with a maximum of 97 % for the epoxidation of styrene, whereas the turnover numbers (TON) averaged 16000.

Water-soluble porphyrins can be phase transferred by the hyperbranched multiarm copolymer PEI-PZLys; good catalytic activities and recyclabilities were observed for oxidation catalyzed by the encapsulated porphyrins.