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Thermodynamic Calculation and MnS Solubility of Mn-Ti Oxide Formation in Si-Mn-Ti Deoxidized Steel

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Journal of Iron and Steel Research International 2010年第2期17卷 10-16页

作者： ZHUO Xiao-jun WANG Yuan-qi WANG Xin-hua lee Hae-geon Technology Management Section China Minmetals Corporation Beijing 100044 China Department of Scienee and Technology Information China Iron and Steel Research Institute Group Beijing 100081 China Metallurgieal and Ecological Engineering Sehool University of Science and Technology Beijing Beijing100083 China Graduate Institute of Ferrous Teehnology Pohang University of Science and TechnologyPohang 790-784 South Korea

Mn-Ti oxides in Si-Mn-Ti deoxidized steels after cooling in the furnace were investigated. The composition and morphology of inclusions were analyzed by using FE-SEM with EDS. Mn-Ti oxides were found to be effective sites to induce intragranular ferrite formation. The thermodynamic calculation was employed to interpret the critical condition for Mn-Ti oxide formation. Mn-Ti oxide formation was controlled not only by Mn and Ti content, but also by total oxygen content in steel. When the Mn and Ti contents were around 1.5% and 0. 005% --0.01%, respectively, Mn-Ti oxide could form as the total oxygen content was 0. 001%- 0. 002 %. The experimental results were in good agreement with thermodynamic calculation results. Also, MnS solubilit：（ was examined in Mn-Ti oxide inclusion system. With an increase of MnO content in Mn-Ti oxide, MnS solubility in the oxides increased. MnS precipitation benefited from high MnO content in Mn-Ti oxide.

关键词： Si-Mn-Ti deoxided steel Mn-Ti oxide MnS intragranular ferrite thermodynamic calculation

Formation and Thermal Stability of Large Precipitates and Oxides in Titanium and Niobium Microalloyed Steel

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Journal of Iron and Steel Research International 2008年第3期15卷 70-77页

作者： ZHUO Xiao-jun WOO Dae-hee WANG Xin-hua lee Hae-geon Metallurgical and Ecological Engineering School University of Science and Technology Beijing Belling 100083 China Graduate Institute of Ferrous Technology Pohang University of Science and Technology Pohan4g 790 784 South Korea

As-cast CC slabs of microalloyed steels are prone to surface and sub-surface cracking. Precipitation phenomena initiated during solidification reduce ductility at high temperature. The unidirectional solidification unit is employed to simulate the solidification process during continuous casting. Precipitation behavior and thermal stability are systematically investigated. Samples of adding titanium and niobium to steels have been examined using field emission scanning electron microscope （FE-SEM）, electron probe X-ray microanalyzer （EPMA）, and transmission electron microscope （TEM）. It has been found that the addition of titanium and niobium to high-strength low-alloyed （HSLA） steel resulted in undesirable large precipitation in the steels, i. e. , precipitation of large precipitates with various morphologies. The composition of the large precipitates has been determined, The effect of cooling rate on （Ti, Nb）（C, N） precipitate formation is investigated. With increasing the cooling rate, titanium-rich （Ti,Nb）（C,N） precipitates are transformed to niobium-rich （Ti,Nb）（C,N） precipitates. The thermal stability of these large precipitates and oxides have been assessed by carrying out various heat treatments such as holding and quenching from temperature at 800 and 1 200℃. It has been found that titanium-rich （Ti,Nb）（C,N） precipitate is stable at about 1 200 ℃ and niobium-rich （Ti,Nb）（C,N） precipitate is stable at about 800 ℃. After reheating at 1 200℃ for 1 h, （Ca,Mn）S and TiN are precipitated from Ca-Al oxide. However, during reheating at 800 ℃ for l h, Ca-Al-Ti oxide in specimens was stable. The thermodynamic calculation of simulating the thermal process is employed. The calculation results are in good agreement with the experimental results.

关键词： carbonitride microsegregation dendritic region unidirectional solidification heat treatment thermal stability

BOTTOM SHEAR STRESS UNDER WAVE-CURRENT INTERACTION

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Journal of Hydrodynamics 2008年第1期20卷 88-95页

作者： LIANG Bing-chen LI hua-jun lee Dong-yong College of Engineering Ocean University of China Qingdao 266100 China Coastal and Harbour Engineering Research Center Korea Ocean Research and Developmcnt Institute Ansan Korea

The present work adopts the COHERENS-SWAN model developed by the first author through coupling three-dimensional hydrodynamic model （COHERENS） and third-generation wave model （SWAN）. Inside the COHERENS-SWAN, the SWAN is regarded as a subroutine and the time- and space-varying current velocity and surface elevation are obtained from the COHERENS. Wave-enhanced bottom shear stress, wave induced surface mixing length and wave dependent surface drag coefficient have been introduced into the COHERENS. Secondly, as wave-enhanced bottom shear stress （＂bottom shear stress＂ described as BSS sometimes in this article） is concerned, a modified bottom shear stress Grant and Madsen model which introduces random wave field is given and introduced to COHERENS-SWAN. COHERENS-SWAN is also adopted to simulate three-dimensional flow in the Yellow River Delta with wave-current co-existing. Four numerical experiments were given to study the effects of wave-current interaction on enhancing bottom shear stress. The simulated current velocities, wave height and wave period match well with field measurement data. The simulated significant wave height and wave period for the case with considering the effects of current can give better agreement with measurement data than the case without involving the effects of current. The introduction of random wave generates lower the bottom shear stress than the case without introducing it. There are obvious differences between bottom shear stress of two way interaction and one way interaction. Velocity field obtained by the COHERENS-SWAN is reasonable according to previous studies and measurements.

关键词： Yellow River Delta COHERENS SWAN wave-current interaction bottom shear stress

FACTORS OF 3GWC SYSTEMS FOR DRAWING UP CUSTOMIZED STRATEGIES OF PROMOTION

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Journal of Systems Science and Systems Engineering 2011年第3期20卷 365-381页

作者： Hsin-Pin FU Hwan-Yann SU Fang-hua WANG Ching-Yi CHANG Hung-Hsuan lee Department of Marketing and Distribution Management National Kaohsiung First University of Science and Technology Kaohsiung Taiwan China Department of Asia-Pacific Industrial and Business Management National University of Kaohsiung Taiwan China Antai College of Economics ＆ Management Shanghai Jiao Tong University Shanghai China Antai College of Economics ＆ Management Shanghai Jiao Tong University Shanghai China Institute of Management National Kaohsiung First University of Science and Technology Taiwan China

This study utilizes fuzzy analytic hierarchy process （FAHP） to analyze decision-making pattems with regard to third-generation wireless communications （3GWC） service adoption, and to provide customized strategic recommendations to suppliers of 3GWC services regarding marketing and resource allocation in the context of the Chinese 3GWC market. First of all, a three-layer hierarchy of 3GWC adoption factors is developed by referring to the relevant literature and industry reports. A questionnaire of pairwise comparisons in the fuzzy AHP format is then designed and distributed to experts familiar with the handset market in Shanghai, China. These surveys are then analyzed using fuzzy AHP to establish an understanding of the weights and impacts of the various factors. The results show that the four most important factors for the adoption of 3GWC systems are：（i） handset price and voice and data-transmission fees; （ii） handset aesthetics; （iii） personalization; and （iv） network coverage. These findings suggest that providers of such services should customize and diversify the content/applications they offer and ensure the speed and reliability of network access. In addition, handset designs should be in accordance with consumer demands. If these steps can be achieved, then consumers will adopt 3GWC services more rapidly.

关键词： 3GWC (third generation mobile) adoption factors FAHP

Plexiform fibromyxoma:Review of rare mesenchymal gastric neoplasm and its differential diagnosis

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World Journal of Gastrointestinal Oncology 2021年第5期13卷 409-423页

作者： Mustafa Erdem Arslan hua Li Zhiyan Fu Timothy A Jennings Hwajeong lee Pathology and Laboratory Medicine Albany Medical CenterAlbanyNY 12208United States

Plexiform fibromyxoma(PF)is a very rare mesenchymal neoplasm of the stomach that was first described in 2007 and was officially recognized as a subtype of gastric mesenchymal neoplasm by World Health Organization(WHO)in ***,PF is characterized by a plexiform growth of bland spindle to ovoid cells embedded in a myxoid stroma that is rich in small *** lesion is usually *** mucosal and vascular invasion have been documented,no metastasis or malignant transformation has been *** pathogenesis is largely unknown and defining molecular alterations are not currently *** are other mesenchymal tumors arising in the gastrointestinal tract that need to be differentiated from PF given their differing biologic behaviors and malignant *** mimics with spindle cells include gastrointestinal stromal tumor,smooth muscle tumor,and nerve sheath *** mimics with myxoid stroma include myxoma and aggressive *** alterations that have been described in a subset of PF may be seen in gastroblastoma and malignant epithelioid tumor with gliomaassociated oncogene homologue 1(GLI1)*** recent increase in publications on PF reflects growing recognition of this entity with expansion of clinical and pathologic findings in these *** we provide a review of PF in comparison to other mesenchymal tumors with histologic and molecular resemblance to raise the awareness of this enigmatic ***,we highlight the challenges pathologists face when the sample is small,or such rare entity is encountered intraoperatively.

关键词： Plexiform Fibromyxoma Gastrointestinal Mesenchymal Neoplasm Stomach

Non-Hermitian pseudo-gaps

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Science Bulletin 2022年第7期67卷 685-690页

作者： Linhu Li Ching hua lee Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-sen University(Zhuhai Campus)Zhuhai 519082China Department of Physics National University of SingaporeSingapore 117551Singapore

The notion of a band gap is ubiquitous in the characterization of *** interesting are pseudo-gaps,which are enigmatic regions of very low density of states that have been linked to novel phenomena like high temperature *** this work,we discover a novel origin for pseudo-gaps when boundaries are introduced in a non-Hermitian *** generically occurs due to the interference between two or more asymmetric pumping channels,and possess no analog in Hermitian ***,it can be visualized as being created by divergences of spectral flow in the complex energy plane,analogous to how sharp edges creates divergent electric fields near an electrical conductor.A non-Hermitian pseudo-gap can host symmetry-protected mid-gap modes like ordinary topological gaps,but the mid-gap modes are extended instead of edge-localized,and exhibit extreme sensitivity to symmetry-breaking ***,pseudo-gaps can also host an integer number of edge modes even though the pseudo-bands possess fractional topological windings,or even no well-defined Chern number at all,in the marginal case of a phase transition *** conventional notions of topological bulk-boundary correspondences and even the very concept of a band,pseudo-gaps post profound implications that extend to many-body settings,such as fractional Chern insulators.

关键词： Non-Hermiticity Energy gaps Topological quantum phases Bulk-boundary correspondence

Deconfinement Phase Transition Including Perturbative QCD Corrections in (Proto)neutron Star Matter

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Communications in Theoretical Physics 2008年第2期49卷 461-466页

作者： GU Jian-Fa GUO hua lee Xi-Guo LIU Yu-Xin XU Fu-Rong Department of Technical Physics and MOE Laboratory of Heavy Ion Physics Peking University Beijing 100871 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China Institute of Modern Physics The Chinese Academy of Sciences Lanzhou 730000 China Department of Physics Peking University Beijing 100871 China

Deconlinement phase transition and neutrino trapping in （proto）neutron star matter are investigated in a chiral hadronic model （also referred to as the FST model） for the hadronic phase （HP） and in the color-flavor-locked （CFL） quark model for the deconlined quark phase. We include a perturbative QCD correction parameter αs in the CFL quark matter equation of states. It is shown that the CFL quark core with K^0 condensation forms in neutron star matter with the large value of αs. If the small value of αs is taken, hyperons suppress the CFL quark phase and the liP is dominant in the high-density region of （proto）neutron star matter. Neutrino trapping makes the fraction of the CFL quark matter decrease compared with those without neutrino trapping. Moreover, increasing the QCD correction parameter as or decreasing the bag constant B and the strange quark mass ms can make the fraction of the CFL quark matter increase, simultaneously, the fraction of neutrino in protoneutron star matter increases, too. The maximum masses and the corresponding radii of （proto）neutron stars are not sensitive to the QCD correction parameter αs.

关键词： deconfinement phase transition neutrino trapping neutron star matter

Cdk2 acts upstream of mitochondrial permeability transition during paclitaxel-induced apoptosis

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Protein & Cell 2011年第7期2卷 543-553页

作者： Xiao-Xi Guo Hanna Kim Yang Li Hyungshin Yim Seung Ki lee Ying-hua Jin Key Laboratory for Molecular Enzymology&Engineering of the Ministry of Education Jilin UniversityChangchun 130012China Division of Pharmaceutical Biosciences Research Institute for Pharmaceutical SciencesCollege of PharmacySeoul National UniversitySeoul 151-742Korea

Sequential activation of cyclin-dependent kinases(Cdks)controls mammalian cell *** we demonstrate that the upregulation of cyclin-dependent kinase 2(Cdk2)activity coincides with the loss of mitochondrial membrane potential(MMP)in paclitaxel-induced *** expression of the dominant negative Cdk2(Cdk2-dn)and a specific Cdk2 inhibitor,p21WAF1/CIP1,effectively suppresses the loss of MMP,the release of cytochrome c,and subsequent activation of caspase-3 in paclitaxel-treated *** forced activation of Cdk2 by overexpression of cyclin A dramatically promotes these *** further show that Cdk2 activation status does not interfere with a procedure that lies downstream of cytochrome c release induced by Bax *** findings suggest that Cdk2 kinase can regulate apoptosis at earlier stages than mitochondrial permeability transition and cytochrome c release.

关键词： apoptosis cyclin-dependent kinase 2 cytochrome c release mitochondrial membrane potential paclitaxel

A chromosome-level genome assembly of chia provides insights into high omega-3 content and coat color variation of its seeds

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Plant Communications 2022年第4期3卷 150-160页

作者： Le Wang May lee Fei Sun Zhuojun Song Zituo Yang Gen hua Yue Temasek Life Sciences Laboratory Singapore 117604Singapore Department of Biological Sciences National University of SingaporeSingapore 117543Singapore

Chia(Salvia hispanica)is a functional food crop for *** its seeds contain high omega-3 fatty acids,the seed yield of chia is still *** resources available for this plant are *** report the first high-quality chromosome-level genome sequence of *** assembled genome size was 347.6 Mb and covered 98.1%of the estimated genome size.A total of 31069 protein-coding genes were *** absence of recent whole-genome duplication and the relatively low intensity of transposable element expansion in chia compared to its sister species contribute to its small genome *** sequencing and gene duplication analysis reveal that the expansion of the fab2 gene family is likely to be related to the high content of omega-3 in *** white seed coat color is determined by a single locus on chromosome *** study provides novel insights into the evolution of Salvia species and high omega-3 content,as well as valuable genomic resources for genetic improvement of important commercial traits of chia and its related species.

关键词： genome fatty acid seed coat color Salvia species chia