[en] The thermodynamic analysis and the coupling and optimization between chemical synthesis and power generation in a polygeneration system are presented. Unlike full conversion of syngas into chemicals in the traditional SNG (synthetic natural gas) production system, by moderate conversion the sharp increase in energy consumption for SNG synthesis can be avoided in the new system. Also, by recovering the chemical unconverted gas for combined cycle, electricity is cogenerated efficiently. Results show that the overall efficiency of the novel system can be as high as 59%–65%. And compared to single production systems, the (energy saving ratio) ESR of the new system is over 11.0% and the energy consumption for SNG production can be decreased by around 12%. Sensitivity analysis shows that an optimized conversion ratio of SNG, (chemicals to power output ratio) CPOR, recycle ratio of the unconverted gas Ru, and pressure ratio of gas turbine can lead to the maximum of ESR. Abolishing the syngas composition adjustment and improving the inlet temperature of gas turbine both can help to enhance the system efficiency. Under low Ru, improving the H₂/CO mole ratio in the syngas helps to improve system efficiency, while under high Ru, an optimized H₂/CO can lead to the maximum of ESR. - Highlights: • Present a coal based cogeneration system for SNG and power using unconverted gas. • The overall system efficiency is 59%–65%, and the energy saving ratio is over 11%. • An optimized SNG conversion ratio, chemicals to power ratio yield best performance. • At low recycle ratios, higher H₂/CO ratio in syngas improves system efficiency. • At high recycle ratios, an optimized H₂/CO leads to maximum of system efficiency

[en] Highlights: • Present exergy analysis to three types of complicated polygeneration systems. • Compare the energy efficiencies of different chemical and power cogeneration plants. • System performance is optimized and energy saving mechanism is presented. • Effects of key parameters on exergy losses and system performance is investigated. • Main sources of exergy losses: coal gasification, SNG methanation, fuel combustion. - Abstract: The energy saving mechanism and the potential of efficiency improvement for coal to synthetic/substitute natural gas and power plant with different schemes and CO₂ capture is disclosed through exergy analysis, and the effects of key parameters on exergy losses and system performance are investigated. Scheme A represents the system without CO₂ capture but with a full syngas component adjustment and partial recycle of the chemical unconverted gas, Scheme B represents the system without CO₂ capture and syngas component adjustment but with partial recycle of the chemical unconverted gas, and Scheme C represents the SNG and power cogeneration with CO₂ capture and partial recycle of the chemical unconverted gas but without syngas component adjustment. Results show that the exergy efficiencies of Scheme A, B and C range from 56% to 62%, 57% to 67%, 52% to 62%, respectively. Coal gasification, water–gas-shift process, SNG methanation, and fuel combustion in combined cycle are identified as the main sources of exergy losses. Compared with Scheme A, the exergy efficiency of Scheme B is higher due to the avoidance of exergy losses from syngas adjustment. Scheme C is less energy efficient than Scheme B because of the CO₂ capture. Compared with single product systems, the total exergy input of Scheme A, B and C can be reduced by 7.0–11.0%, 14.0–19.0%, 15.0–21.0%, respectively assuming the same product output. The chemical to power output ratio (CPOR) will impact the exergy losses of the whole plant greatly. For all schemes, with the increasing CPOR, the exergy losses for chemical synthesis island will increase whereas the exergy losses for power island will decrease. Especially high CPOR will cause sharp exergy losses of chemical synthesis island. The coupling between exergy losses for chemical synthesis and power islands leads to an optimal CPOR making the total exergy losses of the plant minimal and the system efficiency maximized. The results presented in this paper can help to confirm the potential of system integration and can be a guide for system integration

[en] Highlights: • Present techno-economic analysis of SNG and power cogeneration from coal. • Predict cost reduction potential for SNG and power cogeneration. • Current localization level of key technologies in China is investigated. • Investigate role of efficiency upgrade and further localization in cost reduction. - Abstract: The cogeneration of substitute/synthetic natural gas (SNG) and power from coal based plants with CO₂ capture is an effective way to improve energy efficiency and to reduce CO₂ emissions. In this paper, we evaluate the techno-economic performance of a SNG and power cogeneration technology with CO₂ capture. Current localization level (the cost difference of a technology in different nations and districts) of each subunit of this technology is analyzed. The cost reduction potential of this technology is also predicted, and the role of technology localization and efficiency upgrade in cost reduction is investigated based on a range of learning rates and different coal prices from 90$/t to 150$/t. Results show that the unit investment of this cogeneration technology presented in our previous paper is around 1700$/kW currently and the investment of SNG synthesis, coal gasification and combined cycle unit comprises over 60% of the total investment. The equivalent SNG production cost is quite sensitive to coal prices and ranges from 0.15 to 0.50$/Nm³. Through localization, the unit investment of this technology can be decreased by 30% currently. The key technologies including coal gasification, SNG synthesis and high performance gas turbine need further localization because of their relatively low current localization levels and big localization potential. Through cost learning, the future investment of the technology can be decreased to 700–1100$/kW, which may be competitive with the unit investment of IGCC technology with CO₂ capture and even may be lower than that of the pulverized coal power plant with CO₂ capture. Technology localization and efficiency upgrade will play important roles in cost reduction, which can contribute 300–500$/kW and 125–225$/kW to cost reduction, respectively. The results presented in this paper indicate that the coal to SNG and power technology with CO₂ capture is a promising and competitive option for energy saving and CO₂ abatement, and can be a support for policy making, technology options etc

[en] This article mainly introduces the development of a gamma spectrometer, which monitors the radioactivity in the seawater, aiming at monitoring extreme low activity and concentration of radioactive nuclide in the seawater. In the development, FPGA technology is applied to realize the low energy consumption and digitalization of gamma spectrometer that has the functions of weak pulse signal processing, digital acquisition and pileup rejection. Test results show that the digital gamma spectrometer has the ability of the quantitative analysis and measurement for the radioactive nuclide in the seawater and this ability meets the design requirements. (authors)

[en] Cathepsin D (CD) is a lysosomal acid proteinase that is related to malignant progression, invasion, and a poor prognosis in several tumors. The aim of this study was to evaluate the prognostic clinical significance of CD and p53 expression in pretreatment biopsy specimens from patients with locally advanced rectal cancer who were treated with preoperative chemoradiation. Eighty-nine patients with locally advanced rectal cancer (cT3/T4 or N+) were included in this study. Preoperative chemoradiation consisted of a dose of 50.4 Gy of pelvic radiation and two concurrent cycles of administration of 5-fluorouracil and leucovorin. Surgery was performed six weeks after chemoradiation. CD and p53 expression in pretreatment formalin-fixed paraffin-embedded tumor biopsy specimens were assessed by immunohistochemical staining using a CD and p53 monoclonal antibodies. The threshold value for a positive stain in tumor tissue and stromal cells was 1+ intensity in 10% of the tumors or stromal cells, respectively. Positive CD expression was found in 57 (64%) of the tumors and 32 (35%) of the stromal cell specimens. There was no association with CD expression of the tumor or stromal cells and patient characteristics. There was a correlation between tumor CD expression with stromal cell CD expression (p=0.01). Overexpression of p53 was not a significant prognostic factor. The 5-year overall survival (OS) and disease-free survival (DFS) rates were not different between tumor CD-negative and positive patient biopsy samples (69% vs. 65%, 60% vs. 61%, respectively). The 5-year OS rates in the tumor-negative/stromal cell-negative, tumor-negative/stromal cell-positive, tumor-positive/stromal cell-negative and tumor-positive/ stromal cell-positive biopsy samples were 75%, 28%, 62%, and 73%, respectively. Stromal cell staining only without positive tumor staining demonstrated the worst overall survival prognosis for patients (p=0.013). Overexpression of p53 in rectal biopsy tissue was not associated with prognostic significance. In the pretreatment biopsy specimens, an exclusive increase in CD expression in stromal cells without tumor expression was related to poor overall survival in patients with locally advanced rectal cancer treated with preoperative chemoradiation

[en] In recent years, the experimental results about the ratio of the branching ratios R${}_{D^{(\ast <!--\; ???\; -->)}}$ and R${}_{K^{(\ast <!--\; ???\; -->)}}$, which are in the semileptonic b → cl → ${\stackrel{¯<!--\; ??\; -->}{\mathrm{\nu <!--\; ??\; -->}}}_l$ and b → sl${}^{+}$l${}^{-<!--\; ???\; -->}$ decays, have been observed to deviate from the Standard Model prediction by 1.4σ, 2.5σ, 2.4σ and 2.2σ respectively. Motivated by these anomalies and by the abundant B${}^{\ast <!--\; ???\; -->}$ data samples, we investigate possible New Physics effects of the vector leptoquark in the semileptonic decay ${\stackrel{¯<!--\; ??\; -->}{B}}_{u,d,s,c}^{\ast <!--\; ???\; -->}$ → Vτ${}^{-<!--\; ???\; -->}$${\stackrel{¯<!--\; ??\; -->}{\mathrm{\nu <!--\; ??\; -->}}}_{\mathrm{\tau <!--\; ??\; -->}}$ (V=D${}_{u,d,s}^{\ast <!--\; ???\; -->}$, J//psi). which is induced by b → cτ${}^{-<!--\; ???\; -->}$${\stackrel{¯<!--\; ??\; -->}{\mathrm{\nu <!--\; ??\; -->}}}_{\mathrm{\tau <!--\; ??\; -->}}$ at the quark level. Using the best fit solutions for the new operator Wilson coefficients and the relevant form factors which are obtained in the light-front quark model, we find that (i) the contributions of the vector leptoquark to dΓ${}^{(L)}$/dq${}^2$(${\stackrel{¯<!--\; ??\; -->}{B}}_{u,d,s,c}^{\ast <!--\; ???\; -->}$ → Vτ${}^{-<!--\; ???\; -->}$${\stackrel{¯<!--\; ??\; -->}{\mathrm{\nu <!--\; ??\; -->}}}_{\mathrm{\tau <!--\; ??\; -->}}$ and $R_V^{\ast <!--\; ???\; -->(L)}(q^2)$ to be significant; (ii) the two best fit solutions in the vector leptoquark are indistinguishable from each other and give similar amounts of enhancements to these two observables; (iii) both two cases of the vector leptoquark give nearly same results as those of the Standard Model for A${}_{FB}^{\mathrm{\tau <!--\; ??\; -->}}$(q${}^2$) , P${}_{\mathrm{\tau <!--\; ??\; -->}}$(q${}^2$) and F${}_L^{\ast <!--\; ???\; -->V}$(q${}^2$). We hope that the numerical results in this work will be tested in the future high energy experiments.

[en] Objective: To evaluate the diagnostic accuracy of coronary in-stent restenosis using 64- slice multislice computed tomography (MSCT) coronary angiography. Methods: Fifty nine patients after stent implantation with 112 coronary stents were examined with 64-section MSCT. Scanning was undertaken by electrocardiographically gated, but an automatic bolus-tracking method. For image reconstruction, an edgeenhancing kernel (B46f)was applied. All segments within stent were assessed by two observers in consensus, and were graded according to the following scheme: patient stent, in-stent intimal hyperplasia (lumen reduction <50%), in-stent restenosis ( =>50%). Consensus reading was compared with those of coronary angiography. Results: 109 stented lesions (97.3%) were classified as evaluable in MSCT. Overall, 10 of 12 in-stent restenosis were correctly detected by MSCT. Sensitivity, specificity, positive predictive value, and negative predictive value were 83.3%, 99%, 90.9%, and 97.3%, respectively. Conclusion: 64-MSCT has high diagnostic accuracy for detecting in-stent restenosis, indicating and suggesting as a useful tool for the follow up after coronary stenting. (authors)

[en] LiPb loop is the indispensable facility to investigate key issues for liquid LiPb blanket of fusion reactors, and its distribution of temperature and velocity fields of liquid LiPb is very necessary for the analysis of experiment results. DRAGON-I is the first thermal convection LiPb loop of China, the temperature and velocity fields of liquid LiPb was simulated with 2D and 3D models by FLUENT code. The results show that the temperature of liquid LiPb changes in conformity with design demands, with less change on the section of pipe diameter direction, and there was almost no fluctuation for velocity inside the pipe except for small regions at the two right-angle corners at the top of the loop, the velocity is averaged about 0.14 m/s. (authors)

[en] Objective: To discuss the endovascular covered stenting for the treatment of renal pseudoaneurysms due to a variety of causes. Methods: During the period from August 2008 to September 2012, six patients with renal pseudoaneurysm caused by renal artery injury or renal transplantation were admitted to the hospital. As the patients were not suitable for conventional embolization therapy, endovascular implantation of covered stent was carried out. The cause of pseudoaneurysm included trauma (n = 1), iatrogenic injury (n = 1) and renal transplantation (n = 4). During stent implantation procedure, anti-platelet aggregation medication was given, and after the procedure anticoagulation therapy was used for 3 days, and oral administration of plavix and aspirin was conducted for half a year, which was followed by continuous oral administration of aspirin. Results: In 2 patients the bleeding stopped after the endovascular implantation of covered stent and the renal blood perfusion was well maintained, and in the remaining four patients the pseudoaneurysm was completely isolated. During the following-up period lasting 2-34 months (mean 19 months), loss of renal function was seen in two patients, who had suffered from pseudoaneurysm at transplanted renal artery anastomotic stoma and had received covered stent implantation of internal iliac artery. One patient developed infection of unknown cause, and removal of transplanted kidney had to be performed. Excellent results were achieved in the remaining patients. No recurrence of symptoms, fistula or artery stenosis occurred. Conclusion: For renal pseudoaneurysm patients who are not suitable for conventional renal artery embolization therapy, endovascular implantation of covered stent may after all be accepted as an effective and proper treatment although its long-term efficacy needs to be further evaluated. (authors)

[en] Objective: To discuss the influence of different methods of using antibiotic prophylaxis on the occurrence of liver abscess occurring after transcatheter arterial chemoembolization (TACE). Methods: Between January 2010 and August 2012, a total of 869 TACE procedures were performed in 560 patients with hepatic malignant tumor in authors' department. The clinical data were retrospectively analyzed. Before Jan. 1, 2012, a total of 543 TACE procedures were carried out, which was classified as group A. Patients in group A received prophylactic antibiotics before as well as after TACE. After Jan. 1, 2012, a total of 326 TACE procedures were performed, which was regarded as group B. Patients in group B received preoperative prophylactic antibiotics only. The incidence of postoperative liver abscess of the two groups was recorded, and the difference in the occurrence of liver abscess between the two groups was statistically analyzed by using χ² test. Results: The overall occurrence of liver abscess in 869 TACE procedures was 1.15% (10/869). The incidences of liver abscess of group A and group B were 0.73% (4/543) and 1.84% (6/326) respectively. The difference between the two groups was not significant (P = 0.2507). Of the 10 patients developing liver abscess after TACE, 9 had a history of surgery, PTCD or radiofrequency ablation procedure before TACE. Conclusion: The results of his study indicate that the prophylactic using methods of antibiotics do not affect the occurrence of liver abscess occurring after TACE. The mechanism of liver abscess occurring after TACE is very complex. Therefore, an aggressive use of antibiotics in patients with high risk of liver abscess after TACE requires serious consideration. (authors)