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In the tandem hydroformylation–acetalization catalyzed by an Ir-catalyst, water as the hydrogen source can inhibit the hydrogenation of olefins, and a catalytic amount of AlCl3 as a promoter can promote acetalization.

The physicochemical characteristics of a new composite oxygenated fuel named oligomeric polyoxymethylene dimethyl ether and DMM10 (the blend of this fuel and conventional diesel oil with 10% in volume) were analyzed. The power performance, fuel economy, combustion characteristics and exhaust gas emission of a four strokes, direct injection, turbocharged and intercooled diesel engine fuelled with DMM10 and diesel fuel were analyzed and compared. The results show that in comparison to original diesel engine, when the engine fuelled with DMM10 blend fuel, the power performance remains unchanged; BSEC decrease slightly, smoke emission decreases obviously and its decrease rate is up to 72%.

Due to the good chemical properties, polyoxymethylene dimethyl ethers (DMMn) are regarded as an outstanding additive component of diesel fuel, which are efficient in reducing the formation of soot during the combustion when added to diesel fuel. The properties, synthetic methods and application of DMMnare summarized and introduced in this paper. Furthermore, the development and application prospects of DMMnin future are presented.

Carbon nanotube-supported Co-Mo catalysts with different Co/Mo atomic ratio were prepared by pore volume impregnation. These catalysts were used in the hydro-cracking reaction of Gudao vacuum residue, and the catalytic properties were compared with γ-Al 2 O 3 -supported Co-Mo catalysts under the same reaction conditions. It was found that the catalytic properties of Co-Mo/carbon nanotube (CNT) catalysts are inferior to Co-Mo/γ-Al 2 O 3 . However, the Co/Mo atomic ratio has great effect on the catalytic activity of Co-Mo/CNT; the Co-Mo/CNT catalyst with Co/Mo atomic ratio of 0.5 has the best catalytic properties, whereas for Co-Mo/γ-Al 2 O 3 catalyst the best Co/Mo atomic ratio is 0.35.

To observe the effect of electroacupuncture (EA) and moxibustion-like thermal stimulation with different temperatures at "Zusanli" (ST 36) on pain reactions in transient receptor potential vanilloid type 1 knock-out (TRPV 1 -/-) mice so as to study its mechanisms underlying analgesia.Ten C 57 BL/6 mice and 10 TRPV 1 -/- mice were respectively divided into control and TRPV 1 -/- groups. EA (0.3 mA, 1.0 mA, 3.0 mA) or thermal water-bath (38 degrees C, 43 degrees C, 46 degrees C) stimulation was applied to the right ST 36 for 20 min and 10 min, respectively. Mechanical and thermal pain thresholds of the bilateral paws were detected before and immediately after stimulation, and 5 min after EA stimulation at 0.3 mA, 3.0 mA and thermal water-bath stimulation at 38 degrees C, 46 degrees C, separately.(1) The thermal threshold was significantly higher in TRPV 1 -/- mice than in C 57 BL/6 mice (P0.001). (2) In C 57 BL/6 mice, both homolateral and contralateral mechanical and thermal pain thresholds were significantly increased following 1.0 mA, 3.0 mA EA, and 43 degrees C and 46 degrees C thermal stimulation of the right Zusanli (ST 36) (P0.05, P0.01, P0.001); while only homolateral mechanical and thermal pain thresholds were increased after 0.3 mA EA and 38 degrees C thermal stimulation of ST36 (P0.05, P0.01). In TRPV 1 -/- mice group, both homolateral and contralateral mechanical and thermal pain thresholds were significantly increased by 3.0 mA EA stimulation of ST 36 (P0.05, P0.01). Bilateral mechanical thresholds and homolateral thermal threshold were significantly increased by 1.0 mA EA stimulation of ST 36 (P0.05, P0.01), while only homolateral mechanical and thermal pain thresholds were increased by 0.3 mA EA, and 43 degrees C and 46 degrees C thermal stimulation (P0.05, P0.01). Additionally, only the homolateral mechanical threshold was increased by 38 degrees C thermal stimulation (P0.05). (3) The mechanical and thermal pain thresholds of the bilateral limbs were increased to some extent in TRPV 1 -/- mice compared with those of C 57 BL/6 mice following EA and thermal stimulation of the right ST 36. (4) Five minutes after 0.3 mA, 3.0 mA EA and 38 degrees C, 46 degrees C thermal water-bath stimulation, both mechanical and thermal pain thresholds recovered to their baseline levels in both TRPV 1 -/- and C 57 BL/6 mice.Both EA and thermal stimulation of the right ST 36 can raise mechanical and thermal pain thresholds in TRPV 1 -/- and C 57 BL/6 mice, but needing a stronger stimulation in TRPV 1 -/- mice, suggesting an involvement of TRPV 1 receptors in analgesia.

To observe the inhibitory effect of auricular concha transcutaneous electrostimulation (ACTES) of different frequencies and duration on acute seizures in epilepsy rats so as to select a better stimulating parameter for relieving epilepsy.According to the stimulation duration of ACTES, 44 Sprague-Dawley rats were randomized into: 30 s, 5 min, 10 min, and 30 min groups. Epilepsy model was duplicated by intraperitoneal injection of PTZ (pentylenetetrazol, 50 mg/kg). Cerebral field potentials delivered from the fixed 4 recording electrodes array (A-P: -3 -6, L: 4 - 6, H: 1. 5) and reference electrode (a fixed screw) touching the cerebral dura surface were recorded using a data acquisition system (Cerebus 5.0 system). Transcutaneous electrostimulation (1 mA, duration 500 micro(s)) of frequency 2 Hz, 20 Hz and 100 Hz was applied to auricular concha by using an electric stimulator. The anti-epileptic effects of ACTES were evaluated by using the duration and rate of seizure suppression.(1) The anti-epileptic effect of 20 Hz -ACTES was markedly longer than those of 2 Hz and 100 Hz in the duration of seizure suppression (P0.05). (2) After 2 Hz-ACTES, the anti-epileptic effects (duration and inhibitory rate) in 30 s-stimulation group were markedly longer than those of the 5 min-, 10 min- and 30 min-stimulation groups (P0.01, P0.05). (3) After 100 Hz-ACTES, the anti-epileptic effects (duration and rate of seizure suppression) in the 30 min-stimulation group were markedly longer than those in the 30 s-, 5 min- and 10 min-stimulation group (P0.01, P0.05).ACTES at 20 Hz can effectively lessen epileptic seizures, and under fixed stimulating frequencies of 2 Hz and 100 Hz, the anti-epileptic effects of 30 s ACTES and 30 min-ACTES are obviously better in epilepsy rats.

To observe the effect of electroacupuncture (EA) on cortical spreading depression (CSD) and contents of plasma calcitonin gene-related peptide (CGRP) and substance P (SP) in migraine rats.Thirty male SD rats were equally randomized into control, model and EA groups. Migraine model was established by topical application of KCI (3 mol/L) immersed in a piece of filter paper to the cerebral cortex (parietal lobe, 6 mm posterior to the Bregma and 5 mm to the sagital fissure) after exposure of the skull (in reference to Michael' method). KCI stimulation evoked CSD potentials (3 mm rostral to the Bregma, and 2 mm to the sagital fissure) were recorded by using a glass microelectrode. For rats of control group, filter paper containing 0.9% NaCl was applied to the same parietal cortex area. EA (1 mA, 2 Hz/100 Hz) was applied to bilateral "Yanglingquan" (GB 34) and "Taichong" (LR 3) for 30 min. The contents of plasma CGRP and SP were assayed by radioimmunoassay.CSD was induced 3-5 min after application of KCI to the parietal lobe. The average amplitude of model group was (-25.13 +/- 1.23) mV, and that of EA group was (-19.19 +/- 1.53) mV, displaying a significant reduction of CSD amplitude after EA (P0.01). Comparison among 3 groups showed that both plasma CGRP and SP contents in model group were significantly higher than those of control group (P0.001, P0.01), while compared with model group, plasma CGRP and SP levels in EA group decreased considerably (P0.05, P0.001), suggesting an inhibitory effect of EA on pain-producing substance.EA of GB 34 and LR 3 can effectively suppress KCI provoked cortical spreading depression and plasma CGRP and SP levels in the rat, which may contribute to its effect in relieving migraine in clinic.