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Improvement on application of Dancoff factor and resonance interference table

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Nuclear Science and Techniques 2016年第2期27卷 122-130页

作者： Yu Han Xiao-Feng Jiang de-zhong wang School of Nuclear Science and Engineering Shanghai Jiaotong University Shanghai 200240 China Shanghai NuStar Nuclear Power Technology Co. Ltd.Shanghai 200000 China

An improvement for application of Dancoff factor is developed. It combines Stamm'ler's two-term method for resonance integral calculation with neutron current method for Dancoff factor calculation. Stamm'ler's formulation, which is originally derived for the infinite lattice geometry, can be easily revised to contain the Dancoff factor explicitly, while the neutron current method can easily calculate the Dancoff factor for general irregular assembly geometry. For the resonance interference effects the resonance interference factor table is built in pairs of nuclides, only for the interference between 238 U and other resonance nuclides, spanning over a range of background cross-section and number density ratio of the pairing nuclides. A series of verification calculations have been carried out for problems of infinite lattice and single assembly geometry, with two or multiple resonance absorbers. For these verification calculations, our improvement on Dancoff factor application and resonance interference give good results.

关键词：共振干涉因子和应用积分计算几何形状干涉效应中子流核素

Direct numerical simulation of the viscoelastic channel flow using Giesekus model with variable parameters

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Journal of Hydrodynamics 2019年第2期31卷 326-332页

作者： Wei-guo Gu Yu Li de-zhong wang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The paper presents a direct numerical simulation(DNS)for the drag-reducing channel flow using the Giesekus model with variable *** is assumed that the relaxation time in the constitutive equation is varied depending on the local shear *** maximal drag reduction rate is obtained when variable parameters are applied in the Giesekus model at a high Weissenberg *** Reynolds shear stress is reduced when the Weissenberg number *** this case,the turbulence generation and transportation are further weakened and increasingly approach to the values in the experiments.

关键词： Viscoelastic fluid Giesekus model direct numerical simulation(DNS) Variable parameters

Numerical study on rotordynamic coefficients of the seal of molten salt pump

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Nuclear Science and Techniques 2016年第5期27卷 168-178页

作者： Yao-Yu Hu de-zhong wang Yuan Fu Jun-Lian Yin School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Institute of Applied Physics Shanghai 201800China

Molten salt pump is applied to pump high-temperature molten salt as the primary coolant of a molten salt *** pump,generally a vertical rotor system,suffers from radial force generated by the liquid seal component,and the rotordynamic characteristics of the pump are affected *** this paper,the rotordynamic coefficients of the tooth-on-stator liquid seal in molten salt pump are *** flow in the seal region is simulated using computational fluid dynamics *** of the inlet loss and the pre-swirl at the inlet region of the seal are *** coefficients of resistance and the wall parameters are obtained from the simulation results by data fitting *** rotordynamic coefficients are analyzed based on the bulk-flow model of liquid *** rotordynamic characteristics,with and without the liquid seal,of the objective molten salt pump are *** first critical speed of the rotor is found to *** analysis shows that the pump,being sensitive to unbalance force though,can operate safely under its design specifications.

关键词：动力特性系数泵密封熔盐泵数值研究转子动力特性转子系统整体流动液体密封

A novel method for gamma spectrum analysis of low-level and intermediate-level radioactive waste

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Nuclear Science and Techniques 2023年第6期34卷 199-213页

作者： Hui Yang Xin-Yu Zhang Wei-Guo Gu Bing Dong Xue-Zhi Jiang Wen-Tao Zhou de-zhong wang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai200240China

The uncertainty of nuclide libraries in the analysis of the gamma spectra of low-and intermediate-level radioactive waste(LILW)using existing methods produces unstable *** address this problem,a novel spectral analysis method is proposed in this *** this method,overlapping peaks are located using a continuous wavelet *** improved quadratic convolution method is proposed to calculate the widths of the peaks and establish a fourth-order filter model to estimate the Compton edge baseline with the overlapping *** with the adaptive sensitive nonlinear iterative peak,this method can effectively subtracts the ***,a function describing the peak shape as a filter is used to deconvolve the energy spectrum to achieve accurate qualitative and quantitative analyses of the nuclide without the aid of a nuclide *** spectrum acquisition experiments for standard point sources of Cs-137 and Eu-152,a segmented gamma scanning experiment for a 200 L standard drum,and a Monte Carlo simulation experiment for triple overlapping peaks using the closest energy of three typical LILW nuclides(Sb-125,Sb-124,and Cs-134)are *** results of the experiments indicate that(1)the novel method and gamma vision(GV)with an accurate nuclide library have the same spectral analysis capability,and the peak area calculation error is less than 4%;(2)compared with the GV,the analysis results of the novel method are more stable;(3)the novel method can be applied to the activity measurement of LILW,and the error of the activity reconstruction at the equivalent radius is 2.4%;and(4)The proposed novel method can quantitatively analyze all nuclides in LILW without a nuclide *** novel method can improve the accuracy and precision of LILW measurements,provide key technical support for the reasonable disposal of LILW,and ensure the safety of humans and the environment.

关键词： HPGe detector Low-level and intermediate-level radioactive waste Gamma spectrum analysis method deconvolution method Continuous wavelet transform

Large eddy simulation of unsteady flow in gas-liquid separator applied in thorium molten salt reactor

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Nuclear Science and Techniques 2018年第5期29卷 10-18页

作者： Jing-Jing Li Ya-Lan Qian Jun-Lian Yin Hua Li Wei Liu de-zhong wang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Applied Physics Shanghai 201800China

Axial gas-liquid separators have been adopted in fission gas removal systems for the development of thorium molten salt reactors. In our previous study, we observed an unsteady flow phenomenon in which the flow pattern is directly dependent on the backpressure in a gas-liquid separator; however, the underlying flow mechanism is still unknown. In order to move a step further in clarifying how the flow pattern evolves with a variation in backpressure, a large eddy simulation(LES) was adopted to study the flow field evolution. In the simulation, an artificial boundary was applied at the separator outlet under the assumption that the backpressure increases linearly. The numerical results indicate that the unsteady flow feature is captured by the LES approach, and the flow transition is mainly due to the axial velocity profile redistribution induced by the backpressure variation. With the increase in backpressure,the axial velocity near the downstream orifice transits from negative to positive. This change in the axial velocity sign forces the unstable spiral vortex to become a stable rectilinear vortex.

关键词： Swirl flow Thorium molten salt reactor Computational fluid dynamics Large eddy simulation

Promising xenograft animal model recapitulating the features of human pancreatic cancer

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World Journal of Gastroenterology 2020年第32期26卷 4802-4816页

作者： Jin-Xin Miao Jian-Yao wang Hao-Ze Li Hao-Ran Guo Louisa S Chard Dunmall zhong-Xian Zhang Zhen-Guo Cheng Dong-Ling Gao Jian-Zeng Dong zhong-de wang Yao-He wang Sino-British Research Centre for Molecular Oncology National Centre for International Research in Cell and Gene TherapyAcademy of Medical SciencesZhengzhou UniversityZhengzhou 450000Henan ProvinceChina Academy of Chinese Medical Sciences Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina Centre for Biomarkers and Biotherapeutics Barts Cancer InstituteQueen Mary University of LondonLondon EC1M6BQUnited Kingdom department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China department of Animal Dairy and Veterinary SciencesUtah State UniversityLogan UT 84341United States

BACKGROUND Multiple sites of metastasis and desmoplastic reactions in the stroma are key features of human pancreatic cancer(PC).There are currently no simple and reliable animal models that can mimic these features for accurate disease *** To create a new xenograft animal model that can faithfully recapitulate the features of human *** Interleukin 2 receptor subunit gamma(IL2RG)gene knockout Syrian hamster was created and characterized.A panel of human PC cell lines were transplanted into IL2RG knockout Syrian hamsters and severe immune-deficient mice subcutaneously or *** growth,local invasion,remote organ metastasis,histopathology,and molecular alterations of tumor cells and stroma were compared over *** The Syrian hamster with IL2RG gene knockout(named ZZU001)demonstrated an immune-deficient phenotype and ***001 hamsters faithfully recapitulated most features of human PC,in particular,they developed metastasis at multiple *** tissues derived from ZZU001 hamsters displayed desmoplastic reactions in the stroma and epithelial to mesenchymal transition phenotypes,whereas PC tissues derived from immune-deficient mice did not present such *** ZZU001 hamsters engrafted with human PC cells are a superior animal model compared to immune-deficient ***001 hamsters can be a valuable animal model for better understanding the molecular mechanism of tumorigenesis and metastasis and the evaluation of new drugs targeting human PC.

关键词： Pancreatic cancer Xenotrans plantation Syrian hamster IL-2 receptor gamma chain gene Metastasis Animal model

Comprehensive analysis of long non-coding RNA and mRNA expression profile in rectal cancer

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Chinese Medical Journal 2020年第11期133卷 1312-1321页

作者： de-zhong wang Guan-Yang Chen Yi-Feng Li Neng-Wei Zhang department of Gastroenterology Liver and Gallbladder SurgeryPeking University Ninth School of Clinical MedicineBeijing 100038China The Clinical Center of Gene and Cell Engineering Beijing Shijitan HospitalPeking University Ninth School of Clinical MedicineBeijing 100038China department of General Surgery Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

Background::Rectal cancer(RC)is a malignant tumor that seriously threatens human *** non-coding RNAs(lncRNAs)play a vital role in tumor ***,their exact expression features and functions remain obscure,and therefore was the aim of the current ***::We utilized the Affymetrix human GeneChip to screen differentially expressed profiles of lncRNAs and mRNAs from the cancer tissues and matched paracancer tissues of 6 RC *** Ontology(GO)and pathway enrichment analyses identified crucial functions and pathways of the aberrantly expressed *** used quantitative real-time polymerase chain reaction to verify the significant expression differences of 11 candidate lncRNAs between the cancer and paracancer ***-mRNA coexpression networks were built by calculating the Pearson correlation value to identify significant correlation *** bioinformatics tools GEPIA2,ONCOMINE,and PROGgeneV2 were used to mine the expression and prognosis of three crucial mRNAs and six verified *** endogenous RNA networks were constructed by predicting microRNA response elements and calculating free ***::We found 1658 differentially expressed lncRNAs(778 up-regulated and 880 down-regulated)and 1783 aberrantly expressed mRNAs(909 up-regulated and 874 down-regulated).GO and pathway enrichment analyses revealed the vital functions of the differentially expressed mRNAs,including cell proliferation,cell migration,angiogenesis,and cellular response to zinc *** canonical signaling pathways mainly included the interleukin-17,cell cycle,Wnt,and mineral absorption signaling *** lncRNAs including AC017002.2(P=0.039),cancer susceptibility 19(CASC19)(P=0.021),LINC00152(P=0.013),NONHSAT058834(P=0.007),NONHSAT007692(P=0.045),and ENST00000415991.1(P=0.045)showed significant differences in expression levels between the cancer tissue and paracancer tissue ***017002.2,NONHSAT058834,NONHSAT007692,and ENST000004159

关键词： lncRNA mRNA Expression profile Rectal cancer

CTX-M-14, CTX-M-24 and resistance in Escherichia coli and Klebsiella pneumoniae clinical isolates

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Chinese Medical Journal 2006年第2期119卷 160-164页

作者： XIONG Zi-zhong ZHU de-mei wang Fu ZHANG Ying-yuan Institute of Antibiotics Huashan Hospital Fudan University Shanghai 200040 China

Extended-spectrum β-lactamases （ESBLs） are the main cause of resistance to the third and forth-generation cephalosporins in Enterobacteriaceae, which are mediated by plasmids and can hydrolyze oxyiminoaminothiazolyl cephalosporins and monobactams. Most of ESBLs are mutants of the classical TEM and SHV types, with one or more amino-acid substitution（s） in the active site.

关键词： extended-spectrum β-lactamases CTX-M-14 CTX-M-24 Escherichia coli Klebsiella pneumoniae

Optimizing cooling approach of spiral coil for an electromagnetic steel teeming system of ladle in continuous casting production

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Journal of Iron and Steel Research International 2025年第1期32卷 85-94页

作者： Ming He Qing-wei wang Li-jia Zhao wang-zhong Mu Xing-an Liu Qiang wang College of Horticulture Shenyang Agricultural UniversityShenyang110866LiaoningChina Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Protected Horticulture(Ministry of Education) Shenyang Agricultural UniversityShenyang110866LiaoningChina department of Materials Science and Engineering KTH Royal Institute of TechnologyStockholm10044Sweden

To address the current issues with the conventional slide gate system utilized in the steel teeming process,a unique electromagnetic induction controlled automated steel teeming(EICAST)technology has been *** means of spiral coil in this technology is directly related to its service ***,heat transfer processes of air cooling and spray cooling were compared and ***,the impacts of water temperature,water flow rate and air flow rate were examined in order to maximize the spray cooling *** maintain coil temperature at a low value consistently throughout the entire thermal cycle process of the ladle,a combined cooling mode was finally *** simulation was applied to examine the coil temperature variation with different cooling systems and *** coil operation,spray cooling is said to be more *** controlling the water flow rate and air flow rate,the spray cooling effect is ***,water temperature has little or no impact when using spray *** cooling during the secondary refining process and spray cooling prior to coil operation are combined to further lower coil *** the direction of the spray cooling is from bottom to top,the coil temperature is lowered below 165℃.A practical induction coil cooling plan was provided for the EICAST technology’s production process.

关键词： Electromagnetic induction controlled automated steel teeming technology Spiral coil Spray cooling Heat transfer Continuous casting