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Journal of Hydrodynamics 2020年第1期32卷 107-115页

作者： Xin Zhao Chao Wei shi-hua Yuan Science and Technology on Vehicle Transmission Laborator Bejing Institute of TechnologyBeijing 10081China

A new slip velocity model based on molecular potential theory and macro-force analysis,which is applied in Couette flow with pressure gradient,is built *** model is validated by later being introduced in hydrodynamic system to predict film distribution,which shows a good agreement with experimental data obtained from multi-beam intensity-based tests with Fe and Cu ball materials under accurate controlled temperature,load and different wall *** show that the slip length for Fe case is ignorable so it seems like no slip,but for Cu case,the slip length is large to make 20%discrepancy with no slip simulation and also behaves ***,during the experimental cases when both Fe and Cu ball velocities rise from-133 mm/s to 1330 mm/s,the slip velocity changes its direction with entrainment velocity and thus contributes to first enhance and then diminish the hydrodynamic film,but due to slip length on Cu case varying largely than that on Fe case,the film from Cu case and from Fe case has a clear cross-point between uh=80 mm/s and uh=220 m m/s(ub is the ball speed).The results above support strongly that Cu surface will lead to stronger slip than Fe case because of its smaller solid-liquid interaction,and obviously slip will influence hydrodynamic characteristics prominently.

关键词： Slip Couette flow with pressure gradient hydrodynamic characteristic

Microstructure and mechanical properties of ultralow carbon high-strength steel weld metals with or without Cu-Nb addition

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 120-130页

作者： Xing-hai Yang Xiao-hua Chen shi-wei Pan Zi-dong Wang kai-xuan Chen Da-yong Li Jun-wei Qin School of Material Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

Two types of ultralow carbon steel weld metals(with and without added Cu-Nb) were prepared using gas metal arc welding(GMAW) to investigate the correlation between the microstructure and mechanical properties of weld *** results of microstructure characterization showed that the weld metal without Cu-Nb was mainly composed of acicular ferrite(AF), lath bainite(LB), and granular bainite(GB).In contrast, adding Cu-Nb to the weld metal caused an evident transformation of martensite and grain *** weld metals had a high tensile strength(more than 950 MPa) and more than 17% elongation;however, their values of toughness deviated greatly,with a difference of approximately 40 J at-50℃.Analysis of the morphologies of the fracture surfaces and secondary cracks further revealed the correlation between the microstructure and mechanical *** effects of adding Cu and Nb on the microstructure and mechanical properties of the weld metal are discussed;the indication is that adding Cu-Nb increases the hardenability and grain size of the weld metal and thus deteriorates the toughness.

关键词： weld metal microstructure mechanical properties hardenability grain coarsening

NUMERICAL SIMULATION OF FLOW FIELDS IN A NATURAL DRAFT WET-COOLING TOWER

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Journal of Hydrodynamics 2007年第6期19卷 762-768页

作者： YANG Xiang-liang SUN Feng-zhong WANG kai shi Yue-tao WANG Nai-hua Heze Power Plant China Guodian Coporation Heze 274000 China School of Power and Energy Engineering Shandong University Jinan 250061 China

The flow field in the hyperbolic natural draft wet-cooling tower, which has great effects on the economy and security of power plant, was studied through numerical simulation. The mathematical model was established and analyzed in order to optimize the cooling-tower and to evaluate its efficiency. Various working conditions were considered and compared with each other, such as the circulating water flux, air temperature and tower resistance. It is concluded that when the cooling-tower runs without wind, there is a vacuum region inside the tower and the pressure rises with the increase of the tower height. Meanwhile, the inner flow field is axisymmetrical. The air velocity achieves its climax at the axis. It is also found that the effect of circulating water temperature is equivalent to that of the water flux.

关键词： cooling tower flow field circulation water flux circulation water temperature numerical simulation

Disruption of key GTPase regulators of endocytic recycling compartment does not interfere with soluble antigen crosspresentation in dendritic cells

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Cellular & Molecular Immunology 2016年第4期13卷 554-556页

作者： hua Rong Yan shi Department of Basic Medical Sciences School of Medicine Tsinghua-Peking Center for Life Sciences Tsinghua University Beijing China Department of Microbiology Immunology & Infectious Diseases and Snyder Institute University of Calgary Calgary Alberta Canada

Crosspresentation is of vital significance to immune surveillance. External antigens, soluble or solid, enter cells via endo-phagocytic vesicles and are eventually delivered to MHC class I molecules on the cell surface. After antigen uptake, there are three proposed pathways leading to surface MHC class I/peptide complex presentation. Direct translocation into the cytosol to use the conventional proteasome/TAP-dependent ER peptide loading; phagosome autonomous presentation following fusion with selected ER components; and endocytic recycling whereby antigens are processed within the endosome and form a complex with internalized MHC class I, for redelivery back to cell surface. Endocytic recycling compartment (ERC), a major perinuclear tubular network considered critical for slow endosomal recycling, has been suggested to be one route for crosspresentation. This pathway is particularly relevant for soluble antigen presentation, as the former two routes are mostly used to describe particulate antigen processing, involving phagosomes. Here we report the unexpected finding that disruption of key regulatory factors of ERC, small GTPase proteins ARF6,Rabl la, and Rab22a, had no effect on soluble ovalbumin (OVA) crosspresentation in a model dendritic cell system.

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Expression and radiolabeling of Cas9 protein

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Nuclear Science and Techniques 2017年第1期28卷 74-79页

作者： Qing-Long Yan hua-Ting Kong kai Xia Yu Zhang Ali Aladlbahi Ji-Ye shi Li-hua Wang Chun-Hai Fan Yun Zhao Ying Zhu Key Laboratory of Bio-Resources and Eco-Environment Ministry of Education College of Life Sciences Sichuan University Chengdu 610064 China Division of Physical Biology and Bioimaging Center CAS Key Laboratory of Interfacial Physics and TechnologyShanghai Institute of Applied Physics Chinese Academy of Sciences Jiading Campus Shanghai 201800 China Chemistry Department King Saud University Riyadh 11451Saudi Arabia UCB Pharma Slough SL1 3WE UK

As a robust platform for genome editing,CRISPR/Cas9 is currently being explored for engineering biology or therapeutics,yet means for quantitative detection of Cas9 proteins remain to be fully ***,we expressed Cas9 proteins and developed a novel detection method that traced Cas9 based on radiolabeled *** optimizing the reaction conditions of reaction time,temperature and cycles,we obtained ^(125)I-Cas9 of high labeling *** prepared ^(125)I-Cas9 was stable in various media and preserved excellent genome editing ***,our strategy provides a convenient and efficient tool for further tracing biological behaviors of Cas9 proteins in living systems.

关键词： Cas9 Radiolabeling 125I labeling yield Stability

The DFF-PSP Iterative Separation and Theoretical Bound for PCMA with Long Memory

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Chinese Journal of Electronics 2016年第5期25卷 880-885页

作者： CUI Penghui JIANG hua CAO kai LI Taozhu National Digital Switching Engineering Technological Research Center

This paper proposes the Decision feedbackfeedforward per-survivor processing(DFF-PSP) iterative separation algorithm and the Monte Carlo integrationbased method to compute the theoretical bound for Paired carrier multiple access(PCMA) Single channel blind separation(SCBS) which is highly complex with long memory. The truncated PSP is employed while the pre- and post- cursors are disregarded to control the *** delayed decisions feedforward and local decisions feedback filters are designed to process the pre- and postcursors. The Bit-interleaved code modulation iterative decoder(BICM-ID) is combined with the second soft decision of the truncated PSP to obtain a better *** mixture signal model is regarded as a Multiple-access channel(MAC) with memory, and the theoretical performance bound is obtained via entropy inequality, Monte Carlo integration and Fano inequality. Simulation results show that the DFF-PSP iterative separation provides the good tradeoff between complexity and performance.

关键词： Paired carrier multiple access(PCMA) Single channel blind separation(SCBS) Decision feedbackfeedforward Per-survivor processing Bit-interleaved code modulation iterative decoder(BICM-ID) Multiple-access channel(MAC) Theoretical performance bound

Power Allocation for Wireless Powered MIMO Transmissions with Non-Linear RF Energy Conversion Models

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China Communications 2017年第2期14卷 57-64页

作者： Liqin shi Liqiang Zhao kai Liang State Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 China

We study a radio frequency(RF) wireless energy transfer(WET) enabled multiple input multiple output(MIMO) system. A time slotted transmission pattern is considered. Each slot can be divided into two phases, downlink(DL) WET and uplink(UL) wireless information transmission(WIT). Since energy conversion efficiency of the energy harvesting circuits are ***, the conventional linear model leads to a mismatch for resource allocation. In this paper, the power allocation algorithm considering the practical *** energy harvesting circuits is studied. The optimization problem is formulated to maximize the energy efficiency of system with multiple constraints, i.e., the transmission power, the received power and the minimum harvested energy, which is a *** problem. We transform the objective function from fractional form into an equivalent objective function in subtractive form and provide an iterative power allocation algorithm to achieve the optimal solution. Numerical results show that our proposed algorithm with the *** RF energy conversion models can achieve much better performance than the algorithm with the conventional linear model.

关键词： WET MIMO non-linear energy conversion model energy efficiency power allocation

Classical Communication Cost and Probabilistic Remote Preparation of Four-Particle Entangled W State

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Communications in Theoretical Physics 2009年第3期51卷 411-418页

作者： HOU Kui shi Shou-hua School of Physics ＆ Material Science Anhui University Hefei 230039 China

We present a scheme for probabilistic remote preparation of the four-particle entangled W state by using four partial entangled two-particle states as the quantum channel. In this scheme, if Alice （sender） performs four-particle projective measurements and Bob （receiver） adopts some appropriate unitary operation, the remote state preparation can be successfully realized with certain probability. The classical communication cost is also calculated. However, the success probability of preparation can be increased to 1 for four kinds of special states.

关键词： remoter state preparation classical communication cost four-particle entangled W state projective measurement

Text Mining and Analysis of Treatise on Febrile Diseases Based on Natural Language Processing

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World Journal of Traditional Chinese Medicine 2020年第1期6卷 67-73页

作者： kai Zhao Na shi Zhen Sa hua-Xing Wang Chun-hua Lu Xiao-Ying Xu School of Traditional Chinese Medicine Beijing University of Chinese Medicine School of Life Science Beijing University of Chinese Medicine Beijing 100029China

Objective:With using natural language processing (NLP) technology to analyze and process the text of "Treatise on Febrile Diseases (TFDs)"for the sake of finding important information, this paper attempts to apply NLP in the field of text mining of traditional Chinese medicine (TCM)literature. Materials and Methods:Based on the Python language, the experiment invoked the NLP toolkit such as Jieba, nltk, gensim,and sklearn library, and combined with Excel and Word software. The text of "TFDs" was sequentially cleaned, segmented, and moved the stopped words, and then implementing word frequency statistics and analysis, keyword extraction, named entity recognition (NER) and other operations, finally calculating text similarity. Results:Jieba can accurately identify the herbal name in "TFDs." Word frequency statistics based on the word segmentation found that "warm therapy" is an important treatment of "TFDs." Guizhi decoction is the main prescription,and five core decoctions are identified. Keyword extraction based on the term "frequency-inverse document frequency" algorithm is *** accuracy of NER in "TFDs" is about 86%;latent semantic indexing model calculating the similarity,"Understanding of Synopsis of Golden Chamber (SGC)" is much more similar with "SGC" than with "TFDs." The results meet expectation. Conclusions:It lays a research foundation for applying NLP to the field of text mining of unstructured TCM literature. With the combination of deep learning technology,NLP as an important branch of artificial intelligence will have broader application prospective in the field of text mining in TCM literature and construction of TCM knowledge graph as well as TCM knowledge services.

关键词： Knowledge discovery natural language processing text mining traditional Chinese medicine literature treatise on febrile diseases

KAM Tori for the Derivative Quintic Nonlinear Schrodinger Equation

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Acta Mathematica Sinica,English Series 2020年第2期36卷 153-170页

作者： Dong Feng YAN Guang hua shi School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001P.R.China College of Mathematics and Statistics Hu fnan Normal UniversityChangsha 410006P.R.China

This paper is concerned with one-dimensional derivative quintic nonlinear Schrodinger equation,iut—uxx+i(|u|4u)x=0,x *** existence of a large amount of quasi-periodic solutions with two frequencies for this equation is *** proof is based on partial Birkhoff normal form technique and an unbounded KAM *** mention that in the present paper the mean value of u does not need to be zero,but small enough,which is different from the assumption(1.7)in Geng-Wu[***.、53,102702(2012)].

关键词： Derivative nonlinear Schrodinger equation KAM theorem quasi-periodic solutions BirkhofF normal form