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Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation

Nuclear Science and Techniques 2024年第2期35卷 183-209页

作者： Guo-Peng Yu yong-feng cheng Na Zhang Ping-Jian Ming Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China

The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle *** models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear *** analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic *** show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic *** the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to *** performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,*** performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited *** the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.

关键词： Supercritical CO_(2)Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods

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Effects of cooling rate on vermicular graphite percentage in a brake drum produced by onestep cored wire injection

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China Foundry 2015年第5期12卷 349-353页

作者： Yu-shuang feng Ze-sheng Ji He-sheng Wu yong-cheng feng School of Materials Science and Engineering Harbin University of Science and Technology Harbin Kedewei Metallurgy Co. Ltd. Shandong Ductile Iron Pipes Co. Ltd.

In this research, a vermicular graphite cast iron brake drum was produced by cored wire injection in a one-step method. Silica sand and low-density alumina-silicate ceramic were used as molding materials in order to investigate the effect of cooling rate on percentage of vermicular graphite and mechanical properties of the brake drum casting. Several thermocouples were inserted into the casting in the desired positions to measure the temperature change. By means of one-step cored wire injection, the two residual concentrations of Mg and RE were effectively controlled in the ranges of 0.013%-0.017% and 0.019%-0.025%, respectively, which are crucial for the production of vermicular graphite cast iron and the formation of vermicular graphite. In addition, the cooling rate had a significant effect on the vermicular graphite percentage. In the case of the silica mold brake drum casting, there was an obvious difference in the cooling rate with the wall change, leading to a change in vermicular graphite percentage from 70.8% to 90%. In the low-density alumina-silicate ceramic mold casting, no obvious change in temperature was detected by the thermocouples and the percentage of the vermicular graphite was stable at 85%. Therefore, the vermicular graphite cast iron brake drum with a better combination of mechanical properties could be obtained.

关键词： cored wire injection in one-step vermicular graphite cast iron cooling rate vermicular graphite percentage brake drum

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Prognostic factors for 5-year survival after local excision of rectal cancer

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World Journal of Gastroenterology 2009年第10期15卷 1242-1245页

作者： Dong-Bing Zhao yong-Kai Wu yong-Fu Shao cheng-feng Wang Jian-Qiang Cai Cancer Institute (Hospital) Chinese Academy of Medical Sciences and Peking UnionMedical College Beijing 100021 China

AIM:To evaluate the prognostic factors for 5-year survival after local excision of rectal cancer,and to examine the therapeutic efficacy and surgical indications for this procedure. METHODS:Clinical data,obtained from 106 local rectal cancer excisions performed between January 1980 and December 2005,were retrospectively *** analysis was performed using the Kaplan-Meier method,statistical comparisons were performed using the log-rank test,and multivariate analysis was performed using the Cox proportional hazards model. RESULTS:Transanal,transsacral,and transvaginal excisions were performed in 92,12,and 2 cases, *** rate of complication,local recurrence, and 5-year survival was 6.6%,17.0%,and 86.7%, *** analysis showed that T stage, vascular invasion,and local recurrence were related to the prognosis of the cases(P<0.05).Multivariate analysis showed that T stage[P=0.011,95% confidence interval(CI)=1.194-3.878]and local recurrence(P=0.022,95%CI=1.194-10.160)were the major prognostic factors for 5-year survival of cases after local excision of rectal cancer. CONCLUSION:Local rectal cancer excision is associated with few complications,and suitable for stages Tis and T1 rectal *** of local recurrence,active postoperative follow-up,and administration of salvage therapy are the effective methods to increase the efficacy of local excision of rectal cancer.

关键词： Rectal cancer Surgery Local excision Recurrence Prognosis

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Anorectal malignant melanomas: Retrospective experience with surgical management

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World Journal of Gastroenterology 2011年第4期17卷 534-539页

作者： Xu Che Dong-Bing Zhao yong-Kai Wu cheng-feng Wang Jian-Qiang Cai yong-Fu Shao Ping Zhao Department of Abdominal Surgical Oncology Cancer Hospital Chinese Academy of Medical Sciences and Peking Union MedicalCollege Beijing 100021 China

AIM: To present the experience and outcomes of the surgical treatment for the patients with anorectal melanoma from the Cancer Hospital, Chinese Academy of Medical Sciences. METHODS: Medical records of the diagnosis, surgery, and follow-up of 56 patients with anorectal melanoma who underwent surgery between 1975 and 2008 were retrospectively reviewed. The factors predictive for the survival rate of these patients were identified using multivariate analysis. RESULTS: The 5-year survival rate of the 56 patients with anorectal melanoma was 20%, 36 patients underwent abdominoperineal resection (APR) and 20 patients underwent wide local excision (WLE). The rates of local recurrence of the APR and WLE groups were 16.13% (5/36) and 68.75% (13/20), (P = 0.001), and the median survival time was 22 mo and 21 mo, respectively (P = 0.481). Univariate survival analysis demonstrated that the number of tumor and the depth of invasion had significant effects on the survival (P < 0.05). Multivariate analysis showed that the number of tumor [P = 0.017, 95% confidence interval (CI) = 1.273-11.075] and the depth of invasion (P = 0.015, 95% CI = 1.249-7.591) were independent prognostic factors influencing the survival rate. CONCLUSION: Complete or R0 resection is the first choice of treatment for anorectal melanoma, prognosis is poor regardless of surgical approach, and early diagnosis is the key to improved survival rate for patients with anorectal melanoma.

关键词： Anorectal melanomas Prognostic factors Surgical management Survival rate

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Comparative and optimized studies on radiosynthesis of O-(2-[^(18)F]fluoroethyl)-L-tyrosine

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Nuclear Science and Techniques 2005年第5期16卷 283-288页

作者： WANG Ming-Wei YIN Duan-Zhi WANG yong-Xian cheng Deng-feng LI Gu-Cai ZHOU Wei Radiopharmaceutical Centre Shanghai Institute of Applied Physics the Chinese Academy of Sciences Shanghai 201800

O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET), one of radiolabelled amino acids, is a very promising brain tumor positron emission tomography (PET) imaging agent and holds clinical potential. This paper described out a comparative and optimized radiosynthesis of [18F]FET, concerning three aspects of its two-step preparation method, including reaction components, heating methods and reaction models. As a result, good radiochemical yield (about 45%, no-decay-corrected) and radiochemical purity (more than 95%) were achieved, and total synthesis time of [18F]FET was shortened within 20 min and radiation exposure time also decreased.

关键词：酪氨酸放射合成衍生物氨基酸

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Elevation of vascular endothelial growth factor production and its effect on revascularization and function of graft islets in diabetic rats

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World Journal of Gastroenterology 2007年第20期13卷 2862-2866页

作者： Ying cheng yong-feng Liu Jia-Lin Zhang Tie-Min Li Ning Zhao Organ Transplant Unit of First Hospital of China Medical University Shenyang 110001 Liaoning Province China

AIM: To determine whether the elevated vascular endothelial growth factor (VEGF) expression produced by the transfected vascular endothelial cells (VECs) could stimulate angiogenesis of the graft islets and exert its effect on the graft function. METHODS: Thirty diabetic recipient rats were divided into three groups (n = 10 per group). In the control group,300 IEQ islets were transplanted in each rat under the capsule of the right kidney,which were considered as marginal grafts. In the VEC group,VEC together with the islets were transplanted in each rat. In the VEGF group,VEC transfected by pIRES2-EGFP/ VEGF165 plasmid and the islets were transplanted in each rat. Blood glucose and insulin levels were evaluated every other day after operation. Intravenous glucose tolerance test (IVGTT) was performed 10 d after the transplantation. Hematoxylin and eosin (HE) staining was used to evaluate the histological features of the graft islets. Immunohistochemical staining was used to detect insulin-6,VEGF and CD34 (MVD) expression in the graft islets. RESULTS: Blood glucose and insulin levels in the VEGF group restored to normal 3 d after transplantation. In contrast,diabetic rats receiving the same islets with or without normal VECs displayed moderate hyperglycemia and insulin,without a significant difference between these two groups. IVGTT showed that both the amplitude of blood glucose induction and the kinetics of blood glucose in the VEGF group restored to normal after transplantation. H&E and immunohistochemical staining showed the presence of a large amount of graft islets under the capsule of the kidney,which were positively stained with insulin-6 and VEGF antibodies in the VEGF group. In the cell masses,CD34-stained VECs were observed. The similar masses were also seen in the other two groups,but with a fewer positive cells stained with insulin-6 and CD34 antibodies. No VEGF-positive cells appeared in these groups. Microvessel density (MVD) was significantly higher in

关键词： Islet transplantation Revascularization, Vascular endothelial growth factor Gene transfer Vascular endothelial cells

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Oddi sphincter function after canine auto-pancreas transplantation with bladder drainage

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World Journal of Gastroenterology 2003年第12期9卷 2849-2852页

作者： Gui-Chen Li Chun-Hui Yuan Ying cheng yong-feng Liu Department of Surgery and Organ Transplant Unit,the First Affiliated Hospital,China Medical University,Shenyang 110001,Liaoning Province,China Department of Surgery and Organ Transplant Unit the First Affiliated Hospital China Medical University Shenyang 110001 Liaoning Province China. lgc763@***

AIM: Several neural and hormonal factors are known to affect motility of sphincter of Oddi (SO). The major roles of SO are to regulate the flow of bile and pancreatic juice into the duodenum and to prevent the reflux of duodenal contents into the biliary and pancreatic duct. After pancreas transplantation, graft SO was denervated and graft pancreatitis might have relations to SO motility. The motilityof SO after canine pancreas transplantation with bladder drainage was investigated. METHODS: Normal canine SO manometry and pancreas graft SO manometry after pancreas transplantation with bladder drainage were performed in seven dogs respectively before and after cholecystokinin (CCK) administration. Data of SO basal pressure, contraction frequency, amplitude and motility index after transplantation and CCK administration were compared with that in controls and before CCK ***: SO showed regular contractions with a certain basal pressure in control dogs. After transplantation, the graft SO basal pressure and contraction frequency were higher than that in controls, but the amplitude decreased (P＜0.01). There was no great difference in SO motility *** administration could relax normal SO but stimulate graft SO after pancreas transplantation with bladder *** CCK administration, SO basal pressure, frequency and motility index were increased significantly (P＜0.05), in comparison with that before administration. The amplitude remained unchanged (P＞0.05), in comparison with that before CCK ***: After auto-pancreas transplantation with bladder drainage, canine SO motility was inhibited. Basal pressure and frequency increased but amplitude *** administration after transplantation had an inhibitory effect on canine SO instead of a relaxation effect observed in normal canine SO. This will increase the resistance of SO to the pancreatic juice flow and induce pancreatic juice stagnation and can not prevent reflux of

关键词： Oddi括约肌自体胰腺移植膀胱导液术动物实验

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Design and realization of a magnetic-type absorber with a broadened operating frequency band

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Chinese Physics B 2013年第1期22卷 384-388页

作者：周永江庞永强程海峰 Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace and Materials Engineering National University of Defense Technology

In this paper, we present an efficient method to obtain absorbers with broadened operating frequency bands. They are accomplished by using conventional magnetic absorbing materials （MAMs） in the forms of array and mesh structures, which are similar to those in the case of a frequency selective surface. The proposed approach is verified not only by simulations but also by experimental results under the normal incidence at microwave frequencies. Moreover, the wideband absorber is lighter than the conventional magnetic absorber. These results indicate that our proposed absorbing structures can be used for designing good electromagnetic absorbers.

关键词： magnetic absorbing material periodic structure bandwidth

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沙漠地区风积沙地基输电线路装配式基础真型试验研究

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岩土力学 2012年第11期33卷 3230-3236页

作者：程永锋丁士君中国电力科学研究院输变电工程力学研究所北京100055

沙漠风积沙地基输电线路杆塔基础设计是当前我国电网建设中的关键研究课题之一。沙漠风积沙属于特殊土地基,这种地基上的输电线路装配式基础缺少相关设计依据。针对沙漠风积沙地基输电线路基础工程的特点,进行了输电线路装配式基础的真... 详细信息

沙漠风积沙地基输电线路杆塔基础设计是当前我国电网建设中的关键研究课题之一。沙漠风积沙属于特殊土地基,这种地基上的输电线路装配式基础缺少相关设计依据。针对沙漠风积沙地基输电线路基础工程的特点,进行了输电线路装配式基础的真型试验,得到了上拔与水平荷载、下压与水平荷载联合作用下的承载变形特性、基础构件的应变特性、基础底板与风积沙地基之间的接触压力变化规律。根据测试结果,确定了沙漠地区风积沙地基装配式基础的地基承载力和上拔角取值,得到了基础稳定的最不利工况,有助于提高基础设计的可靠性和合理性。试验结果为沙漠地区台远-塔中220 kV输电线路基础工程的设计提供了依据。

关键词：风积沙输电线路装配式基础真型试验垂直-水平组合荷载上拔角

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Comparison of antioxidant activities between salvianolic acid B and Ginkgo biloba extract(EGb 761)

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Acta Pharmacologica Sinica 2006年第9期27卷 1137-1145页

作者： Chang-suo LIU yong cheng Jin-feng HU Wei ZHANG Nai-hong CHEN Jun-tian ZHANG~2 Department of Neuropharmacology,Institute of Materia Medica,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100050.China Department of Neuropharmacology Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China

Aim:To investigate and compare the antioxidant activities of salvianolic acid B(SalB)and Ginkgo biloba extract(EGb 761)in aqueous solution,rat microsomesand the cellular ***:Superoxide anion(O2~-)was generated usingxanthine/xanthine oxidase system and phenazine methosulate/NADH system,andthe effects of SalB and EGb 761 on the generation of O2~- were achieved by spectro-photometric measurement of the product formed on reduction of nitro *** different methods were used to assess the scavenging effects ofthe extracts on hydroxyl radical(.OH):HPLC method was used for quantitation *** by oxy-radical trapping of 5,5-dimethyl- 1-pyrroline-N-oxide(DMPO)to formDMPO-OH adducts in Fe2+-*** confirm the HPLC data,.OHwas also measured by spectrophotometry using a commercial detection ***-lipid peroxidation effects of the extracts in microsomes of rat brain,liver andkidney induced by ascorbate-NADPH were determined by thiobarbituric acid(TBA)*** protective effects of the extracts on peroxide hydrogen(H2O2)-induced oxidative damage in SH-SY5Y cells were investigated by assessing cellviability assay,the level of lipid peroxidation,and the lactate dehydrogenase(LDH)***:Both SalB and EGb 761 were able to scavenge O2~- ***,inhibit lipid peroxidation of microsomes,and protect SH-SY5Y ceils againstH2O2-induced oxidative ***,the concentration of SalB was far lowerthan that of EGb 761 when a similar effect was ***:The antioxi-dant efficiency of SalB was greater than that of EGb *** results suggestthat SalB,like EGb 761,has promising potential in treating oxidative damage-derived neurodegenerative disorders.

关键词： antioxidant Ginkgo biloba extract 761 free radical salvianolic acid B SH-SY5Y cells

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