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Growth of solidified shell in bloom continuous casting mold of hypo-peritectic steel based on a FeS tracer method

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Journal of Iron and Steel Research International 2020年第7期27卷 782-787页

作者： Da-peng Li hua-zhang wu Hai-feng Wang Hong Li State Key Laboratory of Advanced Steel Processing and Products Central Iron and Steel Research InstituteBeijing 100081China Benxi Iron&Steel Group Co. Ltd.Benxi 117021LiaoningChina State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Solidification behavior in the mold region plays an important role in production efficiency and steel *** investigate shell growth within a mold,the sulfur prints of the entire shell thickness profile the meniscus to 100 mm below the mold were obtainedadding FeS tracer into molten steel during bloom continuous casting of hypo-peritectic *** law of shell thickness evolution along mold height and circumference was *** results show that there are three weak regions of solidification,which are in the mold upper part,in the mold lower part,and just below mold exit,possibly resulting periodic fluctuation of air gap between the shell and the mold,the impingement of melt jets on the solidification front,and the decreasing cooling intensity,*** solidification point along casting direction appears at approximately 35 mm below the ***,the solidified shell thickness in the inner side of the mold is a little larger than that in the outer side,and the former and the latter reach 25.5 and 24.3 mm at the mold exit,*** non-uniform shell growth in the inner side of the bloom is provided,while shell thicknesses in the narrow face and the outer side follow relatively regular *** of the mold,the thinnest shells on the transverse section exist in the regions of 60–90 mm and 40–70 mm the corners of the inner and outer sides,respectively,i.e.,the of-corners.

关键词： Continuous casting Mold Hypo-peritectic steel Solidified shell Sulfur print

Incubation and development of corrosion in microstructures of low alloy steels under a thin liquid film of NaCl aqueous solution

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 748-755页

作者： Wen-hua zhang Shan-wu Yang Jia Guo Zhi-yong Liu Xin-lai He School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Electrochemical measurement, optical microscopy, and scanning electron microscopy were employed to investigate the corrosion behavior of some low alloy steels. The steels were held under a thin liquid film of 0.5wt% NaCl aqueous solution. It is found that the steels with the same chemical composition but different micmstructures exhibit obviously different corrosion behaviors. However, the corrosion behavior of the steels with different compositions but the same microstructnres may be similar in the present investigation. The corrosion rate of bainite is slower than that of ferrite and pearlite. The corrosion products of bainite are uniform and fine. The size of carbon-rich phases produces a great impact on the corrosion of the steels, whether in the initial stage or in the long tenn. It is easy to induce large pitting for carbon-rich phases with large size, which damages the compactness of the rust layer.

关键词： alloy steel microstructure atmospheric corrosion liquid films scanning electron microscope

Determination of strychnine and brucine in traditional Chinese medicine preparations by capillary zone electrophoresis with micelle to solvent stacking

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Chinese Chemical Letters 2011年第3期22卷 330-333页

作者： Xiao Fang Yin Zhi Li Shuai hua zhang Chun Xia wu Chun Wang Zhi Wang College of Science Agricultural University of Hebei Baoding 071001 China

A novel micelle to solvent stacking on-line sample preconcentration technique in capillary zone electrophoresis（MSS-CZE） has been developed to determine the strychnine and brucine in traditional Chinese medicine *** optimal running buffer was 30 mmol/L H_3PO_4 containing 20%acetonitrile at pH *** sample matrix was 8 mmol/L H_3PO_4 containing 5 mmol/L sodium dodecyl sulfate（SDS） at pH *** established MSS-CZE method afforded more than 50-fold improvements in concentration sensitivity compared with typical CZE-UV *** calibration curve was linear in the range from 0.2 to 15.0μg/ mL for both strychnine and brucine,with correlation coefficients of 0.9984 and 0.9976,*** limits of detection（5/ N = 3：1） for strychnine and brucine were 0.02 and 0.05μg/mL,*** MSS-CZE method has been successfully applied to the analysis of strychnine and brucine in Chinese medicinal preparations.

关键词： On-line sample preconcentration Micelle to solvent stacking Capillary zone electrophoresis Strychnine Brucine Traditional Chinese medicine preparation

Quantum Theory of Femtosecond Soliton Propagation in Single-Mode Optical Fibers

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Communications in Theoretical Physics 2004年第6期41卷 943-948页

作者： CHEN Shi-hua zhang Shao-wu SHI Du-Fang Department of Physics,huazhong University of Science and Technology,wuhan 430074,China Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

In this paper we have derived the generalized QNLS equation with considering the third-order dispersion andKerr dispersion,which can be applicable to the femtosecond regime and is suitable for discussing the quantum propertiesof femtosecond solitons in single-mode optical fibers,as compared with its classical *** quantum operatorequation can be solved by many methods such as the linearized perturbations and phase-space ***,owingto the fact that this quantum equation is rather similar to its classical counterpart,all these methods can be facilitatedto a great extent by citing correctly the classical results obtained before.

关键词： generalized QNLS equation single-mode-optical fibers third-order dispersion

Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest China

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Pedosphere 2007年第3期17卷 331-342页

作者： SU Yong-Hong FENG Qi ZHU Gao-Feng SI Jian-hua zhang Yan-wu Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou730000 （China） School of Mathematics and Statistics Lanzhou University Lanzhou 730000 （China）

Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids （TDS） in the groundwater showed a great variation, with 62.5% of the samples being brackish （TDS ≥ 1 000 mg L^-l）. The groundwater system showed a gradual hydro-chemical zonation composed of Na^＋ -HCO3^-, Na^＋ -Mg^2＋ -SO4 ^2 -Cl^-, and Na^＋ -Cl^-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and 2- gypsum explained, in part, the presence of Na^＋, K^＋, Cl^-, SO^4 , and Ca^2＋, but other processes, such as mixing, Na^＋ exchange for Ca^2＋ and Mg^2＋, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts.

关键词： Ejin Sub-Basin groundwater quality Heihe River human impact water resources development

Expression of vascular endothelial growth factor and its receptors KDR and Fit-1 in gastric cancer cells

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World Journal of Gastroenterology 2002年第6期8卷 994-998页

作者： hua zhang Jian wu Lin Meng Cheng-Chao Shou,Peking University School ofOncology,Beij ing Institute for Cancer Research,Beijing 100034,China Department of Biochemistry and Molecular Biology Peking University School of Oncology Beijing Institute for Cancer Research China.

AIM: The expression of vascular endothelial growth factor (VEGF) and its receptors KDR and Flt-1 by gastric carcinoma tissues and different gastric carcinoma cell lines was detected to elucidate the molecular mechanism of this growth factor in promoting tumor ***: The expression of VEGF, Flt-1 and KDR was determined by reverse transcription-polymerase chain reaction (RT-PCR) in gastric cancer cell lines RF-1, RF-48,AGS-1, NCI-N87, NCI-SNU-1, NCI-SNU-5, NCI-SNU-16 and KATO-Ⅲ. The expression of Flt-1 and KDR in paraffinembedded specimens of gastric cancer was determined by immunohistochemistry. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess the role of VEGF in tumor cell ***: All 8 gastric cancer cell lines analyzed expressed VEGF121 and VEGF16s and six of them expressed both Flt-1 and KDR, while cell line NCI-SNU-5 expressed Flt-1 only and cell line KATOⅢ expressed neither Flt-1 nor KDR. The gastric carcinoma tissues expressed Flt-1 and KDR widely,with the positive rate of expression of Flt-1 and KDR being 84.6 % and 70 % respectively. The exogenous VEGF stimulated the growth of KDR-positive cell lines NCI-N87 and AGS-1 in a dose-dependent manner but exhibited no effect on the growth of KDR-negative cell line ***: VEGF and its receptors KDR and Flt-1 were expressed widely in gastric carcinoma cells and the VEGF stimulated KDR-positive tumor cell growth directly. These results suggest that VEGF may play a role in promoting tumor growth and metastasis by participating in both paracrine and autocrine pathways.

关键词：血管内皮生长因子 VEGF受体 KDR Flt-1 胃癌细胞基因表达

STUDIES ON THE PRENYLFLAVONOIDS PART *** OF(±)LESPEDEZAFLAVANONE D

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Chinese Chemical Letters 1993年第4期4卷 283-284页

作者： Fang Jie zhang hua wu SHAO Yu Lin LI Satate key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou 730000

(±)Lespedezaflavanone D,8,5'-di(γ,γ-dimethylallyl)-5,7,2',4'-tetrahydroxyflavanone,has been synthesized by the condensation of 4,6-dimethoxymethoxy-3-(γ,γ-dimethylallyl)-2-hydroxy- acetophenone with 2,4-dimethoxy... 详细信息

关键词： LESPEDEZAFLAVANONE D STUDIES ON THE PRENYLFLAVONOIDS PART V.SYNTHESIS OF ppm Wang FAB

Advancements and Challenges in Organic–Inorganic Composite Solid Electrolytes for All‑Solid‑State Lithium Batteries

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Nano-Micro Letters 2025年第1期17卷 46-97页

作者： Xueyan zhang Shichao Cheng Chuankai Fu Geping Yin Liguang Wang Yongmin wu hua Huo State Key Laboratory of Space Power‑Sources School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001People’s Republic of China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310058People’s Republic of China State Key Laboratory of Space Power-Sources 2965 Dongchuan RoadMinhang DistrictShanghai 200240People’s Republic of China

To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified as an up-and-coming *** the various SEs,organic–inorganic composite solid electrolytes(OICSEs)that combine the advantages of both polymer and inorganic materials demonstrate promising potential for large-scale ***,OICSEs still face many challenges in practical applications,such as low ionic conductivity and poor interfacial stability,which severely limit their *** review provides a comprehensive overview of recent research advancements in ***,the influence of inorganic fillers on the main functional parameters of OICSEs,including ionic conductivity,Li+transfer number,mechanical strength,electrochemical stability,electronic conductivity,and thermal stability are systematically *** lithium-ion conduction mechanism of OICSE is thoroughly analyzed and concluded from the microscopic ***,the classic inorganic filler types,including both inert and active fillers,are categorized with special emphasis on the relationship between inorganic filler structure design and the electrochemical performance of ***,the advanced characterization techniques relevant to OICSEs are summarized,and the challenges and perspectives on the future development of OICSEs are also highlighted for constructing superior ASSLBs.

关键词： Composite solid electrolytes Inorganic filler Interfacial stability Li-ion conduction mechanism Characterization techniques

STUDIES ON THE PRENYLFLAVONOIDS PARTⅡ.SYNTHESIS OF EUCHRENONE A_7

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Chinese Chemical Letters 1992年第1期3卷 3-4页

作者： Yu Lin LI Fang Jie zhang hua wu ShAO Shao Bai LI State Key Laboratory of Applied Organic Chemistry,Lanzhou University,Lanzhou 730000

Euchrcnonc a_7 has been prcparcd by condensation of 2-hydroxy-4- mcthoxy-3-prcnylacctophcnone with 2,4-dimethoxymethoxybenzaldehyde followed by cyclization and demethoxymethylation.

关键词： ppm OCH STUDIES ON THE PRENYLFLAVONOIDS PART SYNTHESIS OF EUCHRENONE A7