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Equilibrium Precipitation of Niobium Carbonitride in Austenite

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international Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 119-122页

作者： Fuming Wang Wenchao Li(Applied science School, University of science and Technology beijing, beijing 100083, China) Applied science School University of Science and Technology Beijing Beijing 100083 China

The equilibrium between niobium carbonitride and austenite has been studied. Experimentally, X-raydiffaction technique was adopted to verify that the precipitates have the same composition and structure. Theoretical-ly, Hillert and Staffansson's regular model about stoichimetric phase was used to describe the thermodynamic proper-ties of multi-component precipitate. Calculated results agree well with experimental values from literatures.

关键词： equilibrium niobium precipitate, austenite

A New Safety Electric Initiating System

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international Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 306-308页

作者： Daze Lin(Resource Engineering School, University of science and Technology beijing, beijing 100083, China) Univ of science and Technology Beijing Beijing China

Based on the analysis of weakness on the safety of traditional electric detonators, a BJ-l safety electric detonator initiatingsystem and its corresponding safe examination technique were successfully developed. By leading false foot wires and taking advantageof the transmitting frequency band of Mo-Zn ferrite, detonators in this new system can completely impede the direct induction of outsidecrosstalk that may cause casual firing in the ordinary as well as eleclromagnetic ones. Possible causality by lightning was discussed. Results are presented, of its safety tests on resistance to direct and alternating current, electrostatic, and crosstalk induced by damp leakagein saturated salty water.

关键词： electric detonator blasting engineering, electric initiating system, safety

Solutions for hydrodynamics of 5-and 10-fold symmetry quasicrystals

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Applied Mathematics and Mechanics(English Edition) 2016年第10期37卷 1393-1404页

作者： Hui CHENG Tianyou FAN Hao WEI School of Physics Beijing Institute of TechnologyBeijing 100081China School of science Hebei Engineering UniversityHandan 056038Hebei ProvinceChina

This study carries out a complete analysis of time-space solution of hy- drodynamics of pentagonal/decagonal quasicrystals. The behaviors of wave propagation for phonons and diffusion for phasons and coupling between phonon-phason fields are explored explicitly. Comprehensive discussion on physical time-space variations of all hydrodynamic field variables of the alloy quasicrystals is given. The computational spec- imen is simple, convenient in testing computational results, and provides a possibility that is easy to test experimentally. The quantitative results of mass density, viscosity ve- locities, phonon displacements, phason displacements, phonon stresses, phason stresses, viscosity stresses, and their time-space variations help us understand the motion of solid quasicrystals in a hydrodynamic condition （long-wavelength and low-frequency）. The analysis presented in this paper can be used for octagonal and dodecagonal quasicrys- tals and is easily extended to other two-dimensional quasicrystals and three-dimensional icosahedral quasicrystals. Some problems explored by the computational results are also discussed.

关键词： quasicrystal hydrodynamics mathematical solution finite difference method

Monitoring Multi-Temporal Changes of Lakes on the Tibetan Plateau Using Multi-Source Remote Sensing Data from 1992 to 2019:A Case Study of Lake Zhari Namco

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Journal of Earth science 2024年第5期35卷 1679-1691页

作者： Juan Wu Chang-Qing Ke Yu Cai Zheng Duan Jiangsu Provincial Key Laboratory of Geographic Information science and Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural ResourcesSchool of Geography and Ocean ScienceNanjing UniversityNanjing 210023China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023China Guangxi Water and Power Design institute Co. LtdNanning 530022China Collaborative Innovation Center of South China Sea Studies Nanjing 210023China Department of Physical Geography and Ecosystem science Lund UniversityLund 22362Sweden

Lake level,area and volume are sensitive indicators of climate *** present,many studies have focused on the interannual water balance of lakes,but lake level and area can change remarkably with seasons,especially for lakes with seasonal ice *** Namco,a seasonal frozen lake,was selected as an example to investigate its seasonal water ***-source altimetry and Landsat data were used to obtain the seasonal lake level and area from 1992 to 2019,and seasonal lake volume variations were also *** results indicated the average lake level,area and volume in autumn were the *** lake level,area,and volume experienced three turning points approximately in 2000,2010,and 2016,and showed an overall increasing trend from 1992 to 2019,with slopes of 0.15 m/year,2.17 km^(2)/year,and 0.14 km^(3)/year,*** lake area expanded significantly in autumn,which was related to the abundant *** time of land surface runoff,increased temperature,and evaporation may be the reason for the low lake level and volume in *** precipitation was the dominant factor of water balance,which explained 62.09%,62.43%,and 62.10%of the variations in lake level,area,and volume,respectively.

关键词： lake level lake area lake volume satellite altimetry landsat Zhari Namco hydrogeology

ON THE APPROXIMATION OF INCOMPRESSIBLE MISCIBLE DISPLACEMENT PROBLEMS IN POROUS MEDIA BY MIXED AND STANDARD FINITE VOLUME ELEMENT METHODS

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international Journal of Modeling, Simulation, and Scientific Computing 2013年第3期4卷 149-178页

作者： SARVESH KUMAR Department of Mathematics Indian institute of space science and Technology Thiruvananthapuram 695547 KeralaIndia

The incompressible miscible displacement problem in porous media is modeled by a coupled system of two nonlinear partial differential equations,the pressure–velocity equation and the concentration *** this paper,we present a mixed finite volume element method(FVEM)for the approximation of the pressure–velocity equation and a standard FVEM for the concentration equation.A priori error estimates in L^(∞)(L^(2))are derived for velocity,pressure and *** results are presented to substantiate the validity of the theoretical results.

关键词： Mixed methods finite volume element methods miscible displacement problems error estimates numerical experiments.

Association of tumor budding with clinicopathological features and prognostic value in stage III-IV colorectal cancer

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World Journal of Gastroenterology 2024年第2期30卷 158-169页

作者： Yue-Hao Luo Zhe-Cheng Yan Jia-Ying Liu Xin-Yi Li Ming Yang Jun Fan Bo Huang Cheng-Gong Ma Xiao-Na Chang Xiu Nie Department of Pathology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

BACKGROUND Tumor budding(TB)has emerged as a promising independent prognostic biomarker in colorectal cancer(CRC).The prognostic role of TB has been extensively studied and currently affects clinical decision making in patients with stage I and II ***,existing prognostic studies on TB in stage III CRC have been confined to small retrospective cohort ***,this study investigated the correlation among TB categories,clinicopathological features,and prognosis in stage III-IV CRC to further enhance the precision and individualization of treatment through refined prognostic risk *** To analyze the relationship between TB categories and clinicopathological characteristics and assess their prognostic value in stage III-IV CRC to further refine the prognostic risk stratification of stage III-IV *** The clinical data of 547 CRC patients were collected for this retrospective *** at the front edge of the tumor buds was counted according to the 2016 international Tumor Budding Consensus Conference *** Multivariate Cox proportional hazards regression analysis demonstrated that chemotherapy(P=0.004),clinical stage IV(P<0.001),≥4 regional lymph node metastases(P=0.004),left-sided colonic cancer(P=0.040),and Bd 2-3(P=0.002)were independent prognostic factors in patients with stage III-IV ***,the density of tumor infiltrating lymphocytes was higher in Bd 1 than in Bd 2-3,both in the tumor stroma and its invasive *** TB has an independent predictive prognostic value in patients with stage III-IV *** is recommended to complete the TB report of stage III-IV CRC cases in the standardized pathological report to further refine risk stratification.

关键词： Tumor budding Tumor infiltrating lymphocytes Colorectal cancer Survival analysis Prognosis

Burning rate analysis of laser controlled 5-aminotetrazole propellant

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Defence Technology（防务技术） 2023年第4期22卷 10-27页

作者： Nianbai He Ruiqi Shen Luigi T.DeLuca Lizhi Wu Wei Zhang Yinghua Ye School of Chemical Engineering Nanjing University of Science and Technology210094JiangsuChina institute of space Propulsion Nanjing University of Science and Technology210094JiangsuChina space Propulsion Laboratory(Ret) Department of Aerospace Science and TechnologyPolitecnico di Milano20156MilanItaly

As an innovative propulsion technique, laser augmented chemical propulsion(LACP) seems superior to the traditional ones. However, the corresponding combustion theories have still to be ascertained for LACP. Burning rate of 5-aminotetrazole(5-ATZ) propellant has been studied by testing pressed samples under different combustor pressures and laser powers. Based on micro computed tomography(Micro CT),an advanced thickness-over-time(TOT) method to characterize the regression of the produced nonplanar burning surface is established. Because of a shell structure covering the combustion surface,the burning rate of the implemented 5-ATZ propellant is not constant during laser ablation. Resorting to functional fitting, a new law of non-constant burning including the effect of the observed unique burning surface structures is proposed. Accordingly, applicable combustion conditions of 5-ATZ based propellants have been preliminarily speculated for future research activities.

关键词： 5-Aminotetrazole(5-ATZ) Laser-augmented chemical propulsion(LACP) Non-constant burning rate Micro computed tomography(MicroCT) Non-planar burning surface

Key factor for determining relation between radius and tidal deformability of neutron stars: Slope of symmetry energy

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Chinese Physics C 2020年第6期44卷 103-108页

作者： Nai-Bo Zhang Bin Qi Shou-Yu Wang Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China

The constraints on tidal deformability Λ of neutron stars were first extracted from GW170817 by LIGO and Virgo ***,the relationship between the radius R and tidal deformability Λ is still under *** an isospin-dependent parameterized equation of state(EOS),we study the relation between R andΛand its dependence on parameters of symmetry energy Esym and EOS of symmetric nuclear matter E0 when the mass is fixed at 1.4 M⊙,1.0 M⊙,and 1.8 M⊙.We find that,although the changes of high order parameters of Esym and E 0 can shift individual values of R1.4 and Λ1.4,the R1.4~Λ1.4 relation remains approximately at the same fitted *** slope L of the symmetry energy plays the dominant role in determining the R1.4~Λ1.4 *** investigating the mass dependence of the R~Λ relation,we find that the well fitted R~Λ relation for 1.4 M⊙ is broken for massive neutron stars.

关键词： neutron stars symmetry energy tidal deformability radius

Influence of yttrium on the structure and magnetostriction of Fe_(83)Ga_(17) alloy

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international Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 849-855页

作者： Xi-ming Xiao Xue-xu Gao Ji-heng Li Jian-xin Xie State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China School of Materials science and Engineering University of Science and Technology Beijing Beijing 100083 China

Polycrystalline Fe83Ga17 alloy rods with various amounts of yttrium were prepared by high vacuum induction melting. It is found that yttrium addition has a significant effect on the structure and magnetostriction of Fes3Ga17 alloy. The small addition of yttrium alters the solidification character and the grain shape of Fe83Ga17 alloy, and as a result, columnar grains with the 〈100〉 preferential direction are pro- duced. Yttrium addition improves the magnetostrictive performance of the as-cast Fes3Ga17 alloy. The magnetostriction values of the as-cast alloy with 0.32at% and 0.64at% yttrium addition go up to 119×10^-6 and 137×10^-6 under 15 MPa compressive stress, respectively. The energy dispersive spectroscopy （EDS） result shows that almost all of the yttrium atoms exist in the Y2Fe17-xGax phase. A small amount of this kind of secondary phase cannot obviously increase the saturate magnetic field.

关键词： gallium alloys iron alloys yttrium magnetostfiction supercooling polycrystallirte materials