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Combined extraction of nickel and cobalt from nickel chloride solution using di (2-ethylhexyl) phosphonic acid(P204) and triisooctylamine(N235) as extractants was studied. The effects of organic phase P204 volume fraction, phase ratio, solution pH, saponification rate, organic phase N235 volume fraction, Cl- mass concentration, and reaction temperature on the purification and impurity removal of nickel chloride solution were investigated. The results show that after removing impurities by P204 extraction, N235 is used to extract cobalt and molybdenum from P204 raffinate, the mass concentrations of Ni2+ is 218.10 g/L, and the mass concentrations of Cu2+, Fe3+, Co2+, and Zn2+ in the residual solution 1.1, 1.2, 1.0 and 0.1 mg/L, respectively, under the conditions of 20% volume fraction of P204 in the organic phase of the P204 extraction and impurity removal process, VO/VA = 1.5/1, raw material solution pH = 3.5, saponification rate of 50%, reaction temperature of 40--50 °C, and N235 volume fraction of 16% in the organic phase of the N235 extraction process, VO/VA=1.2/1, Cl- mass concentration ≥280 g/L, reaction temperature of 40~50 °C, P204 Raffinate pH=3.0, and hydrochloric acid acidification concentration of 3 mol/L, which can meet the requirements of producing high quality electrodeposited nickel cathodes. [ABSTRACT FROM AUTHOR]

Based on the auction model formulated by Riley and Samuelson, by introducing the factors of online auction like the entry fee, the commission, the penalties and the stochastic arrival of bidders, online auctions' decision-make models of maximization of seller's expected revenue in open reserve price and private reserve price are investigated, respectively. The online auction's optimal open reserve price and optimal private reserve price are also investigated. The general form of optimal reserve price is given. By analyzing the optimal reserve price, it is shown that the sellers' optimal open reserve price is the same as the optimal private reserve Price. Moreover, the further comparison analysis between the optimal reserve price in online auction and the reserve price in traditional offline auction is made. The effect of the bidders' arrival rate on the optimal re-serve Price is discussed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of autophagy on exocrine function of pancreas in rats with acute sepsis, and to determine whether the mitochondrial coenzyme Q (Mito Q) can prevent exocrine dysfunction of pancreas mediated by autophagy., Methods: Experiment I: 30 Sprague-Dawley (SD) rats were randomly divided into three groups, with 10 rats in each group. All the rats were given lipopolysaccharide (LPS, 10 mg/kg) intraperitoneally, and Wortmannin (2 mg/kg), the specific inhibitor of autophagy (LPS + Wortmannin group), Mito Q (6.5 μmol/kg, LPS + Mito Q group), or the same volume of normal saline (LPS group) was respectively injected via the tail vein 1 hour later. Survival rate was assessed within 12 hours after LPS injection. Experiment II: another 100 male SD rats were randomly divided into ten groups with 10 rats in each group: namely control 4, 6 and 12 hours groups, LPS 4, 6 and 12 hours groups, and LPS + Wortmannin 4 hours group, Wortmannin 4 hours group, LPS + Mito Q 6 hours group, and Mito Q 6 hours group. The protocols of model reproduction and drug administration were the same as in the experiment I. Blood samples were collected at each time point, and the amylase content was determined with the velocity method. The levels of reactive oxygen species (ROS) in the pancreases were measured with enzyme-linked immunosorbent assay (ELISA). The expression of the autophagy-related protein LC3 was determined with Western Blot. The pathological changes in the pancreas were observed with microscopy., Results: (1) The survival time in the LPS + Wortmannin group was significantly shorter than that in the LPS group (hours: 7.50±0.64 vs. 11.90±0.13, χ (2) = 19.847, P = 0.001). There was no significant difference in the survival time between LPS + Mito Q and LPS groups (hours: 11.60±0.24 vs. 11.90±0.13, χ (2) = 1.055, P = 0.137). (2) The serum amylase in the LPS 6 hours, LPS + Wortmannin 4 hours, and LPS + Mito Q 6 hours groups were significantly higher than those in the control group at the same time points (U/L: 2 881.00±550.12 vs. 2 099.20±249.57, 3 672.00±779.24 vs. 2 081.36±245.18, 2 975.20±687.03 vs. 2 099.20±249.57, all P < 0.05), and were significantly lowered in LPS 12 hours group (U/L: 794.00±218.71 vs. 2 086.80±261.75, P < 0.01). The pancreatic ROS in the LPS 6 hours and 12 hours groups, LPS + Wortmannin 4 hours group, and LPS + Mito Q 6 hours group were significantly higher than those of the control group at the same time points (kU/L: 3.18±1.06 vs. 1.78±0.37, 3.63±1.08 vs. 1.85±0.41, 3.14±0.98 vs. 1.65±0.34, 3.17±1.03 vs. 1.78±0.37, all P < 0.05). The serum amylase and pancreatic ROS in LPS + Wortmannin 4 hours group were significantly higher than those of the LPS group at the same time points (U/L: 3 672.00±779.24 vs. 2 432.20±442.85, kU/L: 3.14±0.98 vs. 1.87±0.42, both P < 0.05), but there were no differences in above two parameters between LPS + Mito Q 6 hours group and LPS group (U/L: 2 975.20±687.03 vs. 2 881.00±550.12, kU/L: 3.17±1.03 vs. 3.18±1.06, both P > 0.05). Light microscopy showed that obvious pathological changes were found in the pancreas in the LPS 6 hours and 12 hours groups, LPS + Wortmannin 4 hours group, and LPS + Mito Q 6 hours group. Electron microscopy showed that the number of autophagic vacuoles increased 6 hours after LPS administration. There was no difference at any time point in the number of autophagic vacuoles between LPS + Mito Q 6 hours group and LPS 6 hours group, and the autophagic vacuoles were not found after Wortmannin intervention. It was demonstrated by Western Blot that the levels of LC3 protein in the LPS 6 hours and 12 hours groups, and LPS + Mito Q 6 hours group were significantly higher than those of the control group at the same time points (A value: 0.34±0.02 vs. 0.17±0.02, 0.37±0.03 vs. 0.18±0.04, 0.36±0.02 vs. 0.17±0.02, all P < 0.05), but there were no differences between LPS 12 hours group or LPS + Mito Q 6 hours group and LPS 6 hours group (both P > 0.05)., Conclusions: Autophagy prevents exocrine dysfunction of pancreas in septic rats, and the autophagic capacity or autophagosome-formation rate may determine the development of exocrine pancreatic dysfunction. The mitochondria-targeted antioxidant Mito Q does not prevent exocrine dysfunction of pancreas.

Objective: To study the effects of 21 kinds of traditional Chinese medicines on tyrosinase., Methods: The catalytic reactive velocity of tyrosinase was determined by vision spectrophotometry so as to evaluate the upregulation of traditional Chinese medicines extracts., Results: 21 time-curves of catalytic reaction of tyrosinase were obtained., Conclusion: 13 kinds of traditional Chinese medicines extracts in vitro showed a upregulation to tyrosinase activity (P < 0.01). Scutellaria baicalensis and Cremastra appendiculata showed a better upregulation to tyrosinase activity.

Objective: To compare enhanced spiral computed tomography (SCT), and plain CT with pathological findings in the diagnosis of peritoneal metastasis., Methods: Thirty-eight patients with peritoneal metastasis were examined by whole abdominal plain CT and enhanced SCT within one week before operation. The CT findings were compared with the pathological findings of specimens obtained during operation., Results: In the early phase of contrast SCT, various degrees of enhancement were observed in the majority of peritoneal metastases. Primary cancers and the metastatic lesions were enhanced to same degree. For lesions with rich blood supply, a 2 mm metastatic lesion was usually detected by contrast SCT. The sensitivity of plain CT and enhanced SCT for the detection of peritoneal metastasis in all involvements were 46.7% and 76.6% (chi(2) = 29.07, P < 0.005). For contrast SCT, the detection rates of peritoneal carcinomatosis were higher then 83% in the fallopian tubes, ovary, subphrenic spaces, mesentery of small intestine, transverse colon and omentum., Conclusion: Enhanced spiral CT, being superior to plain CT, is effective in detecting and diagnosing peritoneal metastasis.