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An alkaline fusion mechanism for aluminate rare earth phosphor:cation-oxoanion synergies theory

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Rare Metals 2019年第4期38卷 299-305页

作者： yi-fan liu Shen-Gen Zhang Bo liu Han-Lin Shen Institute for Advanced Materials and Technology University of Science and Technology Beijing

Waste aluminate rare earth phosphor is an important rare earth elements (REEs) secondary resource, which mainly consists of BaMgAl1()O|7:Eu2+(BAM) and CeMgAl11O19:Tb^3+(CMAT). Alkaline fusion process is widely used to recycle REEs from aluminate phosphor, but the related theory remains imperfect. In this paper, a series of alkaline fusion experiments of CMAT were performed to describe the phase change law of CMAT reactions. Based on comprehensive analysis, cation-oxoanion synergies theory (COST) was proposed to explain the aluminate phosphor structure damage. On the mirror plane of aluminate phosphor crystal structure, alkali metal cations (Na^+,K^+) would substitute rare earth ions, while free oxoanion (OH^-, CO3^2-, O2^2-) can combine with rare earth ions. These two ionic forces ensure that rare earth ions can be substituted by cations. Then, the structure is decomposed. Morphological analysis shows that observable expression of COST can be described by shrinking core model after simplification. Reaction rate constant calculated indicates that the reaction degree is nanometers per second. COST provides a more complete mechanism, and it can help improve rare earth recycling technology furtherly.

关键词： Aluminate phosphor Alkaline fusion Rare earth Mechanism

Numerical investigations of the interactions between bubble induced shock waves and particle based on OpenFOAM

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Journal of Hydrodynamics 2024年第2期36卷 355-362页

作者： Jia-xin Yu Jin-sen Hu Yu-hang liu yi-fan liu Dan Gao Yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System Ministry of EducationSchool of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The presence of particles and the shock waves generated by the cavitation bubbles can significantly affect the safety and the performance of hydrodynamic *** the present paper,the shock waves generated by cavitation bubble collapsing near the particle are numerically investigated based on the OpenFOAM together with the numerical schlieren for the shock wave *** numerical results reveal that the stand-off distance is one of the paramount factors affecting the interactions between the particle and the shock *** different kinds of shock waves(e.g.,bubble-inception,jet formation,particle reflected and jet-split shock waves)are observed during the bubble collapsing near the *** stand-off distance smaller than 0.5 or larger than 1.1,the maximum pressure at particle surface generated by the bubble growth can surpass those of the collapse stage.

关键词： Particle-bubble interaction shockwaves jetdynamics

Mechanism of CeMgAl_(11)O_(19):Tb^(3+) alkaline fusion with sodium hydroxide

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Rare Metals 2015年第3期34卷 189-194页

作者： Hu liu Shen-Gen Zhang De-An Pan yi-fan liu Bo liu Jian-Jun Tian Alex A.Volinsky Institute for Advanced Materials and Technology School of Materials Science and EngineeringUniversity of Science and Technology Beijing Department of Mechanical Engineering University of South Florida

Comprehensive CeMgA111O19： Tb3＋（CTMA） disintegration via alkaline fusion was discussed. The rare earth （RE） elements in CTMA were dissolved by HC1 completely after alkaline fusion. Relationships between the alkaline fusion temperature and various properties of the compounds were examined by various techniques to elu- cidate their roles in the expected CTMA disintegration. X-ray diffraction （XRD） analysis indicates the phase transformation sequence. A scientific hypothesis of crystal structure disintegration presents that sodium ions substitute for the europium and barium ions in the mirror plane and magnesium ions in the spinel block successively, resulting in that more oxygen vacancies and interstitial sodium ions appear. The unit cell [P63/mmc （194）] breaks from the mirror plane. Then it is decomposed into NaA102, and magnesium, cerium, and terbium ions combine with free OH- into MgO, Tb2O3 and CeO2; Tb2O3 and CeO2 change into Ceo.6Tbo.O2-x. In the end, the rare earth oxide is recycled easily by the acidolysis. The mechanism provides fundamental basis for recycling of REEs from waste phosphors.

关键词： Alkaline fusion mechanism Recycle CeMgAlllO19:Tb3+ Structure transformations

Flexible carbon fiber-based composites for electromagnetic interference shielding

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Rare Metals 2022年第11期41卷 3612-3629页

作者： Hong-Yan Zhang Jin-Yao Li ying Pan yi-fan liu Nasir Mahmood Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China RMIT University School of EngineeringMelbourneVic3001Australia

With the rapid development of electronic information technology,the waste electromagnetic radiation generated by the wireless and various other electronic devices has caused serious harm to human *** development of high-efficiency flexible electromagnetic interference(EMI)shielding materials has become one of the most effective ways to mitigate the increasingly serious problem of electromagnetic *** carbon fiber composites possess most of the physical requirements needed for EMI shielding applications,including high electrical conductivity,large specific surface area,light weight,flexibility,porous structure,and adjustable physical and chemical properties,and various morphology of carbon fibers-based composites applied *** this review,the primary EMI shielding mechanism of carbonfiber-based materials is *** carbon fiber suffers from a low absorption efficiency when used for EMI shielding by itself,it is usually combined with additional EMI filling ***,the methods of adding EMI filler materials to the carbon fiber framework and the influence of different fillers on the EMI shielding performance are also *** addition,the novel structural designs of flexible carbon fiber-based EMI shielding materials,including fiber orientation,core-shell structure,and multilayer heterostructure,are summarized in terms of their classification,which includes composites with metal,polymer,nano-carbon,and *** review concludes with a brief discussion of the challenges,research directions,and future prospects of carbon-fiber-based EMI shielding materials.

关键词： Carbon fibers Electromagnetic interference shielding Flexible Composites

A review of helical carbon materials structure,synthesis and applications

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Rare Metals 2021年第1期40卷 3-19页

作者： Ding-Chuan Wang Yu Lei Wei Jiao yi-fan liu Chun-Hong Mu Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China School of Public Affairs and Law Southwest Jiaotong UniversityChengdu 610031China National Engineering Research Center of Electromagnetic Radiation Control Materials State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengdu 610054China

The helical structures possess unique physical and chemical properties,such as superelasticity,high specific strength,chirality,and electromagnetic cross-polarization *** the development of nanoscience and nanotechnology,helical structures with various scales have been discovered or synthesized *** them,the helical carbon materials receive much attention around the ***,we present a brief review of the development of helical carbon materials in terms of structures,synthesis techniques and mechanisms,and *** controllable designing of catalysts,carbon sources and reaction parameters plays a key role to optimize the properties of the helical carbon *** the same time,the applications in microwave absorption devices,sensors,catalysts,energy conversions and storage devices,and solar cell are also *** the good chemical and physical properties,helical carbon materials have a good application prospect in many *** potential issues and future opportunities of the helical carbon materials are also proposed.

关键词： Helical carbon materials Coil Synthesis mechanisms Applications

Acetylene/argon mixture plasma to build ultrathin carbon bridge of CF_(x)/C/MnO_(2) for high-rate lithium primary battery

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Rare Metals 2024年第6期43卷 2574-2584页

作者： Da-Wei Zou Xing-Guang Fu Gao-Bang Chen yi-fan liu Bao-Shan Wu Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 31300lChina

Forming an ultrathin conducting layer on a fluorinated carbon(CFx)surface for reducing severe electrochemical polarization in lithium/fluorinated carbon primary batteries(Li/CF_(x))remains a considerable challenge for achieving batteries with excellent rate ***,CFxwas modified by using acetylene/argon mixture plasma combined with MnO_(2)*** CF_(x)/C/MnO_(2)composite effectively reduced the voltage hysteresis and improved the electrochemical performance of Li/CF_(x).The excellent rate performance of CF_(x)/C/MnO_(2)was due to the high electrochemical activity provided by the atomicscale conductive carbon layer and ultrafine MnO_(2)*** with pristine CF_(x),the charge transfer resistance of the optimized CF_(x)/C/MnO_(2)decreased from 218.5 to 48.2Ω,the discharge rate increased from 2C to 10C,and the power density increased from 3.11 to 13.44 kW·g^(-1),The intrinsic reason for the enhanced rate performance was attributed to the fact that the ultrathin carbon layer acted as a conductive bridge to reduce the voltage hysteresis at the initial stage of the Li/CF_(x)discharge,and the high electrochemical activity of the ultrafine MnO_(2)particles provided a faster lithium-ion diffusion rate.

关键词： C_(2)H_(2)/Ar plasma Fluorinated carbon Lithium primary battery MnO_(2)

Effects of Helicobacter pylori eradication on atrophic gastritis and intestinal metaplasia: A 3-year follow-up study

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World Journal of Gastroenterology 2005年第41期11卷 6518-6520页

作者： Bin Lu Ming-Tao Chen yi-Hong fan Yan liu Li-Na Meng Department of Gastroenterology Affiliated Hospital of Zhejiang Traditional Chinese Medicine College Hangzhou 310006Zhejiang Province China

AIM: To investigate the effect of H pylori eradication on atrophic gastritis and intestinal metaplasia (IM).METHODS: Two hundred and fifty-nine patients with atrophic gastritis in the antrum were included in the study, 154 patients were selected for H pylori eradication therapy and the remaining 105 patients served as untreated group. Gastroscopy and biopsies were performed both at the beginning and at the end of a 3-year follow-up study. Gastritis was graded according to the updated Sydney ***: One hundred and seventy-nine patients completed the follow-up, 92 of them received H pylori eradication therapy and the remaining 87 H pyloriinfected patients were in the untreated group. Chronic gastritis, active gastritis and the grade of atrophy significantly decreased in H pylori eradication group (P＜0.01). However, the grade of IM increased in H pylori -infected group (P＜0.05).CONCLUSION: H pylori eradication may improve gastric mucosal inflammation, atrophy and prevent the progression of IM.

关键词： Hpylori Atrophic gastritis Tntestinal metaplasia

Secondary electron emission and photoemission from a negative electron affinity semiconductor with large mean escape depth of excited electrons

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Chinese Physics B 2023年第4期32卷 677-690页

作者：谢爱根董红杰刘亦凡 School of Physics and Optoelectronic Engineering Nanjing University of Information Science and TechnologyNanjing 210044China Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean Nanjing University of Information Science&TechnologyNanjing 210044China Jiangsu international Joint Laboratory on Meteorological Photonics and Optoelectronic Detection Nanjing University of Information Science&TechnologyNanjing 210044China

The formulae for parameters of a negative electron affinity semiconductor(NEAS)with large mean escape depth of secondary electrons A(NEASLD)are *** methods for obtaining parameters such asλ,B,E_(pom)and the maximumδandδat 100.0 keV≥E_(po)≥1.0 keV of a NEASLD with the deduced formulae are presented(B is the probability that an internal secondary electron escapes into the vacuum upon reaching the emission surface of the emitter,δis the secondary electron yield,E_(po)is the incident energy of primary electrons and E_(pom)is the E_(po)corresponding to the maximumδ).The parameters obtained here are analyzed,and it can be concluded that several parameters of NEASLDs obtained by the methods presented here agree with those obtained by other *** relation between the secondary electron emission and photoemission from a NEAS with large mean escape depth of excited electrons is investigated,and it is concluded that the presented method of obtaining A is more accurate than that of obtaining the corresponding parameter for a NEAS with largeλ_(ph)(λ_(ph)being the mean escape depth of photoelectrons),and that the presented method of calculating B at E_(po)>10.0 keV is more widely applicable for obtaining the corresponding parameters for a NEAS with largeλ_(ph).

关键词： negative electron affinity semiconductor secondary electron emission photoemission the probability secondary electron yield large mean escape depth of excited electrons

hMex-3A is associated with poor prognosis and contributes to the progression of hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 147-153页

作者： yi-fan liu Xiao-Yan Sun Jia-Kai Zhang Zhi-Hui Wang Zhi-Gang Ren Jie Li Wen-Zhi Guo Shui-Jun Zhang Zhengzhou Key Laboratory of Hepatobiliary and Pancreatic Diseases and Organ Transplantation Zhengzhou 450052China Henan Key Laboratory of Digestive Organ Transplantation Zhengzhou 450052China Department of Hepatobiliary and Pancreatic Surgery the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Open and Key Laboratory of Hepatobiliary and Pancreatic Surgery and Digestive Organ Transplantation at Henan Universities the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Infectious Diseases the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Background:HMex-3A,an RNA-binding protein,was found to be associated with ***,the roles of h Mex-3A in hepatocellular carcinoma(HCC)progression remained ***:The different expression of h Mex-3A between HCC tissues and non-tumor tissues was evaluated using The Cancer Genome Atlas ***,the h Mex-3A expression was evaluated in HCC tissues using Western blotting and q *** was performed to investigate the association between h Mex-3 A level and clinicopathological features including prognosis in HCC *** addition,we used si-h Mex-3A to knockdown h Mex-3A in HCC cells to test Cell Counting Kit-8,colony formation,cell migration and ***:The h Mex-3A expression was significantly elevated in HCC *** of the clinicopathological parameters suggested that h Mex-3A expression was significantly associated with pathological grade(P=0.019)and TNM stage(P=0.001)in ***,univariate and multivariate Coxregression analyses revealed that high h Mex-3A expression(HR=1.491,95%CI:1.107–2.007;P=0.009)was an independent risk factor for overall survival in HCC ***,we confirmed that si-h Mex-3A could significantly inhibit HCC cell proliferation,migration,and invasion in ***:HMex-3A may contribute to the progression of HCC and might be used as a novel therapeutic target and prognostic marker in HCC.

关键词： Hepatocellular carcinoma hMex-3A Targeted therapy