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A thermophilic Geobacillus strain DM-2 from a deep-subsurface oil reservoir was investigated on its capability of degrading crude oil under various conditions as well as its characters on degrading hydrocarbons in optimal conditions. The results showed that Geobacillus strain DM-2 was able to degrade crude oil under anoxic wide-range conditions with pH ranging from 4.0 to 10.0, high temperature in the range of 45-70 degrees C and saline concentration ranging from 0.2% to 3.0%. Furthermore, the optimal temperature and pH value for utilizing hydrocarbons by the strain were 60 degrees C and 7.0, respectively. Under such optimal conditions, the strain utilized liquid paraffine emulsified by itself as its carbon source for growth; further analysis by gas chromatography (GC) and infrared absorption spectroscopy demonstrated that it was able to degrade n-alkanes (C14-C30), branched-chain alkanes and aromatic hydrocarbons in crude oil and could also utilize long-chain n-alkanes from C16 to C36, among of which the degradation efficiency of C28 was the highest, up to 88.95%. One metabolite of the strain oxidizing alkanes is fatty acid.While utilizing C16 as carbon source for 5 d, only one fatty acid-acetic acid was detected by HPLC and MS as the product, with the amount of 0.312 g/L, which indicated that it degraded n-alkanes with pathway of inferior terminal oxidation,and then followed by a beta-oxidation pathway. Due to its characters of efficient emulsification, high-performance degradation of hydrocarbons and fatty-acid production under high temperature and anoxic condition, the strain DM-2 may be potentially applied to oil-waste treatment and microbial enhanced heavy oil recovery in extreme conditions.

Gordonia sp. C-6 can desulfurize benzothiophene (BT) as the pathway similar to the "4S" pathway of dibenzothiophene (DBT)-desulfurizing, but the strain can not grow with DBT as the sole sulfur source. At current, there were not related reports on BT-desulfurizing genes at home or abroad. The DBT-desulfurizing genes of Rhodocossus erythropolis DS-3, dszA, dszB, dszC and dszABC were introduced into Gordonia sp. C-6 respectively using a Rhodococcus-E. coli shuttle vector, to construct new recombinant strains Gordonia sp. CRA, Gordonia sp. CRB, Gordonia sp. CRC and Gordonia sp. CRABC, the enzyme activities of which was respectively 76.8 micromol x (g x h)(-1), 51.6 micromol x (g x h)(-1) and 62.4 micromol x (g x h)(-1), increasing by 1.5 times compared with 35.2 micromol x (g x h)(-1), 21.3 micromol x (g x h)(-1) and 25.5 micromol x (g x h)(-1) of wild strain Rhodocossus erythropolis DS-3. Of the recombinant strains, only recombinant strains Gordonia sp. CRC with DszC and Gordonia sp. CRABC with DszABC exhibite significant growth with DBT as the sole sulfur source, Gordonia sp. CRA with DszA and Gordonia sp. CRB with DszB could not live with DBT as the sole sulfur source. The results show that, DBT monoxygenase and BT monoxygenase, catalyzed the first two steps of DBT and BT oxidation, respectively, are the key enzymes responsible for substrate-recognition, however, the enzymes catalyzed the last two steps have the similar substrate specificity. The active sites of the two monoxygenase could be predicted by comparing with the sequence differences of their amino acids.

It is a brand-new method to isolate functional bacteria from high temperature petroleum reservoirs according to the sequence information obtained from PCR-DGGE patterns. Three-set primers of 16S rDNA high variable region, V3, V8, V9, were compared. The results showed that more microbial diversity information could be obtained from the PCR product of V9 region. Sequence analysis indicated that the dominant bacteria in the petroleum reservoir had high sequence similarity with bacteria from alpha, beta, gamma-Proteobacterias and Bacilli from the GenBank database. According to the sequences information, multi-cultivation technology including enrichment cultivation, special cultivation and direct cultivation methods were employed, and finally, five strains (three strains by traditional methods) were isolated from oil-water samples. Among them, three thermophilic hydrocarbon-degrading bacteria, which belonged to Bacillus sp., Geobacillus sp. and Petrobacter sp., respectively, could grow well under 55 degrees C in obligate anaerobic condition. The crude oil could be utilized by these strains with the degradation rate of 56.5%, 70.01% and 31.78% respectively along with the viscosity reduction rate of 40%, 54.55% and 29.09%, meanwhile the solidify points of crude oil were reduced by 3.7, 5.2 and 3.1 degrees C. Therefore, the combination of sequence information from PCR-DGGE and altering cultivation conditions is an available novel method to isolate more functional microorganisms which could be utilized for microbial enhanced oil recovery.

Holographic recording with orthogonally polarized beams in a cesium-doped KNSBN [(K0.5Na0.5)0.2(Sr0.75Ba0.25)0.9Nb2O6] crystal has been studied. It was found that this kind of photorefractive crystal possesses high linear dichroism, which makes it suitable for use in polarization holography. The diffraction efficiency as a function of the polarization orientation of the reference beam and as a function of the fringe modulation at the optimum polarization orientation of the reference beam is experimentally investigated. Theoretical fitting based on Kahmann models was performed and agrees well with the experimental data. In the experiments, both polarization holography and conventional holography are used to record a binary object. The reconstruction shows that polarization holography with Ce:KNSBN is highly effective, exhibiting high diffraction efficiency and reduced fanning noise.

Substituted benzothiophenes (BTs) and dibenzothiophenes (DBTs) remain in diesel oil following conventional desulfurization by hydrodesulfurization. A mixture of washed cells (13.6 g dry cell wt l(-1)) of Rhodococcus erythropolis DS-3 and Gordonia sp. C-6 were employed to desulfurize hydrodesulfurized diesel oil; its sulfur content was reduced from 1.26 g l(-1) to 180 mg l(-1), approx 86% (w/w) of the total sulfur was removed from diesel oil after three cycles of biodesulfurization. The average desulfurization rate was 0.22 mg sulfur (g dry cell wt)(-1) h(-1). A bacterial mixture is therefore efficient for the practical biodesulfurization of diesel oil.

An artificial immune system (ARTIS) enlightened by the biological immune system is emerging as a new field of computation intelligence research. At present, it showed us many properties after the research to the immune system, including distributed computation, self-organization and lightweight, which were discovered to meet the requests of ARTIS. So the Immunology applied to the intrusion detection will be a brand-new area. This paper, firstly introduces the development of intrusion detection technology, it discusses the Immunity-based technical research to detect network intrusions, then it analyzes the problems exited in the Immunity-based technical to detect network intrusions, lastly summarize the works of my group and expects the research emphasis and development trend in the future.

Dibenzothiophene (DBT) and its derivatives can be microbially desulfurized by enzymes DszC, DszA, and DszB, which are encoded by the operon dszABC and contribute to the conversion in tandem. We investigated the expression characteristics of the dsz operon. Our results revealed that the levels of transcription and translation of dszA , dszB , and dszC decreased according to the positions of the genes in the dsz operon. Furthermore, the translation of dszB was repressed by an overlapping structure in the dsz operon. In order to get better and steady expression of the Dsz enzymes and optimize the metabolic flux of DBT, we rearranged the dsz operon according to the catalytic capabilities of the Dsz enzymes and expressed the rearranged dsz operon, dszBCA , in Rhodococcus erythropolis . After rearrangement, the ratio of dszA , dszB , and dszC mRNAs in the cells was changed, from 11:3.3:1 to 1:16:5. Western blot analysis revealed that the levels of expression of dszB and dszC had been enhanced but that the expression of dszA had decreased. The desulfurization activity of resting cells prepared from R. erythropolis DRB, which carried the rearranged dsz operon, was about 12-fold higher than that of resting cells of R. erythropolis DRA, which carried the original operon in a similarly constructed vector.

A low-temperature hydrocarbon-degrading strain T7-2 was isolated from sea-mud of Bohai polluted area and identified as Rhodococcus erythropolis, which could use diesel oil as carbon source. The optimal temperature and pH for the strain utilizing ethanol was 15 degrees C and 7.8, and the optimal concentration of ethanol and the seed culture was 0.5% and 10(8) CFU/mL, respectively. Inoculated to artificial seawater which was added (NH4)2SO5 2.64 g/L, Na2HPO4 2.5 g/L and yeast extract 0.015 g/L after 7 days of culture at the temperature of 15 degrees C, the rate of degradation was 73.2%. The strain could degrade a large range of n-alkane from C12 to C36.

The amount of organic nitrides contained in fuel oil is smaller than the one of organic sulfur compounds, but the existence of them is enough to affect the invariability of oil product greatly , and has a big effect on the color of oil. They also contribute to catalyst poisoning during the refining of crude oil, thus reducing the catalyzing rate of the catalyst and increasing process costs. Further more, some nitrogen organic compounds possess mutagenic and toxic activities. The combustion of these contaminants form nitrogen oxides (NOx), releasing of which to the air will cause the formation of acid rain and hence to air pollution. The classical hydroprocessing methods of nitrogen removal are costly and complicated, so the scientists are more and more interested in microbial denitrogenation. The aspects as follows are introduced, including the aromatic nitrogen compounds of fuel oil, the varieties of denitrogenation techincs, the classes of microbial denitrogenation and its biochemical pathways, molecular genetics developments of carbazole-degradative genes, and our opinion of the research direction in the future.

A benzothiophene-desulfurizing strain was isolated and identified as Gordonia sp. C-6, which could degrade benzothiophene (BT) in a way analogous to the 4S pathway. It was found strain C-6 had the ability to grow in KT-BT medium whose sole source of sulfur was BT or its derivatives, whereas it couldn't grow well in a medium with DBT and its derivatives as the sole source of sulfur, the desulfurized product was identified as 2-(2'-hydroxyphenyl) ethan-1-al or its isomer benzofuran by GC-MS analysis. Desulfurization activity of strain C-6 was investigated. About 0.15mmol/L(50%) BT was desulfurized by strain C-6 after it was incubated in KT-BT medium at 30 degrees C for 48h, the residual BT has volatilized during aerobic fermentation. The quantitative detection of the benzothiophene-desulfurizing products was established with o-hydroxyphenylacetic acid as standard compound, the standard curve was fitted by Matlab.

Rhodococcus sp. PR-1 with high capability of demulsification on a surfactant-stabilized kerosene-water model emulsion was isolated from sewage of Dagang oil field. It could demulsify the model emulsion completely in 8 hours at 55 degrees C and had better demulsifying capability than chemical demulsifier DGF-01. The freezing-thawing and autoclaving had no effect on the process of demulsification, yet ultrasonic disposal and deal with organic solvent could inhibit its activity. A linear relationship, not the first order reaction that was used in some references, was observed between the percentage of demulsification and reaction time. The demulsifying capability of PR-1 was mainly resulted from the hydrophobic surfaces of microbial cells, which were characterized by the mycolic acids with the carbon-chain-length from 27 to 54. These results provide foundation for biological application on demulsifying crude oil emulsions in produced water of oil field.

A strain Fds-1, which can specially break the C-S bond of dibenzothiophene (DBT) and convert DBT into 2-hydrobenzophene (2-HBP), was screened out from soil soaked with crude oil and identified as Bacillus subtilis. Both Gibb's reaction and GC-MS analysis proved that this bacterium could remove sulfur of DBT by "4S" pathway. The optimal temperature of desulfurization is 30 degrees C. At this temperature, Fds-1 could remove 0.5mmol/L organ sulfur of DBT in 72h, so it is suitable to decrease the sulfur content of diesel oil. The final product named 2-HBP is a water-soluble compound. This research focused on the desulfurization methods of diesel oil using Fds-1 resting cells. The results showed Fds-1 exhibited strong degradation capacity of DBT and alkyl-DBT in diesel oil. Experiments of two diesel oil samples for desulfurization proved that Fds-1 did not break the carbon-carbon backbone and the calorific value of diesel oil was reserved. Therefore strain Fds-1 is significant to deep biodesulfurisation comparing the hydro-desulfurization of diesel oil.

Rhodococcus sp. FS-1 ,which can specially break the C[single bond]S bond of dibenzothiophene (DBT) and convert DBT into 2-hydrobenzophene by "4S" pathway, is used to decrease the sulfur content in diesel oil. This research focuses on the diesel oil desulfurization using resting cells of Rhodococcus sp. FS-1. The research result indicate that the desulfurization activity of the resting cells of Rhodococcus sp. FS-1 was strongly high. When the concentration of DBT was 0.5 - 1.0mmol/L and the ratio of oil/water was 1:5, the effect of desulfurization was highest. The desulfurization rate was over 85 % when desulfurizing the diesel oil twice. GC analysis proves that this process did not break the carbon-carbon backbone. The calorific value of diesel oil is reserved.

In this paper, the quality improvement of Laser Microprobe Emission Spectral Analysis (LMESA) lines in argon atmosphere at reduced pressure was experimentally investigated. The experimental setup consists of a YGJ-II laser micro-spectral analyzer and a photo-electro detection system. The temporal behavior and the intensity distribution of Cu I 324.7 nm and Cu I 327.4 nm lines of the copper alloy standard samples were studied. The results show that LMESA spectrum strongly depends on the environment gas, its pressure and the auxiliary excitation parameters. When the diameter at the end of graphite auxiliary electrodes is 1.5 mm, the distance between the electrodes is 4 mm, the center of the electrodes is 3 mm above the sample surface, the voltage of the auxiliary excitation is 1,300 V and the argon pressure is 33.2 Kpa, the emission time of Cu I 324.7 nm and Cu I 327.4 nm is about 500 microseconds longer than that in the air. The emission intensity of Cu I 324.7 nm and Cu I 327.4 nm is about 4 times higher than that in the air at the same pressure and is about 2 times higher than that in the air at normal pressure. The full width at half maximum of the spectral lines is obviously narrowed.

In this research, we experimentally studied the spectral quality of the CUl324.7nm and Cul327.4nm lines of the copper alloy standard samples in argon atmosphere at reduced pressure by a laser microprobe emission spectral analysis (LMESA) system. Compared with the results obtained in air atmosphere with the pressure of 760Torr, the spectral quality of the lines obtained obvious improvement. As the distance between the two graphite electrodes is 4mm and the pressure is 250Torr, the intensity of the spectral lines is about 2-3 times of that in the air atmosphere and the Full-Width-at-Half-Maximum (FWHM) is nearly one third of that in the air atmosphere.