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One stomach,two subtypes of carcinoma—the differences between distal and proximal gastric cancer

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Gastroenterology Report 2021年第6期9卷 489-504页

作者： Yuan Zhang Peng-Shan Zhang ze-yin Rong Chen Huang Department of Gastrointestinal Surgery Shanghai General HospitalShanghai Jiao Tong UniversityShanghaiP.R.China

Gastric cancer(GC)is one of the most common malignant tumors of the digestive tract,posing a significant risk to human *** the past 10 years,the pathological characteristics and the prognosis of GC have been determined based on the locations of the tumors that were then classified into two types—proximal and distal *** review focuses on the differences in epidemiology,etiology,cell source,pathological characteristics,gene expression,molecular markers,manifestations,treatment,prognosis,and prevention between proximal and distal GC to provide guidance and a basis for clinical diagnosis and treatment.

关键词： gastric cancer epidemiology pathology therapeutics prognosis

Notes and correspondence on ensemble-based three-dimensional variational filters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第8期14卷 634-641页

作者： Hong-ze LENG Jun-qiang SONG Fu-kang yin Xiao-qun CAO College of Computer National University of Defense Technology

Several ensemble-based three-dimensional variational (3D-Var) filters are compared. These schemes replace the static background error covariance of the traditional 3D-Var with the ensemble forecast error covariance, but generate analysis ensemble anomalies (perturbations) in different ways. However, it is demonstrated in this paper that they are all theoretically equivalent to the ensemble transformation Kalman filter (ETKF). Furthermore, a new method named EnPSAS is presented. The analysis shows that EnPSAS has a small condition number and can apply covariance localization more easily than other ensemble-based 3D-Var methods.

关键词： 3D-Var Ensemble Kalman filter (EnKF) Ensemble transformation Kalman filter (ETKF) Physical space analysis system (PSAS) Ensemble data assimilation

Effects of solution treatment on mechanical properties and microstructures of Al-Li-Cu-Mg-Ag alloy

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Journal of Central South University 2013年第8期20卷 2083-2089页

作者： YU Cheng yin Deng-feng ZHENG feng YU Xin-xiang School of Materials Science and Engineering Central South University Changsha 410083 China Key Laboratory of Nonferrous Materials of Ministry of Education (Central South University) Changsha 410083 China

Mechanical properties and microstructures of Al-Li-Cu-Mg-Ag alloy after solution treatments were investigated by means of optical microscopy （OM）, tensile test, hardness measurement and electrical conductivity test, differential scanning calorimetric （DSC）, energy dispersive X-ray （EDX）, scanning electron microscopy （SEM） and transition electron microscopy （TEM）, respectively The results show that both tensile strength and hardness increase first and then decrease with temperature at constant holding time of 30 min with maximum strength and hardness appearing at 520 ℃. Tensile strength, hardness and elongation of samples treated at 520 ℃ for 30 min are 566 MPa （σb）, 512 MPa （σ0.2）, HB 148 and 8.23% （δ）, respectively. There are certain amount of fine T1 （AI2CuLi） phase dispersing among AI substrates according to TEM images. This may result in mixed fracture morphology with trans-granular and inter-granular delamination cracks observed in SEM images.

关键词： Al-Li-Cu-Mg-Ag alloy solution treatment microstructure mechanical properties

The stable planar conformation of the γ-butyrolactone ring in solution

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Chinese Chemical Letters 2010年第2期21卷 187-190页

作者： Zhi Qiang feng Cheng Lie yin Institute of Materia Medica Chinese Academy of Medical Sciences Beijing 100050 China Department of Chemistry Beijing Normal University Beijing 100875 China

The conformations ofγ-butyrolactone ring in solution were deduced on the basis of ~1H NMR spectra of geminal protons of the butyrolactone ring.A series of optically pure(Z)-(-)-4-(1 -alkoxyl-1 -carbalkoxy-methylene)-... 详细信息

关键词： β-Methylene-γ-butyrolactone Planar conformation Envelope conformation

A Class of Preconditioners Based on Positive-Definite Operator Splitting Iteration Methods for Variable-Coefficient Space-Fractional Diffusion Equations

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Communications on Applied Mathematics and Computation 2021年第1期3卷 157-176页

作者： Jun-feng yin Yi-Shu Du School of Mathematical Sciences Tongji UniversityShanghai 200092China

After discretization by the finite volume method,the numerical solution of fractional diffusion equations leads to a linear system with the Toeplitz-like *** theoretical analysis gives sufficient conditions to guarantee the positive-definite property of the discretized ***,we develop a class of positive-definite operator splitting iteration methods for the numerical solution of fractional diffusion equations,which is unconditionally convergent for any positive ***,the iteration methods introduce a new preconditioner for Krylov subspace *** experiments verify the convergence of the positive-definite operator splitting iteration methods and show the efficiency of the proposed preconditioner,compared with the existing approaches.

关键词： Fractional diffusion equations Finite volume method Operator splitting Positive-definite

Commuting Dual Toeplitz Operators on the Harmonic Dirichlet Space

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Acta Mathematica Sinica,English Series 2016年第9期32卷 1099-1105页

作者： Jing Yu YANG yin yin HU Yu feng LU Tao YU School of Mathematical Statistics Chifeng University Chifeng 024000 P. R. China School of Mathematical Sciences Dalian University of Technology Dalian 116024 P. R. China

In this paper, we characterize the symbols for （semi-）commuting dual Toeplitz operators on the orthogonal complement of the harmonic Dirichlet space. We show that for φ ,ψ ∈ W1, ∞, SφSψ = SψSφ on （Dh）⊥ if and only if φ and ψ satisfy one of the following conditions：（1） Both φ and ψ are harmonic functions; （2） There exist complex constants α and β, not both O, such that φ = αφ＋β.

关键词： Dual Toeplitz operator harmonic Dirichlet space commutativity

Highly electronegative PtAu alloy for simultaneous hydrogen generation and ethanol upgrading

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Rare Metals 2023年第9期42卷 2949-2956页

作者： Kun yin Meng-Gang Li Yu-Guang Chao yin Zhou Shao-Jun Guo Fang-ze Liu Hong-Bo Li Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing100081China School of Materials Science and Engineering Peking UniversityBeijing100871China Advanced Research Institute of Multidisciplinary Sciences Beijing Institute of TechnologyBeijing100081China

Simultaneous electrochemical synthesis of high-valueadded chemicals and hydrogen is a promising technology for efficient carbon utilization and renewable energy storage. However, the lack of rational guidance for desi... 详细信息

关键词： hydrogen alloy hinder

Highly sensitive optical fiber temperature sensor based on resonance in sidewall of liquid-filled silica capillary tube

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Chinese Physics B 2019年第11期28卷 156-160页

作者： Min Li Biao feng Jiwen yin College of Physics and Intelligent Manufacturing Engineering Chifeng UniversityChifeng 024000China Department of Optoelectronics Science Harbin Institute of Technology at WeihaiWeihai 264209China

A highly sensitive optical fiber temperature sensor based on a section of liquid-filled silica capillary tube(SCT)between single mode fibers is proposed. Two micro-holes are drilled on two sides of SCT directly by using femtosecond laser micromachining, and liquid polymer is filled into the SCT through the micro-holes without any air bubbles and then sealed by using ultra-violet(UV) cure adhesive. The sidewall of the SCT forms a Fabry–Perot resonator, and loss peaks are achieved in the transmission spectrum of the SCT at the resonant wavelength. The resonance condition can be influenced by the refractive index variation of the liquid polymer filled in SCT, which is sensitive to temperature due to its high thermooptical coefficient(-2.98 × 10^-4℃^-1). The experimental result shows that the temperature sensitivity of the proposed fiber structure reaches 5.09 nm/℃ with a perfect linearity of 99.8%. In addition, it exhibits good repeatability and reliability in temperature sensing application.

关键词： optical fiber sensors liquid filling temperature measurement

Microstructure Variation of Cold Deformed MP159 Alloy during Aging

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Journal of Materials Science & Technology 1996年第2期12卷 109-113页

作者： Han, GW feng, D yin, M Yang, NS Central Iron and Steel Research Institute Beijing 100081 China

By comparing the relationship of room temperature yield strength with the reduction of cold rolled MP159 alloy before and after aging at 650 degrees C, and by means of TEM examination on the corresponding microstructures, the occurrence of fcc(alpha)-->hcp(epsilon) martensitic transition in MP159 alloy during cold deformation and the variation of the platelet epsilon phase during aging have been studied. The results show that the platelet a phase is really formed when the cold deformation reaches a critical value, and both the amount and the width of the platelet epsilon phase would further increase during 650 degrees C aging. The increases of the amount and the width of the platelet epsilon phase result in an additional increase of yield strength. Therefore, it is concluded that the additional hardening effect of MP159 alloy after aging is not only from the precipitation of Ni(3)X disperse phase but also from the volume fraction increase of the platelet epsilon phase. Further occurrence of the martensitic transition during aging may be due to the elimination of residual compression stress within matrix induced by the fcc(alpha)-->hcp(epsilon) transition during cold deformation.

关键词： Cobalt alloys