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Distribution of Magnetic Flux Density in Soft-Contact EMCC Rectangular Mold

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Journal of Iron and Steel Research International 2006年第5期13卷 14-17,24页

作者： ZHANG Lin-tao WANG En-gang DENG An-yuan he Ji-cheng Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials Northeastern University Shenyang 110004 Liaoning China

The distribution of the magnetic flux density in a soft-contact electromagnetic continuous casting （EMCC） rectangular mold was investigated. The experimental results show that with an increase in electric power, the magnetic flux density increases. The position where the maximum magnetic flux density appears will shift up when the coil moves to the top of the mold. At the same time, the maximum magnetic flux density will increase and the effective acting range of electromagnetic pressure will widen. As a result, in practice, the coil should be placed near the top part of the mold. The meniscus should be controlled near the top part of the coil, as this not only remarkably improves the billet surface quality but also saves energy. With the same electric power input, the higher the frequency, the lower the magnetic flux density.

关键词： electromagnetic soft contact mold magnetic flux density continuous casting

On factorizable solution of the differential equation(f')~2-a_0(z)(f-a)1(z))~2f

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Chinese Science Bulletin 1997年第21期42卷 1779-1782页

作者： yuan Wenjun and he YuzanInstitute of Mathematics, Chinese Academy of Sciences, Beijing 100080, China Institute of Mathematics Chinese Academy of Sciences Beijing China

If the coefficients are transcendental, Bergweiler et al. proved that in all possible non-trivialfactorization f(z)=h(g(z)), the growth of the right factor g(z) can be controlled by thegrowth of the coefficients. In ref. [2], he and Laine proved a similar conclusion for two othertypical kinds of nonlinear differential equations. But for the following equation:

关键词： factorization growth order meromorphic function ordinary differential equation.

The mechanism for fuzzy-ball working fluids for controlling & killing lost circulation

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Chinese Science Bulletin 2010年第35期55卷 4074-4082页

作者： ZheNG LiHui KONG LingChen CAO yuan WANG HuiYun he XiaoQing MOE Key Laboratory of Petroleum Engineering China University of Pet'roleum Beijing 102249 China

Lost circulation controlling & killing material has been a focused issue since a long time ago.A novel leak resistance fluid with the raw materials such as SDS,SDBS,heS,PAM and proprietary productions has been developed from *** experiment and application shows that the new leak resistance fluid can plug leaking passage of different sizes *** with 1000 to 2000 time microscope,it is found that the working liquid contains a kind of spherical material which has the microstructure of "one core,two layers,and three membranes".When it is in a static state,the inside of the material looks like an airbag and the outside looks like some fuzzy things which has high gel *** when it is in a dynamic state,the fuzzy thing is cut or scattered and flow ability becomes much *** is the reason why it is called *** the diameter or the width of the leak passage is greater than the fuzzy-ball's,the fuzzy-ball accumulates in conical shape to decompose the working fluid pressure of liquid column to achieve blocking;when the diameter or the width of the leak passage is equivalent to the fuzzy-ball's,the fuzzy-ball changes from sphere to oval-shape to increase the resistance to the leak passage and plug the holes;when the diameter or the width of the leak passage is smaller than the fuzzy-ball's,the leaks could be blocked up by the non-permeable membrane formed by the gel of high strength in the working *** these cases,the leak passages of different sizes could be blocked comprehensively.

关键词：模糊工作流体十二烷基苯磺酸钠泄漏通道十二烷基硫酸钠通道宽度机制制球

A novel hydrophilic polystyrene-based beads for hydrophilic interaction chromatography by surface-initiated atom transfer radical polymerization

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Chinese Chemical Letters 2011年第2期22卷 245-248页

作者： Xiao Jun Dai yuan he Yin Mao Wei Bo Lin Gong Key Laboratory of Synthetic and Natural Function Molecule Chemistry of Ministry of Education College of Chemistry & Material Science Northwest University Xi'an 710069 China Key Laboratory of Energy & Chemical Engineering Ningxia University Yinchuan 750021 China Received 4 June 2010

A one-step procedure to hydrophilize monodisperse poly（chloromethyl-styrene-co-divinylbenzene） beads has been presented with 2-hydroxy-3-[4-（hydroxymethyl）-1H-1,2,3-triazol-1-yl]propy1 2-methylacrylate（HTMA） as monomer by surface-initiated atom transfer radical polymerization（SI-ATRP）.The length of the grafted poly（HTMA） chain was varied via controlling the ratio of HTMA to initiator on the surface of the *** these grafted beads as the stationary phase in hydrophilic interaction chromatography,good separation was obtained for nucleosides in the mobile phase of *** was also found that the retention time and selectivity of solutes showed a positive relationship with the length of the grafted poly（HTMA） chain.

关键词： Hydrophilic interaction chromatography Polystyrene-based beads Surface-initiated atom transfer radical polymerization 1,2,3-Triazole

Climatic and Edaphic Controls on Soil pH in Alpine Grasslands on the Tibetan Plateau,China:A Quantitative Analysis

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Pedosphere 2014年第1期24卷 39-44页

作者： JI Cheng-Jun YANG yuan-he HAN Wen-Xuan he Yan-Fang J.SMITH P.SMITH Department of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of Resources and Environmental Sciences China Agricultural University Institute of Biological & Environmental Sciences School of Biological SciencesUniversity of Aberdeen

Soil acidity is an important parameter that can regulate ecosystem structure and ***,a quantitative understanding of the relationships between soil pH and environmental factors remains *** this study,relationships of soil pH with both climatic and edaphic factors in alpine grasslands on the Tibetan Plateau,China were quantified using data obtained from a regional soil survey during *** results showed that soil pH decreased along the gradient of both mean annual temperature and ***,soil pH exhibited consistent negative correlations with soil moisture and silt ***,soil organic and inorganic carbon contents played opposite roles in shaping patterns of soil pH:the accumulation of soil organic matter led to higher soil acidity,while the existence of soil inorganic matter was favorable for maintaining higher soil *** variation partitioning analysis indicated that the combination of climatic and edaphic variables explained 74.3%of the variation in soil *** results suggest that soil pH could be predicted from routinely-measured variables,allowing a robust pedotransfer function to be *** pedotransfer function may facilitate land surface models to generate more reliable predictions on ecosystem structure and function around the world.

关键词： climate soil acidity soil inorganic carbon soil organic carbon soil texture

High-precision Measurements of Cosmic Curvature from Gravitational Wave and Cosmic Chronometer Observations

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Research in Astronomy and Astrophysics 2022年第8期22卷 198-205页

作者： yuan he Yu Pan Dong-Ping Shi Jin Li Shuo Cao Wei Cheng School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic and Electrical Engineering Chongqing University of Arts and SciencesChongqing 402160China Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China Department of Astronomy Beijing Normal UniversityBeijing 100875China

Although the spatial curvature has been measured with very high precision,it still suffers from the well-known cosmic curvature *** this paper,we use an improved method to determine the cosmic curvature,by using the simulated data of binary neutron star mergers observed by the second generation space-based DECi-hertz Interferometer Gravitational-wave Observatory(DECIGO).By applying the Hubble parameter observations of cosmic chronometers to the DECIGO standard sirens,we explore different possibilities of making measurements of the cosmic curvature referring to a distant past:one is to reconstruct the Hubble parameters through the Gaussian process without the influence of hypothetical models,and the other is deriving constraints onΩKin the framework of the non-flatΛcold dark matter *** is shown that in the improved method DECIGO could provide a reliable and stringent constraint on the cosmic curvature(ΩK=-0.007±0.016),while we could only expect the zero cosmic curvature to be established at the precision ofΔΩK=0.11 in the second model-dependent ***,our results indicate that in the framework of methodology proposed in this paper,the increasing number of well-measured standard sirens in DECIGO could significantly reduce the bias of estimations for cosmic *** a constraint is also comparable to the precision of Planck 2018 results with the newest cosmic microwave background(CMB)observations(ΔΩK≈0.018),based on the concordanceΛCDM model.

关键词： (cosmology:)cosmological parameters gravitational waves cosmology:observations

Direct fabrication of highly porous graphene/TiO_2 composite nanofibers by electrospinning for photocatalytic application

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Journal of Central South University 2018年第9期25卷 2182-2189页

作者： he yuan College of Environmental Science and Engineering Key Laboratory of Environmental Biology and PollutionHunan University

We reported the fabrication of highly porous graphene/TiO2 composite nanofibers in the form of a nonwoven mat by electrospinning followed by calcination in air at 450°*** graphene can uniformly disperse in highly porous TiO2 *** highly porous graphene/TiO2 composite nanofibers exhibited excellent catalytic *** new method for producing graphene/TiO2 composite nanofibers is versatile and can be extended to fabricate various types of metal oxide and graphene nanocomposites.

关键词： porous structure graphene titanium dioxide photocatalytic application

A Nine-modes Truncation of the Plane Incompressible Navier-Stokes Equations

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Communications in Mathematical Research 2011年第4期27卷 297-306页

作者： WANG he-yuan CUI YAN School of Science Liaoning University of Technology Jinzhou Liaoning 121001 Faculty of Information Science and Engineering Northeastern University Shenyang 110004

In this paper a nine-modes truncation of Navier-Stokes equations for a two-dimensional incompressible fluid on a torus is obtained. The stationary solutions, the existence of attractor and the global stability of the equations are firmly proved. What is more, that the force f acts on the mode ks and k7 respectively produces two systems, which lead to a much richer and varied phenomenon. Numerical simulation is given at last, which shows a stochastic behavior approached through an involved sequence of bifurcations.

关键词： the Navier-Stokes equation the strange attractor Lyapunov function,bifurcation chaos

Distribution and correlation of refractive parameters in children with different corneal curvatures in southeast China

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 713-720页

作者： Si-yuan he Ting he Meng-Yue Xu Ying-Jie Ni Chao-Yang Hong Ting Shen The Second Clinical College Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Ophthalmology Zhejiang Provincial People’s HospitalAffiliated People’s HospitalHangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Eye Center the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

AIM:To analyze the distribution of refractive status in school-age children with different corneal curvatures(CC)and the correlation between CC and refractive ***:A total of 2214 school-aged children of grade 4 in Hangzhou who were screened for school myopia were *** distance visual acuity(UCDVA),non-cycloplegic refraction,axial length(AL),horizontal and vertical corneal curvature(K1,K2)were measured and spherical equivalent(SE),corneal curvature radius(CCR)and axial length/corneal radius of curvature ratio(AL/CR)were ***he different CCRs,the patients were divided into the lower corneal curvature(LCC)group(CCR≥7.92)and the higher corneal curvature(HCC)group(CCRher divided into the normal AL subgroup and the long AL *** refractive parameters were compared to identify any differences between the two ***:Both SE and AL were greater in the LCC group(P=0.013,Phe prevalence of myopia was 38% in the LCC group and 44% in the HCC group(Phe proportion of children without screening myopia was higher in the LCC group(62%)than in the HCC group(56%).Among these children without screening myopia,the proportion of long AL in the LCC group(24%)was significantly higher than that in the HCC group(0.012%;Phe change of SE in the LCC group was less affected by the increase of AL than that in the HCC ***:School-aged children in the LCC group have a lower incidence of screening myopia and longer *** CC can mask SE reduction and AL growth to some extent,and the change of AL growth change more in children with low CC than high *** the onset of myopia,its growth rate is even faster than that after the onset of myopia.

关键词： school-aged children corneal curvature axial length spherical equivalent myopia screening