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A two dimensional coupled model of fluid flow and heat transfer of liquid steel and water in a mold was established to investigate the influence of inlet cooling water temperature and velocity on the mold tube temperature field and average mold heat flux.Solved by Fluent,this model simulated the flow and heat transfer of liquid steel and cooling water,solidified shell growth,and heat transfer across air gap and mold fluxes by conduction and radiation. The model's accuracy was verified by comparing the shell thickness and copper tube temperature field with other researches. Model results suggest that the inlet cooling water temperature notably affects the cold face temperature of the copper tube. If the inlet cooling water temperature exceeds 313 K,the highest temperature of the cold face will surpass the boiling point of water. However,an increase of 0.49 m·s-1 in water velocity can diminish the adverse effects of an increase of 4 K in inlet cooling water temperature.

Most of known attack signature generation systems took either black-box method or white-box method,both of which were limited in several aspects,such as costing a long time to capture sufficient samples,demanding arduous manual analysis and requiring source code of the vulnerable program.An attack signature generation method based on an innovative traceable dynamic taint analysis framework was proposed.By monitoring the vulnerable process execution,the executing trace and the constrain conditions exactly related to input data exploiting the vulnerability was extracted.Finally,by restoring the execution context and supplementing the determinant statements an executable Turing machine signature was attained.A prototype system was implemented and evaluated with different attack samples,which proved that the proposed method was able to generate accurate attack signature fast.

In a groundwater plant, removal of iron, manganese, and ammonia nitrogen was performed via a purification process using a filter column at a low temperature (5-6℃). Iron, manganese and ammonia [Fe(Ⅱ) 0-19.26 mg·L -1 , Mn(Ⅱ) 0.52-2.05 mg·L -1 , and NH 4 + -N 0.37-2.59 mg·L -1 ] were analyzed to explore the ammonia nitrogen removal efficiency under different iron and manganese concentrations. The results showed that when the concentration of manganese in the inlet water was maintained at approximately 0.6 mg·L -1 and the concentration of ferrous iron in the inlet water was increased, with the increase of iron oxides in the filter layer, the ratio of ammonia nitrogen removed by adsorption of iron oxides increased, while the ratio of ammonia nitrogen removed by nitrification will decreased and adsorption preceded nitrification. When the concentration of ferrous iron in the water was maintained at approximately 8 mg·L -1 and 11 mg·L -1 , and the concentration of manganese in the water was increased, the proportion of ammonia nitrogen removed by adsorption did not increase with the increase of manganese oxide, and the removal route of ammonia nitrogen hardly changed. This is because less manganese oxides were formed 20 cm before the filter layer, which had little effect on the ammonia nitrogen adsorbed in this range. The production area of manganese oxides was concentrated below 20 cm of the filter layer, and most ammonia nitrogen was removed by adsorption and nitrification before this area, and the manganese oxides in this area did not adsorb ammonia nitrogen.

In a groundwater plant we carried out a process operation test of biological removal of iron and manganese nitrification coupled with completely autotrophic ammonium removal over nitrite (CANON) (Fe(Ⅱ) 2.91-6.35 mg·L -1 , Mn(Ⅱ) 0.47-0.98 mg·L -1 , NH 4 + -N 1.15-2.26 mg·L -1 ) at low temperature (6-8℃), to explore the effects of filter speed and water quality on ammonia nitrogen removal. The results showed that the mature low-temperature biological filter column, which had been out of service for one month, was cultured for 40 days at a filtration rate of 2 m·h -1 and successfully started. In this process, when the water inlet concentration remained the same, the improved filter speed would reduce the efficiency of ammonia nitrogen capture by the filter column, increase the concentration of ammonia nitrogen in the depth of the filter layer, and improve the efficiency of ammonia nitrogen ions capture by anaerobic ammonia oxidation bacteria (AnAOB) in the depth of the filter layer, so that the ammonia nitrogen removed by CANON in the water increased, while the ammonia nitrogen removed by nitrification decreased. When the filter speed remained unchanged, the concentration of ammonia nitrogen in water was increased to make the ammonia nitrogen with higher concentration enter the filter layer, which increased the concentration of ammonia nitrogen in the zone where ammonia nitrogen and nitrous nitrogen coexist, and improved the net catching efficiency of AnAOB on ammonia nitrogen ions in the filter layer, thus resulting in an increase in ammonia nitrogen removed by CANON.

Mature biological phosphorus removal granules were inoculated into a SBR. The effect of the ammonia concentration on biological phosphorus removal granules system was investigated by increasing the concentration of ammonia in the influent. The ability of the system to withstand ammonia loading was determined. The results showed that when the influent ammonia concentration was below 45 mg·L -1 , the biological phosphorus removal granule system showed good performance. The TP removal efficiency was above 96%, the COD removal efficiency was over 89%. The effluent TP concentration and COD concentration were 0.4 mg·L -1 and 25 mg·L -1 respectively. The particle size was above 950 μm and the SVI was below 45 mL·g -1 . When the influent ammonia concentration was 60 mg·L -1 , the removal efficiency of TP was more than 95%. The effluent TP concentration was below 0.5 mg·L -1 , the particle size was 760 μm, and the SVI was 56 mL·g -1 . Furthermore, the biological phosphorus removal granules partially disintegrated and the metabolism and growth of PAOs began to be inhibited in the system. When the influent ammonia concentration reached 70 mg·L -1 , the removal efficiency of TP was 70%, the effluent TP concentration was about 3 mg·L -1 , the particle size was 570 μm, the SVI was 75 mL·g -1 , and the value of PN/PS was about 7.50. The biological phosphorus granules severely disintegrated and the metabolism and growth of PAOs was severely inhibited in the system. Moreover, as the influent ammonia concentration increased, the protein increased and polysaccharide decreased from the microbial secretion of biological phosphorus removal granules. Moreover, the value of PN/PS increased, the biological phosphorus removal granules disintegrated, the particle size decreased, the SVI increased, and the structure and function of the biological phosphorus removal granules were destroyed.

In this study, the effect of COD loading on a biological phosphorus removal granule system under different phosphorus concentrations was investigated by changing the concentration of total phosphorus (TP) and COD in the influent. The lowest concentration of COD for good performance of the biological phosphorus removal system under different phosphorus concentrations was obtained. The results show that when the concentration of TP was 10 mg·L -1 in the influent, the lowest concentration of COD for good performance of the biological phosphorus removal system was 175 mg·L -1 . The concentration of TP in the effluent was below 0.5 mg·L -1 ; the particle size and SVI were 1020 μm and 36 mL·g -1 , respectively; and the contents of PN and PS (by MLSS) were 78 mg·g -1 and 39 mg·g -1 , respectively. Furthermore, the PN/PS was lower and the granules had good structure and performance. When the concentration of TP was 6 mg·L -1 in the influent, the lowest concentration of COD for good performance of the biological phosphorus removal system was 150 mg·L -1 . The concentration of TP in the effluent was below 0.3 mg·L -1 ; the particle size and SVI were respectively 960 μm and 35 mL·g -1 ; and the contents of PN and PS were 75 mg·g -1 and 35 mg·g -1 , respectively. Moreover, the PN/PS was lower and the granules had good structure and performance. The removal efficiency of COD was above 83% and the concentration of COD in the effluent was below 25 mg·L -1 throughout the operational process. Under different the influent phosphorus concentrations, the contents of PN and PS decreased, PN/PS increased, particle size decreased, SVI increased, and the structure and performance of the biological phosphorus removal granules deteriorated as the COD concentration decreased.

Objective: To study the clinicopathologic features of inflammatory pseudotumor-like follicular dendritic cell tumor of spleen., Methods: One case of inflammatory pseudotumor-like follicular dendritic cell tumor of spleen was examined macroscopically and microscopically. Immunohistochemical study for CD21, CD23, CD35, clusterin, S-100 protein, vimentin, smooth muscle actin, CD1a, CD68, ALK protein, CD30, CD31, CD34, CD3 and CD20 was performed on formalin-fixed, paraffin-embedded sections by standard EnVision method. In-situ hybridization for Epstein-Barr virus (EBV)-encoded RNA was also carried out., Results: Macroscopically, inflammatory pseudotumor-like follicular dendritic cell tumor was large in size, tan-colored, soft to rubbery in consistance and associated with central hemorrhage and necrosis. Histological examination showed scattered follicular dendritic cells admixed with abundant lymphocytes and plasma cells in the background, simulating inflammatory pseudotumor. On high-power magnification, the follicular dendritic cells possessed a moderate amount of pale to lightly eosinophilic cytoplasm, with indistinct cell borders. The nuclei were ovoid or spindly, with vesicular or stippled chromatin and small distinct, often centrally located, nucleoli. Some of the tumor cells showed nuclear pleomorphism and contained irregular foldings of nuclear membrane, coarse chromatin and prominent eosinophilic nucleoli. Mitotic figures were rarely identified. Immunohistochemical study showed that the tumor cells were positive for vimentin, clusterin, smooth muscle actin and CD68. They were weakly and focally positive for CD35 and S-100 protein, but negative for CD21, CD23, CD1a, ALK protein, CD30, CD31 and CD34. Most of the background lymphocytes were of T-lineage (CD3-positive) ,some were CD20 (B-cell marker)-positive. EBV RNA was demonstrated in the tumor cells by in-situ hybridization analysis., Conclusions: Inflammatory pseudotumor-like follicular dendritic cell tumor is a rarely encountered low-grade malignancy with distinctive morphologic pattern. It is associated with EBV infection.

Objective: To study the clinicopathologic features and differential diagnosis of atypical teratoid/rhabdoid tumor (AT/RT) occurring in the central nervous system., Methods: Two cases of AT/RT were studied by hematoxylin-eosin, reticulin and immunohistochemical staining. The clinical and pathologic features were analyzed and the literatures reviewed., Results: Histologically, AT/RT was characterized by the presence of rhabdoid cells associated with various degrees of primitive neuroectodermal, epithelial or mesenchymal differentiation. Abundant reticulin fibers and a complex immunophenotype were observed. The tumor cells were positive for vimentin, CD99, epithelial membrane antigen, cytokeratin, glial fibrillary acidic protein, S-100 protein, neurofilament, desmin and smooth muscle actin. They were negative for synaptophysin, MyoD1, placental alkaline phosphatase and HMB45., Conclusions: AT/RT is a highly malignant tumor occurring in the central nervous system. It manifests mainly in children and occasionally in adults. The tumor is characterized by a heterogeneous histologic and immunohistochemical phenotype. It needs to be distinguished from a number of central nervous system tumors, including medulloblastoma, primitive neuroectodermal tumor, germ cell neoplasm and rhabdoid meningioma.

Objective: To investigate the inhibitory role of esophageal cancer related gene 2 (ECRG2) on proliferation of human esophageal cancer cell EC9706., Methods: Recombinant plasmid pcDNA3.1-ECRG2 with ECRG2 open reading frame was constructed. The cells were transfected with either pcDNA3.1 or pcDNA3.1-ECRG2 using Lipofectamin 2000. The expression of ECRG2 protein was examined by Dot Blot analysis. The effects of ECRG2 on cell proliferation and malignant was analyzed by colony formation assay. The variation of P53 and P21 were detected in EC9706 cells with or without expression of ECRG2., Results: The plasmid of pcDNA3.1-ECRG2 was successfully established. Colony formation activity of EC9706/pcDNA3.1-ECRG2 was 18% while that of the control cell was 55% in six well plate (P < 0.05). The activity of anchorage-independent proliferation of EC9706/pcDNA3.1-ECRG2 was lower than that of EC9706/pcDNA3.1 in soft agar. After transfected with pcDNA3.1-ECRG2, the expression of P53 and P21 were higher than control., Conclusion: ECRG2 can reduced the abilities of proliferation and of anchorage-independent proliferation of EC9706 cells which is through p53 pathway possibility.