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Journal of Iron and Steel Research International 2024年第8期31卷 1923-1935页

作者： Yu Zhao Cheng-bin shi shijun wang Peng Ren Jing Li State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing(USTB)Beijing 100083China

The evolution of Ce-containing inclusions and its correlation with the reoxidation of liquid steel during protective atmosphere electroslag remelting(ESR)of heat-resistant steel were *** reoxidation of liquid steel took place during the ESR,resulting in the oxygen pickup from 0.0014 to 0.0053 wt.%.The inclusions in the consumable electrode,liquid metal pool and remelted ingot are Ce_(2)O_(2)S and Ce_(2)O,inclusions *** inclusions in the remelted ingot are originated from three ways:(I)the original inclusions from the electrode;(Il)the newly formed Ce_(2)O_(2)S and Ce_(2)O_(3) inclusions in the liquid metal pool by reoxidation remaining still in remelted ingot;(IlI)the newly generated Ce2O2S and Ce_(2)O_(3) inclusions during cooling and solidification of liquid *** relative proportions of Ce_(2)O_(3) inclusions in liquid metal pool and remelted ingot are 41% and 76.5%,*** inclusions ranging from 2 to 5μm in the remelted ingot take up 55%,followed by the inclusions smaller than 2μm(43%of total inclusions).The number proportion of the Ce_(2)0,inclusions in the liquid metal pool which were removed by floating up into slag is 1.96×10-5%.

关键词： Non-metallic inclusion Electroslag remelting Rare earth cerium Reoxidation Inclusion evolution

Non-metallic inclusions in electroslag remelting:a review

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Journal of Iron and Steel Research International 2021年第12期28卷 1483-1503页

作者： Cheng-bin shi shi-jun wang Jing Li jung-wook Cho Institute of Advanced Steel State Key Laboratory of Advanced MetallurgyUniversity of Science and Technology Beijing(USTB)Beijing100083China Graduate Institute of Ferrous and Energy Materials Technology Pohang University of Science and Technology(POSTECH)Pohang790-784Republic of Korea

Non-metallic inclusion in electroslag remelting is a constant topic that has been studied for *** results and conclusions are obtained on some of the subjects from these previous *** differences originate in part from different experimental conditions,including original inclusion chemistries in consumable electrode,slag composition,oxygen level,liquid metal compositions,deoxidation schemes,and melting rates of electroslag *** advances in the operating practices of inclusion control in electroslag remelting production are *** evolution during the electroslag remelting and related processing parameters are also reviewed and *** role of the reoxidation of liquid steel during electroslag remelting on oxide inclusion composition is *** generation of inclusions in remelted ingot is critically *** and remaining issues are noted.

关键词： Non-metallic inclusion Electroslag remelting Inclusion removal Reoxidation

Eutectic precipitates and microstructure of electroslag remelted 15Cr-22Ni austenitic heat-resistant steel with varying Nb contents

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Journal of Iron and Steel Research International 2022年第11期29卷 1823-1835页

作者： Hao-chi Xu Cheng-bin shi Xin Zhu shi-jun wang Jing Li shi-zhou wang State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing(USTB)Beijing 100083China

The microstructure,eutectic carbides and intermetallic compounds in as-cast ingots with varying Nb contents produced by electroslag remelting were *** solidification behavior,microsegregation of alloying elements and its influence on precipitates were *** increase in Nb content from 0.64 to 1.40 wt.%has no effect on the dendrite morphology and secondary dendrite arm *** total area fraction of eutectic NbC and Laves phase in as-cast ingots increases with the increase in Nb *** eutectic precipitates in the ingot with 0.64 wt.%Nb are mainly NbC,and the others are Fe_(2)Nb-type Laves *** the Nb content of the steel significantly promotes the precipitation of Laves phases and lowers the precipitation temperature of NbC eutectic *** carbide M_(2)C is precipitated only in the ingot with 1.4 wt.%*** average concentration of Nb in both interdendritic and intragranular regions increases with the increase in Nb content of the steel,leading to a change in the morphology of Fe_(2)Nb-type Laves phase from honeycomb to *** the Nb content exerts little effect on the microsegregation degrees of Si,Mo,Cr and Ni in the steel.

关键词： Eutectic carbides Fe2Nb-type Laves phase Austenitic heat-resistant steel Microsegregation Electroslag remelting

Review on Fault-Tolerant NoC Designs

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Journal of Electronic Science and Technology 2018年第3期16卷 191-221页

作者： jun-shi wang Le-Tian Huang the School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731 Beijing Zhaoxin Electronic Technology Co. Ltd.Beijing 100084 the School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054

By benefiting from the development of the semiconductor technology, many-core system-on-chips(SoCs)have been widely used in electronic devices. Network-on-chips(NoCs) can address the massive stress of on-chip communications due to the advantages of high bandwidth, low latency, and good flexibility. Since deep sub-micron era, the reliability has become a critical constraint for integrated circuits. To provide correct data transmission, faulttolerant NoCs have been researched widely in last decades, and many valuable designs have been proposed. This work introduces and summarizes the state-of-the-art technologies for fault diagnosis and fault recovery in faulttolerant NoCs. Moreover, this work makes prospects for the future’s research.

关键词： Fault diagnosis fault recovery fault-tolerant network-on-chip

Effect of cerium on microstructure,eutectic carbides and Laves phase in electroslag remelted 15Cr-22Ni-1Nb austenitic heat-resistant steel

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Journal of Iron and Steel Research International 2023年第2期30卷 338-349页

作者： Xin Zhu Cheng-bin shi shi-jun wang Peng Lan Jing Li State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing(USTB)Beijing100083China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China

The dendrites,eutectic carbides,Laves phase and microsegregation of alloying element in electroslag remelted 15Cr-22Ni-1Nb austenitic heat-resistant steel with varying cerium contents were *** liquidus and solidus temperatures of the steel were determined to reveal the effect of cerium on solidification temperature interval and local solidification time of the *** secondary dendrite arm spacing decreases from 57.10 to 40.18μm with increasing the cerium content from 0 to 0.0630 wt.%.The eutectic NbC and Laves phase in as-cast ingots exhibit blocky and honeycomb morphology,*** area fractions and sizes of eutectic NbC and Laves phase in as-cast ingots decrease with the increase in cerium *** atomic percentage of Laves phase-forming element(Ni,Nb,Cr,Mo and Si)decreases with the increase in cerium content of the *** microsegregation of Mo,Ni,Si,Cr and Nb decreases with increasing the cerium content,which is favorable to reducing both the amount and sizes of eutectic NbC and Laves phase in as-cast *** solidification temperature interval and local solidification time of the steel decrease as the cerium content is increased from 0 to 0.0630 wt.%,which inhibits the growth of dendrites,eutectic NbC and Laves phase.

关键词： Heat-resistant steel Rare earth cerium Eutectic NbC Laves phase Microsegregation Solidification characteristics

New Species of the Isolated Psaroniaceous Rachis from the Early Permian in China

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Journal of Integrative Plant Biology 2008年第1期50卷 119-127页

作者： Ning Xiang shi-Min Ma Bao-Lin Tian shi-jun wang Ming-Shan Zhang State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China China University of Mining and Technology Beijing 100083 China 107th Team Northeast Coal Geology Bureau Fuxin 123000 China

A new kind of marattialean raches are reported from the coal balls in Coal Seam No.7 in the upper part of the Taiyuan Formation （early Early Permian） from Taiyuan, Shanxi, China and are assigned to the genus Stipitopteris Grand＇Eury （Psaroniaceae）. The present specimens are different from all six reported species of the genus, and are therefore proposed as a new species： Stipitopteris shanxiensis. The raches of the new species are generally dorsi-ventrally flattened. The main raches usually exhibit scales of different forms on their surface. Beneath the epidermis is a zone of parenchymatous cells, some of which contain tannin-like contents. Inside this is a zone of small sclerenchymatous cells. Inward are the ground tissue and vascular bundles. The vascular bundles are continuous and are in two circles： the outer circle assumes a transversely elliptical shape with the gap and pinna trace, and the inner circle assumes a shallow *** with inrolled ends. The ground tissue located at the inner side of the vascular bundle is composed of thicker-walled parenchymatous cells. The cells of the ground tissue are vertically elongated in longitudinal sections. Subordered raches are smaller and have simpler structures than the main raches. The parenchyma zone beneath the epidermis is thinner, usually one to two cells wide and the sclerenchyma zone is usually absent. The scales are poorly developed and there is only one C-shaped vascular bundle. The new species is comparable to the crosiers of Psaroniaceae of the Euramerican Flora in some aspects, for example, it has a dorsi-ventrally flattened rachis and scales on the surface of the rachis. However, the other features and the preservative conditions of the present specimens indicate that they are not crosiers, but fully developed or mature raches. The new species is the first well-studied anatomically-preserved rachis of Psaroniaceae from the Cathaysian Flora and bears significance not only in understanding the anatomy and ta

关键词： coal ball Early Permian new species Psaroniaceae rachis Stipitopteris.

Greedy is Good:Constrained Non-submodular Function Maximization via Weak Submodularity

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Journal of the Operations Research Society of China 2024年第3期12卷 627-648页

作者： Ma-jun shi Wei wang School of Statistics Xi’an University of Finance and EconomicsXi’an710100ShaanxiChina School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

The widely used greedy algorithm has been recently shown to achieve near-optimal theoretical guarantees for the problems of constrained monotone non-submodular function maximization,with competitive performances in *** this paper,we investigate the problems of maximizing monotone non-submodular set functions under three classes of independent system constraints,including p-matroid intersection constraints,p-extendible system constraints and p-system *** prove that the greedy algorithm yields an approximation ratio ofγ/p+γfor the former two problems,andξγ/p+ξγfor the last problem,which further has been improved toγ/p+γ,whereγ,ξdenote the submodularity ratio and the diminishing returns ratio of set function *** addition,we also show that the greedy guarantees have a further refinement of for all the problems mentioned above,whereαis the generalized curvatureξ/p+αγof set ***,we show that our greedy algorithm does yield competitive practical performances using a variety of experiments on synthetic data.

关键词： Non-submodular function p-matroid intersection p-extendible system p-system Greedy algorithm

CONDITIONAL AVERAGING OF TR-PIV MEASUREMENTS OF WAKE BEHIND SQUARE CYLINDER USING AN IMPROVED CROSS-CORRELATION APPROACH

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Journal of Hydrodynamics 2010年第1期22卷 29-34页

作者： YU jun shi Liu-liu wang Wei-zhe LIU Ying-zheng Key Laboratory for Power Machinery and Engineering of Ministry of Education Shanghai Jiao Tong University Shanghai 200240 China

An improved phase averaging method based on cross-correlation of the instantaneous velocity field determined by TR-PIV measurements is proposed in this article. A Time-Resolved Particle Image Velocimetry （TR-PIV） is used to measure the two-dimensional wake behind the square cylinder. The phase signals associated with the deterministic appearance of the Karman vortex street are obtained by calculating the correlation matrix of the low-pass filtered velocity field, and can provide the complete information of the phase-averaged wake flow. The results show the advantages of the enhanced methodology in extracting the quasi-periodic flow patterns related to the shedding coherent structures without using additional reference signals.

关键词： PIV cross-correlation coherent structure phase averaging

Electrochemistry and In-situ Spectroelectrochemistry Studies of Carbazole and 9-Ethylcarbazole

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Chinese Chemical Letters 2005年第12期16卷 1621-1624页

作者： Zi Pin ZHANG Bao Kang JIN Yu Peng TIAN shi jun wang School of Chemistry and Chemical Engineering Anhui University Hefei 230039

Mechanisms of electron transfer of carbazole （CZ） and 9-ethylcarbazole （ECZ） were studied by electrochemistry and in-situ spectroelectrochemistry. The result indicated that the electrochemical reaction mechanism of ECZ was the same as that of CZ. Both of them undergo ECE process： the initial step is removal of one electron to generate very reactive cation radical, this species then proceeded by deprotonation-coupling reaction to form the corresponding dimer, which was oxidized continuously.

关键词： Carbazole in-situ spectroelectrochemistry cation radical

Radiological and clinical outcomes of midline lumbar fusion on sagittal lumbar-pelvic parameters for degenerative lumbar diseases

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World Journal of Clinical Cases 2022年第35期10卷 12880-12889页

作者： Yue-Tian wang Bing-Xu Li shi-jun wang Chun-De Li Hao-Lin Sun Department of Orthopedics Peking University First HospitalBeijing 100034China

BACKGROUND Improving the sagittal lumbar-pelvic parameters after fusion surgery is important for improving clinical *** impact of midline lumbar fusion(MIDLF)on sagittal lumbar-pelvic alignment for the management of degenerative lumbar diseases is still *** To analyze the effects of short-segment MIDLF and minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF)on sagittal lumbar-pelvic *** We retrospectively analyzed 63 patients with degenerative lumbar diseases who underwent single-segment MIDLF or *** imaging data of patients were collected before surgery and at the final *** radiological sagittal parameters included the lumbar lordosis(LL),lower LL,L4 slope(L4S),L5 slope(L5S),L5 incidence(L5I),L1 axis and S1 distance(LASD),pelvic incidence(PI),pelvic tilt(PT),sacral slope(SS),and PI-LL mismatch(PI-LL).Additionally,the clinical outcomes,including lower back and leg pain visual analog scale(VAS)and Oswestry disability index(ODI)scores,were also *** In both groups,LL and Lower LL significantly increased,while L5I and LASD significantly decreased at the final follow-up compared to that recorded prior to operation(P0.05).However,the PI-LL in both groups was significantly reduced compared to that recorded prior to operation(P0.05).In addition,the change in sagittal lumbar-pelvic parameters did not differ significantly,except forΔLASD withi

关键词： Minimally invasive Interbody fusion Cortical bone trajectory Sagittal lumbar-pelvic parameters