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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1489-1498页

作者： Xiao-qian Pan jian Yang Joohyun Park Hideki Ono State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Department of Materials Engineering Hanyang UniversityAnsan 426-791South Korea Faculty of Sustainable Design University of ToyamaToyama-ken 930-8555Japan

The specific distribution characteristics of inclusions along with the sliver defect were analyzed in detail to explain the formation mechanism of the sliver defect on the automobile exposed panel surface.A quantitative electrolysis method was used to compare and evaluate the three-dimensional morphology,size,composition,quantity,and distribution of inclusions in the defect and non-defect zone of automobile exposed *** Al2O3 inclusions were observed to be aggregated or chain-like shape along with the sliver defect of about 3–10μ*** aggregation sections of the Al2O3 inclusions are distributed discretely along the rolling direction,with a spacing of 3–7 mm,a length of 6–7 mm,and a width of about 3 *** inclusion area part is 0.04%–0.16%with an average value of 0.08%,the inclusion number density is 40 mm−2 and the inclusion average spacing is 25.13μ*** inclusion spacing is approximately 40–160μm,with an average value of 68.76μm in chain-like inclusion *** average area fraction and number density of inclusions in the non-defect region were reduced to about 0.002%and 1–2 mm^−2,respectively,with the inclusion spacing of 400μm and the size of Al2O3 being 1–3μm.

关键词： automobile exposed panel sliver defect quantitative electrolysis three-dimensional inclusions aggregated inclusions chain-like inclusions

Effect of MgO on structure and crystallization behavior of CaO–SiO_(2)–Al_(2)O_(3) inclusions in Si–Mn deoxidized steel

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Journal of Iron and Steel Research International 2024年第11期31卷 2774-2787页

作者： Qi Xu Yao-qing Meng jian-li Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina

To avoid coarse crystallization of glassy inclusions in Si–Mn deoxidized steel during hot rolling, the effect of MgO on the structure and crystallization behavior of CaO–SiO_(2)–Al_(2)O_(3) inclusions was investigated. The results showed that the crystallization temperature of the oxide melts decreased with increasing MgO content from 0 to 15.7 wt.%, which suggested that the addition of MgO would increase the temperature range of the crystalline transition. The increase in MgO content could decrease the crystallization activation energy of inclusions. With the increase in MgO content, the relative fractions of O_(Si)^(0) and O_(Si)^(1) structure units increased, and those of structure units O_(Si)^(2), O_(Si)^(3), and O_(Si)^(4) decreased, increasing the depolymerization degree of the silicate structure. The crystallization ratio of glassy inclusions in the steel crucible increased from 19.7% to 98.3% with increasing MgO content from 0 to 15.7 wt.%. The addition of MgO improved the crystallization ability of inclusions, because MgO provides free oxygen O_(2−) to destroy the bridging oxygens and form non-bridging oxygens O^(−), which depolymerizes silicate network structure and simplifies the [SiO_(4)]-tetrahedral structure. In addition, MgO would promote the precipitation of the Mg-containing phases with a high melting point. When the MgO content was increased above 12.1 wt.%, MgO·Al_(2)O_(3) and 2MgO·SiO_(2) crystalline phases would precipitate from the inclusions.

关键词： Si-Mn deoxidized steel Glassy inclusion Structure Crystallization Plasticization

Plasticity Induced by Twin Lamellar Structure in Magnesium Alloy

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Journal of Materials Science & Technology 2013年第12期29卷 1123-1128页

作者： Xiyan Zhang Chao Lou jian Tu qing Liu School of Materials Science and Engineering Chongqing University

Effect of {10-12} twins on the mechanical properties of magnesium alloy has received considerable research interest. A hot-rolled AZ31 Mg alloy sheet was subjected to dynamic plastic deformation with the aim of introducing {10-12} twin lamellar structure. It has been found that higher strength and better ductility are obtained when tensile loading is perpendicular to the c axis of twin region of the twin lamellar structured sample, indicating that the plasticity improvement caused by twins depends on the special strain path. The fracture morphology of the twin lamellar structured sample shows a dimple fracture mode under tensile loading perpendicular to the c axis, while the cleavage fracture with river pattern has been observed in other fractured samples. Above experimental results indicate that the interaction of dislocations and twin lamellae may play an important role in improving mechanical properties of Mg alloy.

关键词： Magnesium alloy Twin lameilar structure Mechanical behavior Plasticity

Experimental Study on Combustion Characteristics and NOX Emissions of Pulverized Anthracite Preheated by Circulating Fluidized Bed

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Journal of Thermal Science 2011年第4期20卷 355-361页

作者： WANG Jun ZHU jian-guo LU qing-gang Institute of Engineering Thermophysics Chinese Academy of Sciences 11 Beisihuanxi Road Haidian District Beijing 100190 China Graduated University of Chinese Academy of Sciences Shijingshan District Beijing 100049 China

A 30 kW bench-scale rig of pulverized anthracite combustion preheated by a circulating fluidized bed （CFB） was developed. The CFB riser has a diameter of 90 mm and a height of 1,500 mm. The down-fired combustion chamber （DFCC） has a diameter of 260 mm and a height of 3,000 mm. Combustion experiments were carded out using pulverized anthracite with 6.74% volatile content. This low volatile coal is difficult to ignite and burn out. Therefore, it requires longer burnout time and higher combustion temperature, which results in larger NOx emis- sions. In the current study, important factors that influence the combustion characteristics and NOx emissions were investigated such as excess air ratio, air ratio in the reducing zone, and fuel residence time in the reducing zone. Pulverized anthracite can be quickly preheated up to 800~C in CFB when the primary air is 24% of theo- retical air for combustion, and the temperature profile is uniform in DFCC. The combustion efficiency is 94.2%, which is competitive with other anthracite combustion technologies. When the excess air ratio ranges from 1.26 to 1.67, the coal-N conversion ratio is less than 32% and the NOx emission concentration is less than 371 mg/m^3 （@6% O2）. When the air ratio in the reducing zone is 0.12, the NOx concentration is 221 mg/m^3 （@6% O2）, and the coal-N conversion ratio is 21%, which is much lower than that of other boilers.

关键词： circulating fluidized bed preheat pulverized anthracite NOx

Double-balloon enteroscopy reliably directs surgical intervention for patients with small intestinal bleeding

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World Journal of Gastroenterology 2008年第12期14卷 1936-1940页

作者： Mou-Bin Lin Lu Yin jian-Wen Li Wei-Guo Hu qian-jian qian Department of Surgery Ruijin Hospital Shanghai 200025China

AIM: To evaluate preoperative double-balloon enteroscopy for determining bleeding lesions of small intestine, thus directing selective surgical intervention. METHODS: We retrospectively reviewed 56 patients who underwent double-balloon enteroscopy to localize intestinal bleeding prior to surgical intervention, and compared enteroscopic findings with those of intraoperation to determine the accuracy of enteroscopy in identifying and localizing the sites of small intestinal bleeding. RESULTS: Double-balloon enteroscopy was performed in all 56 patients in a 30-mo period. A possible site of blood loss was identified in 54 (96%) patients. Enteroscopy provided accurate localization of the bleeding in 53 (95%) of 56 patients, but failed to disclose the cause of bleeding in 4 (7%). There was one case with negative intraoperative finding (2%). Resection of the affected bowel was carried out except one patient who experienced rebleeding after operation. Gastrointestinal stromal tumor (GIST) was most frequently diagnosed (55%). CONCLUSION: Double-balloon enteroscopy is a safe, reliable modality for determining bleeding lesion of small intestine. This technique can be used to direct selective surgical intervention.

关键词： Double-balloon enteroscopy Small intestinebleeding Surgery

Constacyclic and cyclic codes over finite chain rings

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 122-125页

作者： qian jian-fa MA Wen-ping National Key Laboratory of ISN Xidian University Xi' an 710071 China

The problem of Gray image of constacyclic code over finite chain ring is studied. A Gray map between codes over a finite chain ring and a finite field is defined. The Gray image of a linear constacyclic code over the finite chain ring is proved to be a distance invariant quasi-cyclic code over the finite field. It is shown that every code over the finite field, which is the Gray image of a cyclic code over the finite chain ring, is equivalent to a quasi-cyclic code.

关键词： constacyclic code Gray map quasi-cyclic code cyclic code

One-dimensional(1D) micro/nanostructures of organic semiconductors for field-effect transistors

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Science China Chemistry 2015年第6期58卷 937-946页

作者： Yu-qing Zheng Jie-Yu Wang jian Pei Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University

Organic semiconductors have gradually become the super stars on the stage of optoelectronic materials, due to their low cost, flexibility and solution processability. Numerous organic semiconductors, including small molecules and conjugated polymers, have been designed and synthesized to explore the potential of organic materials in optoelectronic industry. One-dimensional micro/nanostructures of organic semiconductors generally have more ordered packing structure with fewer defects compared with thin films, and are thus thought to show intrinsic carrier mobility of organic materials. Moreover, the packing structure in micro/nanostructures is clear and relatively easy to analyze, which makes these micro/nanostructures a good platform to study structure-property relationship. Therefore, design of suitable organic molecules to form micro-/nanostructures and methods to obtain ideal micro/nanostructures for functional devices will be fully discussed in this mini review. Finally, the perspective and opportunity of 1D micro/nanostructured organic materials based OFETs in the near future are also addressed.

关键词： organic semiconductors organic field-effect transistors one-dimensional micro/nanostructures self-assembly

Can a sneeze after phacoemulsification cause endophthalmitis? A case report

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International Journal of Ophthalmology(English edition) 2022年第5期15卷 841-844页

作者： Yi-Wen qian qing-jian Li Xin Che Jing jiang Zhi-Liang Wang Department of Ophthalmology Huashan Hospital of Fudan UniversityShanghaiChina

Dear Editor, We reported the first case of acute exogenous postoperative endophthalmitis caused by a normal human microbiota in the nasopharynx, Streptococcus anginosus. The patient had a successful cataract surgery, ... 详细信息

关键词： surgery acute endophthalmitis

Selective reduction of carbon dioxide into amorphous carbon over activated natural magnetite

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 231-237页

作者： Zhong-qing Liu jian Zheng Yi Wang Xu Liu School of Chemical Engineering Sichuan UniversityChengdu 610065China

Natural magnetite formed by the isomorphism substitutions of transition metals,including Fe,Ti,Co,etc.,was activated by mechanical grinding followed by H2 *** temperature-programmed reduction of hydrogen(H2-TPR)and temperature-programmed surface reaction of carbon dioxide(CO2-TPSR)were carried out to investigate the processes of oxygen loss and CO2 *** samples were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM),and energy-dispersive X-ray spectroscopy(EDS).The results showed that the stability of spinel phases and oxygen-deficient degree significantly increased after natural magnetite was mechanically milled and reduced in H2 ***,the activity and selectivity of CO2 reduction into carbon were *** deposited carbon on the activated natural magnetite was confirmed as *** amount of carbon after CO2 reduction at 300°C for 90 min over the activated natural magnetite was 2.87wt%higher than that over the natural magnetite.

关键词： carbon dioxide reduction natural magnetite isomorphism substitutions grind activation oxygen-deficient degree amorphous carbon

HeteroMeth： A Database of Cell-to-cell Heterogeneity in DNA Methylation

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Genomics, Proteomics & Bioinformatics 2018年第4期16卷 234-243页

作者： qing Huan Yuliang Zhang Shaohuan Wu Wenfeng qian State Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China Key Laboratory of Genetic Network Biology Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

DNA methylation is an important epigenetic mark that plays a vital role in gene expression and cell differentiation. The average DNA methylation level among a group of cells has been extensively documented. However, the cell-to-cell heterogeneity in DNA methylation, which reflects the differentiation of epigenetic status among cells, remains less investigated. Here we established a gold standard of the cell-to-cell heterogeneity in DNA methylation based on single-cell bisulfite sequencing （BS-seq） data. With that, we optimized a computational pipeline for estimating the heterogeneity in DNA methylation from bulk BS-seq data. We further built HeteroMeth, a database for searching, browsing, visualizing, and downloading the data for heterogeneity in DNA methylation for a total of 141 samples in humans, mice, Arabidopsis, and rice. Three genes are used as examples to illustrate the power of HeteroMeth in the identification of unique features in DNA methylation. The optimization of the computational strategy and the construction of the database in this study complement the recent experimental attempts on single-cell DNA methylomes and will facilitate the understanding of epigenetic mechanisms underlying cell differentiation and embryonic development. HeteroMeth is publicly available at http：//***/HeteroMeth.

关键词： Cell-to-cell heterogeneity DNA methylation Bisulfite sequencing Single cell Shannon entropy