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Study on the area ratio of Nb–Sn target for the preparation of Nb_(3)Sn films

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Radiation Detection Technology and Methods 2019年第3期3卷 289-293页

作者： Shuang-Kai chen yu-chen yang Di-Zhou Guo Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Introduction Niobium is extremely important in SRF cavities because of its superconducting ***,there are some intrinsic limits of Nb cavities that cannot meet the requirements of future *** is therefore of utmost importance to look into materials offering SRF performances beyond ***3Sn is the most promising *** our work,the cathode target is cylindrical and rotatable,containing both Nb and Sn elements,which are simultaneously charged,aiming to explore the area ratios of the two elements required in the cathode target by simulation and experiments,*** work will provide the basis for the subsequent Nb3Sn cathode target *** and experiments In the simulation,we calculated stoichiometric ratio and sputtering yield to obtain the area ratios of Nb and *** the experiment,we calculated the rotation rate of the target,deposition thickness of films on substrates and deposition rate to obtain the area ratio of Nb and *** In conclusion,we compared the simulation and experimental results and found that they are in good *** simulation and experimental results also showed that the area ratio of Nb to Sn in the target is close to 9:*** results lay the foundation for the subsequent Nb3Sn cathode target fabrication and multilayer deposition of Nb3Sn thin films.

关键词： Magnetron sputtering Nb3Sn deposition simulation SEM

NUMERICAL RESEARCH ON WATER GUIDE BEARING OF HYDRO-GENERATOR UNIT USING FINITE VOLUME METHOD

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Journal of Hydrodynamics 2007年第5期19卷 635-642页

作者： PENG yu-cheng chen Xi-yang ZHANG Ke-wei HOU Guo-xiang School of Energy and Power. Engineering Huazhong University of Science and Technology Wuhan 430074 China School of Traffic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

With the consideration of the geometry of tilting pad journal bearing, a new form of the Reynolds equation was derived in this article. The film thickness, the squeeze motion of the journal and the rotation motion of the pad were explicitly contained in the equation. Based on this equation, together with the equilibrium equation of pad pivot, the water guide bearing used in the Gezhouba 10 F hydro-generator unit was numerically researched. The new Reynolds equation for the lubricating film was solved using Finite Volume （FV） discretization, Successive Over-Relaxation （SOR） iteration method and C＋＋ code are included. According to the numerical solution, and the stability of the film and the influences of the film thickness, the journal squeeze effect and the pad rotation effect on film force were discussed. The results indicate that the squeeze effect can not be neglected, although the rotation effect is negligible for both low-speed and high-speed bearings, so the computing time could be greatly reduced.

关键词： hydro-generator unit Reynolds equation,tilting pad journal bearing Finite Volume (FV) method

NUMERICAL STUDY OF CAVITATION ON THE SURFACE OF THE GUIDE VANE IN THREE GORGES HYDROPOWER UNIT

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Journal of Hydrodynamics 2010年第5期22卷 703-708页

作者： PENG yu-cheng chen Xi-yang CAO Yan HOU Guo-xiang School of energy and Power Engineering Huazhong University of Science and Technology Wuhan 430074 China College of Electronic Information Engineering Wuhan Polytechnic Wuhan 430074 China School of Traffic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Large-area erosions such as rust and obvious cavitation were found on the surface of the guide vane in Three Gorges hydropower units. A numerical explanation of the cavitation is given in this article. At first, based on the characteristic performance curves of the prototype hydro-turbine supplied by ALSTOM together with the actual operating conditions, an operating point is chosen for numerical analysis using the Reynolds-Averaged Navier-Stokes （RANS） equations. The flow passages from the inlet of the spiral case to the outlet of the draft tube are included in the computational domain. The results show that the static pressure on the guide vane surface is much higher than the critical pressure of cavitation. Secondly, a tiny protrusion on the guide vane surface is considered and the problem is simplified to a 2-D problem to study the local detailed flow near the guide vane surface. The protrusion is 0.5 mm in height and is 5.0 mm in width. On the basis of the results of RANS simulations, the 2-D problem is studied using the Large Eddy Simulation （LES）. It is shown that there exists a region in which the static pressure reaches a level below the vapor pressure of the water. Thirdly, a cavitation model is included for the 0.5 mm protrusion case and another tiny pit case, with a tiny pit 0.3 mm in depth and 1.0 mm in width. The results show that vapor bubble exists at the protrusion entrance and the pit exit as the low pressure regions.

关键词： cavitation guide vane numerical analysis

Precise gradient separation of nanoparticles using reduced graphene oxide-polyoxomolybdate membranes

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Science China Chemistry 2025年第1期68卷 209-216页

作者： Yixin yang Wanlei Zhao Ruoxuan Zheng Hongqiang Li Wei chen yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Quzhou Institute for Innovation in Resource Chemical Engineering

The purification and size sieving of nanoparticles （NPs） represents a significant scientific ***,the r GO-polyoxometalates (POMs=PMo12,Mo132and Mo368) membranes were fabricated successfully via a simple and scalable POMsassisted in-situ photoreduction *** the mass ratio of r GO to PMo12was 1:30,the resultant r GO-PMo12membranes with highly ordered and uniform nanochannels of 1.0 nm can be obtained,which showed an accurate carbon quantum dots（CQDs） separation with a cut-off size approximately 1.0 *** increase of the size of the interlayered POMs from PMo12（1.0 nm）,{Mo132}（2.9 nm） to{Mo368}（3.8 nm）,the resultant r GO-PMo12,r GO-Mo132and r GO-Mo368exhibited precise gradient separation of CQDs and Au nanoparticles by size exclusion *** results pave a promising way to construct new twodimensional （2D） membranes for highly efficient size-selective separation.

关键词： reduced graphene oxide polyoxometalates membranes gradient separation nanoparticles

Fabrication of Novel Scaffolds Containing Collagen-I/Polylactic Acid/Nanohydroxyapatite via Co-electrospinning Methods

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Chemical Research in Chinese Universities 2010年第4期26卷 662-666页

作者： ZANG Jun-ting QI Xin LI Shu-qiang LI Dong-song GONG yu-bao yang chen XU Feng LIU Jian-guo Department of Bone and Joint Surgery First Hospital of Jilin University Changchun 130021 P R. China

A novel scaffold containing collagen-I/polylactic acid（PLA）/nanohydroxyapatite（nHA） was prepared via co-electrospinning method. Different target substrates were used to improve the collection efficiency of this scaffold. The properties of the novel scaffold were compared with those of conventionally prepared ones. Compared to con- ventional method, the modified method was more efficient in producing the scaffold. Moreover, the porosity, thickness, and morphology of the novel scaffold were better than those of scaffolds prepared by conventional methods. The properties of collagen-I, collagen-I/PLA and collagen-I/PLA/nHA scaffolds were also compared. Diameters of the electrospun fibers ranged from 180 to 405 nm, and roughness was present on the surface of the fibers due to the deposition of crystals of nHA along the long axis of the fibers. The fibers of the collagen-I/PLA/nHA scaffold and the fibers of natural bone tissue had similar structure.

关键词： Electrospinning Collagen-I PLA Nanohydroxyapatite

Engine Misfire Fault Detection Based on the Channel Attention Convolutional Model

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Computers, Materials & Continua 2025年第1期82卷 843-862页

作者： Feifei yu Yongxian Huang Guoyan chen Xiaoqing yang Canyi Du Yongkang Gong School of Mechatronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China School of Automotive and Transportation Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China

To accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENET),for classifying engine vibration signals and precisely pinpointing misfire *** the experiment,we established a total of 11 distinct states,encompassing the engine’s normal state,single-cylinder misfire faults,and dual-cylinder misfire faults for different *** collection was facilitated by a highly sensitive acceleration signal collector with a high sampling rate of 20,*** collected data were methodically divided into training and testing sets based on different experimental groups to ensure generalization and prevent overlap between the two *** results revealed that,with a vibration acceleration sequence of 1000 time steps(approximately 50 ms)as input,the SENET model achieved a misfire fault detection accuracy of 99.8%.For comparison,we also trained and tested several commonly used models,including Long Short-Term Memory(LSTM),Transformer,and Multi-Scale Residual Networks(MSRESNET),yielding accuracy rates of 84%,79%,and 95%,*** underscores the superior accuracy of the SENET model in detecting engine misfire faults compared to other ***,the F1 scores for each type of recognition in the SENET model surpassed 0.98,outperforming the baseline *** analysis indicated that the misclassified samples in the LSTM and Transformer models’predictions were primarily due to intra-class misidentifications between single-cylinder and dual-cylinder misfire *** delve deeper,we conducted a visual analysis of the features extracted by the LSTM and SENET models using T-distributed Stochastic Neighbor Embedding(T-SNE)*** findings revealed that,in the LSTMmodel,data points of the same type tended to cluster together with significant ***,in the SENET model,data points of various types were more widely and evenly dispersed,demonstra

关键词： Channel attention SENET model engine misfire fault fault detection

Gene Expression Profile Identifies LncRNA AL355974.3 As a Potential Glioma Biomarker

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Current Medical Science 2024年第5期44卷 1047-1057页

作者： Hao-tian LU yu-yang chen Yong-jia yu Xing-sheng LIAO Hui LIANG Lun LIANG Pan-lin MO Xin-kai HUANG Shuai DING Chang LIU Da-qin FENG Department of Neurosurgery The First Affiliated HospitalGuangxi Medical UniversityNanning530021China

Objective Glioma is a central nervous system tumor arising from glial *** significant advances in diagnosis and treatment,most patients with high-grade gliomas have a poor *** studies have shown that long noncoding RNAs(lncRNAs)may play important roles in the development,progression and treatment of many tumors,including *** targeted therapy may be a new direction for the adjuvant treatment of ***,we hope that by studying differentially expressed lncRNAs(DElncRNAs)in glioma,we can discover lncRNAs that can serve as biomarkers for glioma and provide better therapeutic modalities for glioma *** First,the expression of lncRNAs in 5 normal brain(NB)tissues and 10 glioma tissues was examined by RNA sequencing(RNA-seq).Next,we performed Kaplan-Meier analysis of data from The Cancer Genome Atlas(TCGA)database to assess the prognostic value of these ***,functional analysis of the DElncRNAs was performed by means of Gene Ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway *** RNA sequencing analysis revealed 85 upregulated miRNAs and 71 downregulated lncRNAs in low-grade glioma(LGG)and 50 upregulated lncRNAs and 70 downregulated lncRNAs in glioblastoma(GBM).Among them,AL355974.3 was the most upregulated ***00632 was the most downregulated ***,LGG patients with higher AL355974.3 expression had worse overall survival according to Kaplan-Meier analysis of the TCGA ***,bioinformatics analysis revealed that the target genes of these DElncRNAs were enriched in various biological processes and signaling pathways,such as cell metabolic and developmental *** Our findings provide evidence that AL355974.3 may be a new biomarker for glioma.

关键词： glioma long noncoding RNAs biomarker RNA sequencing

A Novel Self-Supervised Learning Network for Binocular Disparity Estimation

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 209-229页

作者： Jiawei Tian yu Zhou Xiaobing chen Salman A.AlQahtani Hongrong chen Bo yang Siyu Lu Wenfeng Zheng Department of Computer Science and Engineering Major in Bio Artificial IntelligenceHanyang UniversityAnsan-si15577Republic of Korea School of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11574Saudi Arabia School of Automation University of Electronic Science and Technology of ChinaChengdu610054China

Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical *** study proposes a novel end-to-end disparity estimation model to address these *** approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting *** study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and *** model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video *** results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing ***,the model exhibited faster convergence during training,contributing to overall performance *** study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.

关键词： Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation

Research progress in the use of bifidobacteria for the treatment of colorectal cancer

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Gastroenterology & Hepatology Research 2022年第3期4卷 30-33页

作者： yu-Ting Zhao Zhi-Hui Cai yu-chen yang Graduate School Inner Mongolia Medical UniversityHohhot 010017China Department of Medical Oncology Inner Mongolia People’s HospitalHohhot 010017China

Colorectal cancer has high morbidity and mortality rates;therefore,developing new therapeutic drugs and methods for it is *** is increasing evidence that intestinal flora plays a vital role in maintaining intestinal homeostasis and therefore,in the development of colorectal *** such,therapeutic approaches using probiotics such as Bifidobacterium lactis to regulate intestinal flora are expected to represent a new treatment strategy for colorectal *** article introduces and compares the development status of conventional therapies for colorectal cancer,primarily targeted therapy and immunotherapy,the relationship between intestinal flora and colorectal cancer,and the research and application of Bifidobacterium bifidum in colorectal cancer treatment to provide a reference for its clinical application.

关键词： colorectal cancer treatment intestinal flora bifidobacteria