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In this paper, the influencing factors in the process of alkali leaching of refractory zinc oxidize ores were studied. The influence of the particle size, reaction temperature, leaching time, alkali concentration and liquid-solid ratio on the leaching efficiency of zinc were investigated via leaching tests. The results indicate that the particle size has little influence on the leaching efficiency of zinc while the influences of other factors are larger. The optimal leaching condition is: the reaction temperature is 80 °C, the alkali concentration is 4.5 mol/L, and the leaching time is 1.5 h as well as the liquid- solid ratio is 10:1. In such conditions, the leaching efficiency can reach 82.22%.

The maximum intensity of Lushan earthquake in Sichuan Province is IX degree and the area of influence regions above VI degree is 18,682 square kilometers, which resulting in a large number of buildings destructed. Based on seismic field data collected from works of damage investigation, loss assessment and intensity survey in the first time, seismic damage phenomena and characteristics as well as damage photographs for different structural types of buildings are summarized and analyzed, and some suggestions are put forward to structure anti-seismic designs.

Carbon decomposition of liquor afger desilication from nephine was investigated, aluminium oxide was prepard by anneal of Al (OH)3 separated out from carbon decompositon, and analysis of radionuclide of both above process was performed. The results show decomposition rate of sodium aluminate can be obtained when experiments of carbon decomposition of liquor after desilication using CO2 of hight concentration, and it is beneifit for the crystal growth of Al (OH)3, filtration and separation. Great mass of nuclide exists in the mother solution of carbon decomposition, and few into Al (OH)3, which could be regarded as wiout radioactive contamination. .

The N-heterocyclic carbene catalyzed stereoselective dimerization reactions of phthalaldehydes produced polyhydroxylated spiro- or fused indenones. The reaction pathways were dictated by the structures of NHC catalysts. Under the catalysis of a imidazole carbene, phthalaldehydes produced dihydroxylspiro[indene-2,1'-isobenzofuran]-3-ones in good to excellent yields, whereas a triazole carbene catalyzed reaction of phthalaldehydes afforded fully cis-trihydroxylindeno[2,1-a]inden-5-ones in high yields. This work not only provides a highly efficient method for the construction of valuable polyhydroxyl substituted indene derivatives that are not easily assembled by other synthetic means but also reflects the versatility of organocatalysis using N-heterocyclic carbenes.

In the presence of IMC, phthalaldehydes undergo efficient dimerization yielding spirocyclic indenones like (II).

Treatment of the title carbenes with aldehydes and DMAD results in formation of aminofurans such as (IV) and/or (V) depending on the nature of substituents and conditions used.

To investigate the effect of a new reactive oxygen metabolites (ROM) scavenger as immune adjuvant in NK cell-mediated killing effect on K562 cell, IL-2 and PHA were used to activate monocyte to produce ROM, and different concentrations of tiopronin as ROM scavenger was used in the cultivated systems with different ratio of monocytes plus NK cells and K562 cells, while histamine dihydrochloride (DHT) with different concentrations was used as positive control. The reuslts indicated that after IL-2 and PHA were supplemented in the cultivated systems mixing with NK cells and K562 cells as the E/T ratio was 10/1, the ROM production increased from 33.17 +/- 25.02 U/ml to 223.59 +/- 59.41 U/ml (P0.05) while K562 cell inhibition rate (KIR) increased from 65.56% to 85.89% (P0.05). When the monocytes as the E/MO ratios of 10/2, 10/5 and 10/10 were supplemented respectively, ROM production increased correspondingly (ROM production was 389.79 +/- 43.83 U/ml, 456.74 +/- 42.77 U/ml, 601.42 +/- 21.92 U/ml, respectively), and KIR was on the other round (KIR was 82.36%, 81.36%, 48.09% respectively). Tiopronin, DHT were used in the K562 + NK + MO + IL-2/PHA cultivated systems as the E/MO ratio was 10/2, the ROM production also decreased from 389.79 +/- 43.83 U/ml to -1.20 +/- 60.70 U/ml, 50.21 +/- 22.4 U/ml (P0.05), respectively, however KIR increased from 82.53% to 96.09% and 94.64% either (P0.05). Higher concentrations of tiopronin and DHT were used, ROM production decreased accordingly. There showed a reverse correlation between ROM production and KIR (r = -0.518). When E/MO ratio was 10/5 or 10/10, tiopronin at any testing concentration and DHT at the higher testing concentration could reduce the ROM production (P0.05), but did not improve KIR significantly (P0.05). Tiopronin was as good as DHT in ameliorating KIR (P0.05) and better than DHT in scavenging ROM (P0.05). It is concluded that (1) Monocytes are the major resources of ROM, and the ROM derived from monocytes can disable NK cells in killing neoplasm cells (K562 cells); (2) A new ROM scavenger, tiopronin, can scavenge ROM effectively, and reverse the ROM induced inhibition of NK cell-mediated killing of K562 cell in a certain extent. And tiopronin is better than DHT in scavenging ROM, and as good as DHT in up-regulating KIR. The new ROM scavenger tiopronin with less side effect may take the place of DHT as adjuvant during the adoptive immuno-therapy in leukemia.

To explore the mechanism of the effect of chronic intermittent hypoxia (CIH), an important pathophysiological state of sleep apnea syndrome (SAS), on cardiovascular system.Thirty male ICR mice were divided into three groups: an experimental group, an air mimic control group and a blank control group. Immunohistochemistry was used to examine the expression of hypoxia inducible factor-1alpha (HIF-1alpha) and inducible nitric oxide synthase (NOS-2) in the myocardial cells. Enzyme-linked immunosorbent assay (ELISA) was used to measure the plasma concentration of vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1).The expression of HIF-1alpha in myocardial cells of the experimental group significantly increased compared with that of the air mimic control group (t = 3.54, P0.05), and that of the blank control group (t = 2.92, P0.05). The expression of HIF-1alpha in myocardial cells of the air mimic control group was not significantly different from that of the blank control group (P0.05). The plasma concentration of VEGF of the experimental group [(9.57 +/- 1.41) ng/ml] was significantly higher than that of the blank control group [(8.10 +/- 0.62) ng/ml, q = 4.27, P0.05], and that of the air mimic control group [(8.32 +/- 0.99) ng/ml, q = 3.64, P0.05]. While the plasma concentration of ET-1 of the experimental group [(3.31 +/- 0.81) ng/ml] was significantly higher than that of the blank control group [(2.50 +/- 0.72) ng/ml, q = 3.64, P0.05], it was not significantly different from that of the air mimic control group [(2.69 +/- 0.43) ng/ml, P0.05]. There was no significant difference between the expression of NOS-2 in myocardial cells of all groups (P0.05).CIH enhances the expression of HIF-1alpha and its target gene products VEGF and ET-1, and therefore affects the cardiovascular system.

The nucleophilic reaction of ambident β-lactam carbenes with alkylphenylketenes is studied, which produces two types of spiro[β-lactam-2,1′-indene] derivatives in total yields of 55–89 %. This work not only provides the first example that ambident carbenes behave with high activity towards ketenes, but also developes the application of β-lactam carbenes in the construction of spiro-β-lactam compounds.