Search

In order to develop a functional ionic liquid catalyst with good stability and excellent catalytic effect on the organic reactions under alkaline conditions, a magnetic nanocatalyst of tertiary amine ionic liquid incorporated Fe3O4 was prepared and applied in the Knoevenagel reaction, the catalyst exhibits good stability and excellent catalytic performance in the Knoevenagel reaction, short reaction time and excellent yields of Knoevenagel products were obtained. In addition, the catalyst can be separated rapidly under the external magnetic force and reused for 8 times without significant loss of activity. Through the activity comparison of the catalyst and the FTIR, XRD, TG, VSM, SEM, TEM, and BET analysis, the excellent catalytic effect of the catalyst may be attributed to the synergistic effect of the catalytic action of tertiary amine, ionic liquid structure and the small size and strong surface effect of nanoparticles.

Magnetic nano catalysts are widely used in various organic reactions due to their characteristics of magnetic separation and recycling. Magnetic Fe3O4@SiO2 nano catalyst modified by 1, 8-diazabicyclo [5.4.0]-7-undecene (DBU) was prepared and applied in the Knoevenagel reaction. The results showed that the catalyst has an excellent effect on the Knoevenagel reaction, which not only improves the reaction rate and yield, but also it can be easily separated from the reaction mixture driven by external magnetic force. Furthermore, the catalyst can be recycled 10 cycles with no loose of the catalytic activity.

Novel ionic liquid N-(2-hydroxy-ethyl)-DBU bromide ([HyEtDBU]Br), based on 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU) and 2-bromoethanol, was introduced as catalyst for Knoevenagel condensation. Comparing with other non-hydroxyl ionic liquids, [HyEtDBU]Br showed a better catalytic activity, the hydroxyl group linked on the ionic liquid played an important role in facilitating the Knoevenagel condensation reaction. In the presence of [HyEtDBU]Br-H2O-DABCO composite system, the corresponding Knoevenagel adducts were obtained in good to excellent yields within short times in all cases examined, the procedure is simple and the desired products could be easily separated and purified without any requirement of column chromatographic purification. The use of water as the reaction medium makes the process environmentally benign. The composite system [HyEtDBU]Br-H2O can be recycled eight times without activity loss.

The spherical head supporting part is an essential part which connects the shell of one kind of front drive axle body, wheel driving and steering, braking structure and other key parts of the body, and to assume the function of load-bearing, steering, driving, braking and so on, it also has an important implications on the load-bearing capacity, steering capability, reliability, service life and safety of the front drive axle. This article mainly introduce the manufacture of the spherical head supporting part which the both ends are thick while the middle part is thin, inside the part is empty, both the inner and outer part are spherical and has special structures. Mainly introduce the technology of dual spherical head forging, hard turning, trundle processing that are used in the manufacture of this spherical head supporting part. Overcome the challenge of dual spherical head forging technology, both ends with reverse fillet shaft induction hardening surface manufacture technology. Smoothly finished debugging and manufacturing the spherical head supporting part. Also finished the test of the front drive axle. The spherical head supporting part’s function, strength, stiffness, reliability, fully meet the requirements of bench test, reliable, and fully meet the demand of the vehicle matching.

Recent studies showed that hydrogen can be used as an effective radioprotective agent through scavenging free radicals. This study was undertaken to evaluate the radioprotective effects of hydrogen on immune system in mice. H(2) was dissolved in physiological saline using an apparatus produced by our department. Spleen index and histological analysis were used to evaluate the splenic structural damage. Spleen superoxide dismutase, GSH, MDA were measured to appraise the antioxidant capacity and a DCF assay for the measurement of radical oxygen species. Cell apoptosis was evaluated by an Annexin V-FITC and propidium iodide staining method as well as the apoptotic proteins such as Bcl-2, Bax, caspase-3 and c-caspase-3. CD4+ and CD8+ T cells subtypes were detected by flow cytometry with FITC-labelled antimouse CD4 and PE antimouse CD8 staining. Real-time PCR was utilized to determine the CD4+ T cell subtypes and related cytokines. Our study demonstrated that pre-treatment with H(2) could increase the spleen index and attenuate the radiation damage on splenic structure. Radical oxygen species level was also reduced by H(2) treatment. H(2) also inhibited radiation-induced apoptosis in splenocytes and down-regulated pro-apoptotic proteins in living mice. Radiation-induced imbalance of T cells was attenuated by H(2). Finally, we found that H(2) could regulate the polarization of CD4+ T cells and the level of related cytokines. This study suggests H(2) as an effective radioprotective agent on immune system by scavenging reactive oxygen species.

The present study was designed to prospectively investigated the prostaglandin (PG) levels and extent of peritumoral edema in 30 cases of glioma by using methods of radioimmunoassay and imaging. Both TXB2 and 6-keto-PGF1 alpha levels in all glioma groups went up over that in the control group. TXB2 level and ratio of TXB2/6-keto-PGF1 alpha were markedly increased with the extent of tumor malignancy. Water concentration in anaplastic astrocytoma and glioblastoma were significantly elevated. Difference in TXB2 level and TXB2/6-keto-PGF1 alpha ratio among three edema grades were statistically significant. TXB2 level and ratio of TXB2/6-keto-PGF1 alpha were closely correlated with water concentration (r1 = 0.53, r2 = 0.72, P0.01). Our findings suggested that the metabolism of PG in glioma were in the state of disorder, and that the imbalance between PGI2 and TXA2 may be one of factors which affect the formation of peritumoral edema.