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The purpose of this study was to examine the carbapenemase-encoding resistance genes and analyze homologous of multidrug-resistant Acinetobacter baumannii (MRAB) isolates from nosocomial infections. Seventy-six A. baumannii strains were collected from inpatients and object surface of devices in intensive care units from May 2008 to February 2011. Antibiotic susceptibility testing of 18 antimicrobial agents was performed. The presence of carbapenemase-encoding resistance genes was investigated by polymerase chain reaction. Genotyping and dendrogram analysis of A. baumannii strains from nosocomial infections were performed using the DiversiLab System. All of the 76 clinical A. baumannii isolates were shown multidrug resistance. The bla(OXA-23) gene was identified in the 76 MRAB strains, while bla(OXA-24), bla(OXA-58), VIM, IMP-1, IMP-4, SIM, and blaNDM-1 were absent in all. Twenty-four A. baumannii strains from the samples with nosocomial infections were classified into four unrelated groups and nine patterns. In conclusion, production of bla(OXA-23) in MRAB is one of the molecular mechanisms responsible for carbapenem resistance. The MRAB strains from unrelated groups show different drug resistance, but the homologous strains also have different drug resistance. Homologous analysis can provide scientific evidence for evaluation of epidemic status of nosocomial infection caused by MRAB.

Pb-Sn-Al (PSA) laminated composite electrode materials were prepared by means of vacuum hot pressing (VHP), through introducing a medium Sn for solving the immiscibility of Pb and Al. Compared to traditional Pb-(1.0%)Ag alloy electrode, zinc eletrodeposition experiments showed that the cell voltage was reduced by at least 120 mv, the polarization potential of electrode was decreased by 13.2%, the current efficiency was higher 1.3% and the surface morphology of cathode zinc was better and smoother as well as zinc crystals smaller and more dense, while the experiment of the resistance test also showed that the resistance was reduced by at least 50%, therefore, Pb-Sn-Al (PSA) laminated composite electrode materials have lower cell voltage, as well as excellent conductivity, which would have good prospect in development and application in zinc hydrometallurgical industry in the future.

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The overall effect of the application of established training system is very good, and the disqualification rate of the major departments decrease to various degrees.

In the process of recycling chemical product in coking object, ammonia and tar were indispensable both metallurgy and agriculture, so the control of separation process for tar-ammonia was one of the most important control problems. Due to the density difference between the tar and ammonia was greater, easier to separate, the control method based on PID was used in field at present. But the control effect of traditional PID was not good because of environment change and fluctuation in material composition. Separation process for tar-ammonia was analyzed firstly, in view of the shortcoming of traditional PID control algorithm, single neuron PID control algorithm based on variable scale method was adopted through using optimization method. Detailed algorithm steps were designed and applied to tar-ammonia separation system. Simulation results show that by comparison with traditional PID algorithm, the algorithm have the following advantages: faster learning speed, shorter adjusted time and good convergence performance.