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Journal of Iron and Steel Research International 2024年第9期31卷 2156-2172页

作者： jian-fa Jing Shuai Wang Yu-feng Guo feng Chen Ling-zhi yang jian-feng yang Fu-chun Xu School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina

To optimize the comprehensive utilization of vanadium titanomagnetite by direct reduction-smelting processes,it is essential to acquire titanium slag with a higher TiO_(2)content of 45–60 wt.%.A thermodynamic model was developed based on the ion and molecule coexistence theory,specifically targeting the CaO–SiO_(2)–Al_(2)O_(3)–MgO–TiO_(2)–V_(2)O_(3)–FeO slag *** impact of slag composition on the smelting of vanadium titanomagnetite was assessed,and the thermodynamic model was utilized to identify the optimal high-titanium *** results revealed that increasing the basicity,MgO content,and FeO content within the slag effectively suppressed the reduction of titanium and silicon ***,the calculated activity coefficient of TiO_(2)decreased with higher basicity,MgO,and FeO *** an increase in basicity significantly enhanced the reduction of vanadium oxides,the effects of MgO and FeO contents on vanadium oxide reduction were comparatively less ***,higher basicity and FeO content promoted the formation of calcium titanates,whereas an elevated MgO content favored the formation of magnesium *** smelting results indicated that a lower V_(2)O_(3)content and higher TiO_(2)activity corresponded to a smaller titanium mass fraction in the iron alloy,while the opposite trend was observed for vanadium.

关键词： Vanadium titanomagnetite Titanium slag Vanadium Ion and molecule coexistence theory

Syntheses and Crystal Structures of Co(Ⅱ)Complexes with 5-Tert-butyl Isophthalic Acid

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1108-1114页

作者： QIN jian-Hua JU feng-yang College of Chemistry and Chemical Engineering Luoyang Normal University Luoyang 471022 China

Two new Co（ Ⅱ） coordination polymers {[Co（Htbip）2（H2O）4]·（H2O）}n 1 and {[Co2（tbip）2Copa）1.5]（H2tbip）}n 2 （H2tbip = 5-tert-butyl isophtha]ic acid, bpa = 1,2-dis（4-pyri- dyl）ethane） have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy and X-ray diffraction. Compound 1 exhibits a water-bridged 1-D linear chain which is extended by hydrogen bonds into a 3D supramolecular network, while compound 2 has a dinuclear unit extended by bpa ligand to form a 2-D layer.

关键词： Co(Ⅱ) complex 5-tert-butyl isophthalic acid crystal structure

Improved performances of lithium disilicate glass-ceramics by seed induced crystallization

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Journal of Advanced Ceramics 2021年第3期10卷 614-626页

作者： Ting ZHAO Mei-Mei LIAN Yi QIN jian-feng ZHU Xin-Gang KONG jian-feng yang School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

Self-reinforced lithium disilicate(Li_(2)Si_(2)O_(5),LD)glass-ceramics were hot pressing sintered by introducing 5 wt%Li_(2)Si_(2)O_(5)crystal seeds into two different glass compositions of SiO_(2)-Li_(2)O-P2O_(5)-ZrO_(2)-Al_(2)O_(3)-K_(2)O-La_(2)O_(3)(7C LD)and SiO_(2)-Li_(2)O-K_(2)O-La_(2)O_(3)(4C LD).The results show that the seeds play an important role in the crystallization inducement,and microstructural and property improvement of the glass,especially for the glass powder without the nucleating agent of P_(2)O_(5).The microstructure features a wider bimodal grain size distribution with large rod-like crystals epitaxially grown along the seeds and small crystals nucleated from the glass powder itself,contributing to the improvement of the performance especially the fracture *** specimen of 4C LD glass with the addition of 5 wt%Li_(2)Si_(2)O_(5) seeds exhibited the best comprehensive properties with a good flexural strength(396±7 MPa),improved fracture toughness(3.31±0.19 MPa·m^(1/2)),and comparable translucency as IPS *** research provides a new idea and method for the improvement of the fracture toughness of lithium disilicate glass-ceramics without affecting its aesthetic appearance,and lays the foundation for its clinical applications.

关键词： lithium disilicate(LD) seeds mechanical properties translucency

Column-orthogonal designs with multi-dimensional stratifications

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Science China Mathematics 2021年第6期64卷 1291-1304页

作者： Xue yang jian-feng yang Min-Qian Liu Qi Zhou School of Statistics Tianjin University of Finance and EconomicsTianjin 300222China School of Statistics and Data Science LPMC&KLMDASRNankai UniversityTianjin 300071China

The orthogonal Latin hypercube design and its relaxation,and column-orthogonal design,are two kinds of orthogonal designs for computer ***,they usually do not achieve maximum stratifications in multi-dimensional *** this paper,we propose some methods to construct column-orthogonal designs with multi-dimensional stratifications by rotating symmetric and asymmetric orthogonal *** newly constructed column-orthogonal designs ensure that the estimates of all linear effects are uncorrelated with each other and even uncorrelated with the estimates of all second-order effects(quadratic effects and bilinear effects)when the rotated orthogonal arrays have strength larger than *** orthogonality,the resulting designs also preserve better space-filling properties than those constructed by using the existing *** addition,we provide a method to construct a new class of orthogonal Latin hypercube designs with multi-dimensional stratifications by rotating regular factorial *** newly constructed orthogonal Latin hypercube designs are tabulated for practical use.

关键词： computer experiment Latin hypercube design orthogonal array orthogonality rotation matrix

Microstructure and mechanical properties of reaction-bonded B_(4)C–SiC composites

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International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1828-1835页

作者： Rong-zhen Liu Wen-wei Gu Yu yang Yuan Lu Hong-bin Tan jian-feng yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Material Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Environment-Friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang 621010China

Reaction-bonded B_(4)C–SiC composites are highly promising materials for numerous advanced technological ***,their microstructure evolution mechanism remains ***,B_(4)C–SiC composites were fabricated through the Si-melt infiltration *** influences of the sintering time and the B_(4)C content on the mechanical properties,microstructure,and phase evolution were investigated.X-ray diffraction results showed the presence of SiC,boron silicon,boron silicon carbide,and boron *** electron microscopy results showed that with the increase in the boron carbide content,the Si content decreased and the unreacted B_(4)C amount increased when the sintering temperature reached 1650°C and the sintering time reached 1 *** unreacted B_(4)C diminished with increasing sintering time and temperature when B_(4)C content was lower than 35wt%.Further microstructure analysis showed a transition area between B_(4)C and Si,with the C content marginally higher than in the Si *** indicates that after the silicon infiltration,the diffusion mechanism was the primary sintering mechanism of the *** the diffusion process progressed,the hardness *** maximum values of the Vickers hardness,flexural strength,and fracture toughness of the reaction-bonded B_(4)C–SiC ceramic composite with 12wt%B_(4)C content sintered at 1600°C for 0.5 h were about HV 2400,330 MPa,and 5.2 MPa·m^(0.5),respectively.

关键词： reaction sintering B_(4)C-SiC composites mechanical properties microstructural characterization microstructure evolution mechanism

Rare variant of pancreaticobiliary maljunction associated with pancreas divisum in a child diagnosed and treated by endoscopic retrograde cholangiopancreatography: A case report

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World Journal of Clinical Cases 2019年第9期7卷 1073-1079页

作者： Guang-Xing Cui Hai-Tao Huang jian-feng yang Xiao-feng Zhang Department of Gastroenterology Affiliated Hangzhou First People’s Hospital Zhejiang University School of Medicine

BACKGROUND Pancreaticobiliary maljunction(PBM) is an uncommon congenital anomaly of the pancreatic and biliary ductal system, defined as a union of the pancreatic and biliary ducts located outside the duodenal wall. According to the Komi classification of PBM, the common bile duct(CBD) directly fuses with the ventral pancreatic duct in all types. Pancreas divisum(PD) occurs when the ventral and dorsal ducts of the embryonic pancreas fail to fuse during the second month of fetal development. The coexistence of PBM and PD is an infrequent ***, we report an unusual variant of PBM associated with PD in a pediatric patient, in whom an anomalous communication existed between the CBD and dorsal pancreatic *** SUMMARY A boy aged 4 years and 2 mo was hospitalized for abdominal pain with nausea and jaundice for 5 d. Abdominal ultrasound showed cholecystitis with cholestasis in the gallbladder, dilated middle-upper CBD, and a strong echo in the lower CBD, indicating biliary stones. The diagnosis was extrahepatic biliary obstruction caused by biliary stones, which is an indication for endoscopic retrograde cholangiopancreatography(ERCP). ERCP was performed to remove biliary stones. During the ERCP, we found a rare communication between the CBD and dorsal pancreatic duct. After clearing the CBD with a balloon, an 8.5 Fr 4-cm pigtail plastic pancreatic stent was placed in the biliary duct through the major papilla. Six months later, his biliary stent was removed after he had no symptoms and normal laboratory tests. In the following 4-year period, the child grew up normally with no more attacks of abdominal *** We consider that ERCP is effective and safe in pediatric patients with PBM combined with PD, and can be the initial therapy to manage such cases,especially when it is combined with aberrant communication between the CBD and dorsal pancreatic duct.

关键词： Pancreaticobiliary maljunction Pancreas divisum Endoscopic retrograde cholangiopancreatography Variant Communication Children Case report

Endometriosis-associated endometrioid adenocarcinoma of the fallopian tube synchronized with endometrial adenocarcinoma:A case report

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World Journal of Clinical Cases 2023年第6期11卷 1365-1371页

作者： jian-yang feng Qing-Ping jiang Hong He Department of Obstetrics and Gynecology Guangdong Provincial Key Laboratory of Major Obstetric DiseaseThe Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510000Guangdong ProvinceChina Department of Pathology The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510000Guangdong ProvinceChina

BACKGROUND Endometriosis is a common gynecological disorder that affects women of reproductive *** is characterized by a cancer-like invasion of the extra-uterine endometrium and exhibits a strong association with ovarian clear cell cancer and endometrioid ***-associated fallopian tube endometrioid adenocarcinoma synchronized with endometrial adenocarcinoma was rarely *** SUMMARY A 49-year-old woman was referred to our hospital complaining about abnormal vaginal bleeding for three years following unsatisfactory ***-erative frozen sections unexpectedly unveiled an endometrioid cancer of the left fallopian tube with superficial invasion surrounded by diffuse endometriosis synchronized with endometrioid endometrial *** It was difficult to make a differential diagnosis when confronted with incidental findings of fallopian tube cancer lesions synchronized with endometrial *** key differential diagnosis of primary endometriosis-associated endometrioid adenocarcinoma of the fallopian tube from endometrial adenocarcinoma invol-vement relies on the pathological identification of malignant transformation in fallopian tube endometriosis disease.

关键词： Endometriosis-associated cancer Fallopian tube neoplasms Endometrial neoplasms Case report

Global Exponential Stability of a Class of Neural Networks with Delays

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 43-50页

作者： feng-jian yang Chao-long Zhang Chuan-yong Chen Xin-ming Chen Department of Computational Science Zhongkai University of Agriculture and Engineering Guangzhou 510225China

This paper is concerned with the stability of neural networks with time-varying delays. Under assumption that the nonlinear stimulate functions are Lipschitz continuous, by means of generalized Halanay inequalities, Dini＇s derivative and functional analysis techniques, several globally exponential stability criteria are established, which are only dependent on the parameters of the system.

关键词： Neural network Halanay's inequality delay globally exponential stability

Is appendoscope a new option for the treatment of acute appendicitis?

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World Journal of Gastroenterology 2024年第28期30卷 3386-3392页

作者： Shu-Jiong feng Yi-feng Zhou jian-feng yang Hong-Zhang Shen Guang-Xing Cui Xiao-feng Zhang Department of Gastroenterology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology Key Laboratory of Integrated Traditional Chinese and Western Medicine for Biliary and Pancreatic Diseases of Zhejiang ProvinceHangzhou 310000Zhejiang ProvinceChina Department of Gastroenterology Hangzhou Institute of Digestive DiseasesHangzhou 310000Zhejiang ProvinceChina

Acute appendicitis is a common surgical *** is commonly caused by obstruction of the appendiceal lumen due to fecaliths,tumors,or lymphoid *** over a century,appendectomy has been the primary treatment for acute *** Groves performed the first open appendectomy in *** 1983,Kurt Semm completed the first laparoscopic appendectomy,heralding a new era in ***,appendectomy is associated with certain complications and a rate of negative *** have suggested controversy over the impact of appendectomy on the development of inflammatory bowel disease and Parkinson’s disease,but an increasing number of studies indicate a possible positive correlation between appendectomy and colorectal cancer,gallstones,and cardiovascular *** the recognition that the appendix is not a vestigial organ and the advancement of endoscopic technology,Liu proposed the endoscopic retrograde appendicitis *** is an effective minimally invasive alternative for treating uncomplicated acute *** team has developed an appendoscope with a disposable digital imaging system operated through the biopsy channel of a colonoscope and successfully applied it in the treatment of *** article provides an overview of the progress in endoscopic treatment for acute appendicitis and offers a new perspective on the future direction of appendiceal disease treatment.

关键词： Acute appendicitis Endoscopic technology Endoscopic retrograde appendicitis therapy Appendoscope Appendiceal disease treatment

Effect of 6H-SiC crystal growth shapes on thermo-elastic stress in the growing crystal

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 622-627页

作者： Yong-gui Shi Pei-yun Dai jian-feng yang Zhi-hao Jin Hu-lin Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an 710049 China

The effect of 6H-SiC crystal growth shapes on the thermo-elastic stress distribution in the growing crystal was systematically in- vestigated by using a finite element method. The thermo-elastic stress distribution in the crystal with a flat growth shape was more homoge- neous than that in the crystals with concave and convex growth shapes, and the value of thermo-elasticity in the crystal with a fiat growth shape was also smaller than that in the two other types of crystals. The maximum values of thermo-elastic stress appeared at interfaces be- tween the crystal and the graphite lid. If the lid was of the same properties as 6H-SiC, the thermo-elastic stress would decrease in two orders of magnitude. Thus, to grow 6H-SiC single crystals of high quality, a transition layer of SiC formed by deposition or reaction is suggested; meanwhile the thermal field in the growth chamber should be adjusted to maintain the crystals with fiat growth shapes.

关键词： silicon carbide thermo-elasticity physical vapor transport single crystals crystal growth finite element method