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In an acetylene hydrogenation reactor, the slowly falling catalyst activity affects ethylene plant performance in an operating cycle. To maximize the integral economic benefit in a regeneration cycle or achieve the longest regeneration cycle, the full cycle operation optimisation must be a long time-scale dynamic optimisation for which the method of control vector parameterization is adopted. Because of various uncertain disturbances, some distances must be reserved for process constraints and the desired effect of full cycle optimisation is hardly fully achieved. Thus, based on the strictly slowly-time-varying catalyst deactivation model, the operation margin consumption is estimated. Furthermore, a modified full cycle operation optimisation strategy is presented which takes the operation margin consumption as additional constraints. To obtain the maximum integral economic benefit or the longest regeneration cycle, we present a realizable full cycle optimized operation plan that considers the sufficient operation space reserved for uncertain disturbances.

Carbon black is used as conducting support for NiO nanoparticles, and noble metal particles are well dispersed on NiO/C with an average diameter of 4–8 nm. Benefiting synergistic effect, NiO/C by adding noble metal exhibits superior electrochemical activity and excellent stability for oxygen evolution reaction in water splitting. A catalyst with a weight ratio of Au to NiO of 1:2 gives the best performance. Onset potential on the Au-NiO(wt 1:2)/C electrode shifts more negatively than that on Pt-NiO(wt 1:2)/C and Pd-NiO(wt 1:2)/C, and onset potential on the Au-NiO(wt 1:2)/C electrode is lower than that on the other electrodes.

Three-dimensional (3D) manganese oxides consisted of tetragonal phase Mn3O4 and α-MnO2 with different morphology have been directly grown vertically on Ti foil by a simple electrochemical method without any template and used as the catalysts for oxygen evolution reaction (OER). The results show that manganese oxides with different morphology show high activity and good stability for OER and the manganese oxide (MnOx) nanowire arrays obtained at 70 °C show higher activity and better stability than MnOx with cotton wool structure and MnOx nanosheet arrays.

In view of the problems encountered in practical application of work-over rig original power "Change from oil to electricity", we propose a scheme for control system of electric work-over rig based on AC/DC hybrid micro-grid. Then take Boost circuit of Bidirectional Buck-Boost DC/DC as an example to design IDA controller. Finally, using the above research results, we design the electric work-over rig control system, and describe control method about energy balance control in this system.

Many studies have suggested that VSMC (vascular smooth muscle cell) apoptosis plays a key role in destabilization and rupture of atherosclerotic plaques. Therefore protection for VSMCs from apoptosis is a promising approach to stabilize 'vulnerable' lesions. However, the mechanisms as to why VSMCs in the fibrous cap often appear as profilerated in early stages, but turn apoptotic in advanced stages, are still unknown. In the present study, using RNAi (RNA interference) technology and a CaN (calcineurin) antagonist, the correlation between CaN and RANTES (regulated upon activation, normal T-cell expressed and secreted) in cultured rat apoptotic VSMCs stimulated by IFNgamma (interferon gamma; 20 ng/ml) and CD40L (CD40 ligand; 100 ng/ml) was investigated. RANTES released from VSMCs in each group was measured by ELISA and its mRNA in VSMCs was determined by RT (reverse transcription)-PCR. The total activity and expression of CaN in VSMCs were detected by the zymochemistry method and Western blot analysis respectively. From the results of the present study it can be hypothesized that an elevated CaN concentration in endochylema, by the CD40-CD40L signal pathway, induces VSMC apoptosis accomplished by the overexpression of RANTES. Therefore RANTES is a potential target for treating vulnerable atherosclerotic plaques owing to its crucial downstream regulating role in CaN-dependent VSMC apoptosis.

Background and Aims There is an imbalance between Th1 and Th2 in the development and progression of atherosclerosis and in patients with acute coronary syndrome (ACS) including acute myocardial infarction (AMI) and unstable angina. T helper cell type 3 (Th3), which primarily secretes transforming growth factor beta-1 (TGF-β1), has been shown to inhibit both Th1 and Th2 cells. The present study was designed to investigate whether Th3 cells are involved in plaque destabilization and the onset of ACS. Methods Ninety one patients who underwent diagnostic catheterization were classified into four groups (AMI group, unstable angina group, stable angina group and chest pain syndrome group). The cell frequencies of Th1, Th2 and Th3 were detected using flow cytometry, and the concentrations of their related cytokines IFN- γ , IL-4 and TGF-β1 were studied by ELISA. Results Apart from the imbalance between Th1 and Th2, results revealed a significant decrease in peripheral Th3 number and levels of TGF-β1 in patients with ACS as compared with those in patients with stable angina and chest pain syndrome ( p Conclusions Downregulation of Th3 cells in patients with ACS may play a potential role in plaque destabilization and the onset of ACS.