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Coupled Heat Transfer Simulation of the Spiral Water Wall in a Double Reheat Ultra-supercritical Boiler

Journal of Thermal Science 2018年第6期27卷 592-601页

作者： DONG Jiancong ZHOU tuo WU Xiaojiang zhang Jian FAN Haojie zhang Zhongxiao School of Mechanical Engineering Shanghai Jiao Tong University Institute of Engineering Thermophysics Chinese Academy of Sciences Department of Research and Development Shanghai Boiler Works Co. Ltd.

This paper presented a coupled heat transfer model combining the combustion in the furnace and the ultra-supercritical(USC) heat transfer in the water wall tubes. The thermal analysis of the spiral water wall in a 1000 MW double reheat USC boiler was conducted by the coupled heat transfer simulations. The simulation results show that there are two peak heat flux regions on each wall of spiral water wall, where the primary combustion zone and burnt-out zone locate respectively. In the full load condition, the maximal heat flux of the primary combustion zone is close to 500 kW/m^2, which is higher than that in the conventional single reheat USC boilers. The heat flux along the furnace width presents a parabolic shape that the values in the furnace center are much higher than that in the corner regions. The distribution of water wall temperature has a perfect accordance with the heat flux distribution of the parabolic shape curves, which can illustrate the distribution of water wall temperature is mainly determined by heat flux on the water wall. The maximal water wall temperature occurs at the middle width of furnace wall and approaches 530°C, which can be allowed by the metal material of water wall tube 12Cr1MoVG. In the primary combustion zone, the wall temperatures in half load are almost close to the values in 75% load condition, caused by the heat transfer deterioration of the subcritical pressure fluid under the high heat flux condition. The simulation results in this study are beneficial to the better design and operational optimization for the double reheat USC boilers.

关键词： coupled model heat transfer spiral water wall double reheat ultra-supercritical

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纤维桩联合不同冠部修复方式修复穿髓型非龋性颈部缺损牙体的力学分析

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中国组织工程研究 2025年第4期29卷 866-871页

作者：陈倚珑张旭李红首都医科大学附属北京口腔医院北京市100050 北京市房山区良乡医院北京市102401

背景:使用纤维桩修复穿髓型非龋性颈部缺损可以改变牙齿的应力分布,显著降低患牙折裂风险,但关于纤维桩改善牙体抗折性的力学机制及穿髓型非龋性颈部缺损的最佳冠部修复方式尚有争论。目的:综述纤维桩修复穿髓型非龋性颈部缺损后的应力... 详细信息

背景:使用纤维桩修复穿髓型非龋性颈部缺损可以改变牙齿的应力分布,显著降低患牙折裂风险,但关于纤维桩改善牙体抗折性的力学机制及穿髓型非龋性颈部缺损的最佳冠部修复方式尚有争论。目的:综述纤维桩修复穿髓型非龋性颈部缺损后的应力分布模式,在各种受力状态下的抗折能力与断裂模式,以及纤维桩联合不同冠部修复方式的最新研究进展。方法:应用计算机在PubMed和中国知网数据库中检索2008年9月至2023年9月发表的相关文献,英文检索词为“non-carious cervical lesions,endodontically treated teeth restoration,endodontically treated teeth stress distribution”,中文检索词为“非龋性颈部缺损,根管治疗后牙体修复,根管治疗后牙齿应力分布”,最终纳入56篇文献进行分析。结果与结论:穿髓型非龋性颈部缺损根管治疗后,应用纤维桩修复可部分改善牙齿颈部应力,同时不会增加牙根纵裂的风险;使应力分布更加均匀,提高牙齿的抗折性。使用纤维桩修复的非龋性颈部缺损牙齿若折断,其断裂模式显示出有利的、可恢复的或可修复的断裂模式。纤维桩联合瓷贴面或贴面式嵌体可能会成为修复穿髓型非龋性颈部缺损的一种较理想微创修复方法。

关键词：非龋性颈部缺损穿髓型三维有限元分析纤维桩冠部修复应力分布抗折性折断模式

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Correlation between microRNA-21 and expression of Th17 and Treg cells in microenvironment of rats with hepatocellular carcinoma

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Asian Pacific Journal of Tropical Medicine 2015年第9期8卷 747-750页

作者： Shao-Xin Yao Gui-Song zhang hong-Xia Cao Guang Song Zang-tuo Li Wei-Tao zhang Department of Interventional Therapy Affiliated Tangshan Workers Hospital of Hebei Medical University Department of Interventional Therapy Luanxian People's Hospital

Objective: To study the correlation between mi R-21 and Treg/Th17 ratio in the microenvironment of rats with hepatocellular carcinoma. Methods: Diethylnitrosamine was used to build the hepatocel ular carcinoma model of rats; the content of Treg cells and Th17 cells and the expression of mi R-21 in the peripheral blood of rats with hepatocellular carcinoma were detected. The statistical analysis was performed on the correlation between mi R-21 expression and Treg/Th17 ratio. Results: Hepatocellular carcinoma model of rats was successfully constructed. The proportion of Th17 cells among all CD4+T cells in the peripheral blood of rats with hepatocellular carcinoma was 5.319%, which was higher than the control group; while the proportion of Treg cells was 9.472%, which was higher than the control group. Treg/Th17 ratio in the model group was 1.781, compared with 1.478 in the control group. The expression of mi R-21 was increased in the peripheral blood of rats with hepatocellular carcinoma and it showed a positive correlation with the ratio of Treg/Th17. Conclusions: There is a positive correlation between the expression level of miR-21 and the ratio of Treg/Th17.

关键词： Hepatocellular carcinoma Th17 Cells Treg Cells miR-21 Correlation analysis

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PVT系统解的正则性

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应用数学 2025年第1期38卷 256-262页

作者：向鑫懿张森祥罗宏四川师范大学数学科学学院四川成都610066

物质的气、液、固三态转换是常见的自然现象,常用Physical Vapor Transport(PVT)系统进行描述.本文主要研究PVT系统动力学方程组初边值问题解的存在性及正则性.首先,引入具有变分结构的算子,证明算子的弱连续性,并结合泛函估计证明PVT... 详细信息

物质的气、液、固三态转换是常见的自然现象,常用Physical Vapor Transport(PVT)系统进行描述.本文主要研究PVT系统动力学方程组初边值问题解的存在性及正则性.首先,引入具有变分结构的算子,证明算子的弱连续性,并结合泛函估计证明PVT系统解的存在性;其次,利用能量估计和Gronwall不等式证明PVT系统解的唯一性;最后,通过ADN理论提高了PVT系统解的正则性.

关键词： PVT系统存在性唯一性正则性

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Performances of different efficiency calibration methods of high-purity-germanium gamma-ray spectrometry in an inter-comparison exercise

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Nuclear Science and Techniques 2019年第3期30卷 9-14页

作者： Bao-Lu Yang Qiang Zhou Jing zhang Shuai-Mo Yao Ze-Shu Li Wen-hong Li Fei tuo Key Laboratory of Radiological Protection and Nuclear Emergency National Institute for Radiological ProtectionChinese Center for Disease Control and Prevention

This study reports the performances of efficiency calibrations for high-purity-germanium gamma-ray spectrometry using the source-, Laboratory Sourceless Object Calibration Software(LabSOCS)-and ANGLE-based methods in an inter-comparison exercise. Although the results of LabSOCS and ANGLE for ^(241)Am emitting lowenergy gamma rays were not very satisfactory, all of the three efficiency calibration methods passed acceptance criteria. The results confirmed the reliability of the calculation codes ANGLE and LabSOCS as alternative efficiency calibration methods in high-purity-germanium gamma spectrometry. This study is likely to promote the further application of the ANGLE and LabSOCS calculation codes in radioactivity measurements.

关键词： Efficiency calibration ANGLE Laboratory Sourceless Object Calibration Software (LabSOCS) Gamma-ray spectrometry

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Modelling the iron ore price index:A new perspective from a hybrid data reconstructed EEMD-GORU model

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Journal of Management Science and Engineering 2020年第3期5卷 212-225页

作者： Jingjing tuo Fan zhang International Business School Shaanxi Normal UniversityXi'an710061China

As iron ore is the fundamental steel production resource,predicting its price is strategically important for risk management at related enterprises and *** on a signal decomposition technology and an artificial neural network,this paper proposes a hybrid EEMD-GORU model and a novel data reconstruction method to explore the price risk and fluctuation correlations between China's iron ore futures and spot markets,and to forecast the price index series of China's and international iron ore spot markets from the futures *** analysis found that the iron ore futures market in China better reflected the price fluctuations and risk factors in the imported and international iron ore spot ***,the forward price in China's iron ore futures market was unable to adequately reflect the changes in the domestic iron ore market,and was therefore unable to fully disseminate domestic iron ore market *** proposed model was found to provide better market risk perceptions and predictions through its combinations of the different volatility information in futures and spot *** results are valuable ref-erences for the early-warning and management of the related enterprise project risks.

关键词： Iron ore market Neural networks Price forecasting Project risk management Series decomposition

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Effect of yttrium addition on microstructure, mechanical and corrosion properties of 20Cr13 martensitic stainless steel

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Journal of Iron and Steel Research International 2020年第4期27卷 451-460页

作者： Qi-yu Zang Yang-fan Jin tuo zhang Yi-tao Yang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

The effects of rare-earth yttrium(Y)element on the microstructure,mechanical properties and corrosion properties of 20Cr13 martensitic stainless steel were investigated by optical microscopy,scanning electron microscopy and tensile *** experiments were carried out to study the effect of rare-earth element Y addition on corrosion *** results showed that the addition of 0.02 wt.%rare-earth yttrium to martensitic stainless steel could affect the microstructure transformation,and Ac3 temperature was obviously *** the stainless steel after heat treatment,there were more pro-eutectoid ferrite in the steel with 0.02 wt.%*** mechanical test results showed that the addition of 0.02 wt.%yttrium could significantly improve the tensile strength and elongation of the steel,which was related to the influence of yttrium element on inclusions in the test *** the quenching temperature of 0.02 wt.%yttrium steel increasing,the content of the ferrite in steel was affected and the corrosion resistance was remarkably improved.

关键词： Yttrium Martensitic stainless steel Mechanical property Microstructural characterization Corrosion

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TGFBI and CHST6 gene analysis in Chinese stromal corneal dystrophies

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International Journal of Ophthalmology(English edition) 2012年第3期5卷 301-306页

作者： Yin Li tuo Li Xiu-Sheng Song Jia-zhang Li Qing-Song Wu and hong-Yan Li Department of Ophthalmology Central Hospital of Enshi Autonomous Prefecture Enshi Autonomous Prefecture 445000 Hubei Province China

AIM:To investigate whether mutations in TGFBI gene or CHST6 gene correlated with stromal corneal dystrophies(CD) in 8 Chinese probands.· METHODS:Eight unrelated patients with stromal corneal dystrophies were recruited in this study;all affected members were assessed by completely ophthalmologic *** DNA was extracted from peripheral leukocytes,17 exons of TGFBI gene and the exon of CHST6 gene were amplified by polymerase chain reaction(PCR),sequenced directly and compared with the reference database.· RESULTS:Three heterozygous mutations in TGFBI gene were identified in six patients:c.370C>T(***124Cys) was found in exon 4 of TGFBI gene in three members,c.371G>A(***124His) was found in one patient;c.1663C>T(***555Trp) was found in exon 12 in other two *** addition,four polymorphisms with the nucleotide changes rs1442,rs1054124,rs4669,and rs35151677 were found in TGFBI *** were not identified in the rest of 2 affected individuals in TGFBI gene or CHST6 gene.· CONCLUSION:Within these patients,R124C,R124H and R555W mutations were co-segregated with the disease phenotypes and were specific mutations for lattice corneal dystrophy type I(LCD I),Avellino corneal dystrophy(ACD,GCDⅡ),granular corneal dystrophy type I(GCD I),*** study highlights the prevalence of codon 124 and codon 555 mutations in the TGFBI gene among the Chinese stromal corneal dystrophies patients.·

关键词： corneal dystrophies Mutation screening TGFBI gene TGFBI protein carbohydrate sulfotransferse CHST6

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Comparison of dental pulp periodontal therapy and conventional simple periodontal therapy as treatment modalities for severe periodontitis

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World Journal of Clinical Cases 2021年第33期9卷 10098-10105页

作者： Lu Li hong-Jie Chen Yi Lian tuo Wang Department of Stomatology The Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Department of Stomatology Wuhou District People's Hospital of ChengduChengdu 610041Sichuan ProvinceChina Department of Stomatology Chengdu Children Special HospitalChengdu 610041Sichuan ProvinceChina

BACKGROUND Severe periodontitis is a major oral health concern today as it can lead to loss of *** periodontal therapy has numerous pitfalls as it does not address the pulp-periodontal complex in its *** To investigate the effect of dental pulp periodontal therapy on the levels of interleukin-1β(IL-1β)and IL-10 in gingival crevicular fluid(GCF)in patients with severe *** Eighty-six patients with severe periodontitis were randomly divided into a research group(n=43)and a control group(n=43).The control group was treated with simple periodontal therapy,and the research group was treated with dental pulp periodontal *** total effective rates of the treatments;periodontal status before and after treatment through the measurement of the periodontal pocket probing depth(PPD),gingival sulcus bleeding index(SBI),mobility(MD),and plaque index(PLI);the levels of inflammatory factors IL-1βand IL-10 in the GCF;and the incidence of complications were calculated for both groups and compared using the Student’s t test and theχ^(2) *** The total effective rate of treatment in the study group(93.02%)was higher than that in the control group(76.74%;P<0.05).While before treatment,there was no significant difference in the PLI,MD,SBI,or PPD between the two groups,the post-treatment values of PLI,MD,SBI,and PPD(4.71±0.16 mm,0.61±0.09 mm,0.96±0.17 mm,and 0.76±0.26 mm,respectively)were significantly lower(P<0.05)in the research group than in the control group(5.35±0.24 mm,0.93±0.15 mm,1.35±0.30 mm,and 1.04±0.41 mm,respectively).There was no significant difference in the level of IL-1βor IL-10 in the GCF before treatment between the two groups;after treatment,the IL-1βlevel in the research group(139.04±15.54 pg/mL)was significantly lower than that in the control group(156.35±18.10 pg/mL),and the level of IL-10 in the research group(7.98±1.01 ug/L)was higher than that in the control group(5.56±0.96 ug/L)(P<0.05).The incidence of com

关键词： Severe periodontitis Dental pulp and periodontal therapy Interleukin-1β Interleukin-10

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Discovery of Balmer broad absorption lines in the quasar LBQS 1206+1052

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Research in Astronomy and Astrophysics 2012年第4期12卷 369-382页

作者： tuo Ji Ting-Gui Wang hong-Yan Zhou Hui-Yuan Wang Key Laboratory for Research in Galaxies and Cosmology University of Science and Technology of China （USTC） Hefei 230026 China Center for Astrophysics USTC Hefei 230026 China Polar Research Institute of China Shanghai 200136 China

We report the discovery of Balmer broad absorption lines （BALs） in the quasar LBQS 1206＋1052 and present a detailed analysis of the peculiar absorption line spectrum. Besides the Mg II λλ2796, 2803 doublet, BALs are also detected in the He I＊ multiplet at λλ2946, 3189, 3889 A arising from the metastable helium 2 3 S level, and in Hα and Hβ from the excited hydrogen H I＊ n = 2 level, which are rarely seen in quasar spectra. We identify two components in the BAL troughs of v ～ 2000 km s 1 width： One component shows an identical profile in H I＊, He I＊ and Mg II with its centroid blueshifted by v c ≈ 726 km s-1 . The other component is detected in He I＊ and Mg II with v c ≈ 1412 km s-1 . We estimate the column densities of H I＊, He I＊, and Mg II, and compare them with possible level population mechanisms. Our results favor the scenario that the Balmer BALs originate in a partially ionized region with a column density of N H ～ 10 21 10 22 cm-2 for an electron density of n e ～ 10 6 10 8 cm-3 via Lyα resonant scattering pumping. The harsh conditions needed may help to explain the rarity of Balmer absorption line systems in quasar spectra. With an i-band PSF magnitude of 16.50, LBQS 1206＋1052 is the brightest Balmer-BAL quasar ever reported. Its high brightness and unique spectral properties make LBQS 1206＋1052 a promising candidate for followup high-resolution spectroscopy, multi-band observations, and long-term monitoring.

关键词： galaxies active -- quasar absorption lines -- quasar individual (LBQS1206+1052)

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