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Chinese Chemical Letters 2019年第2期30卷 389-391页

作者： wei lv junling Duan Shiyun Ai College of Chemistry and Material Science Shandong Agricultural University

A pair of "pinwheel-like" metal free phthalocyanines, (D)-and (L)-1,8,15,22-tetrakis (2-isopropyl-5-methylcyclohexoxyl)phthalocyanine (1) were isolated for the first time from cyclic tetramerization of (D)-and (L)-3- (2-isopropyl-5-methylcyclohexoxyl)-1,2-dicyanobenzene (2), respectively, in refluxing npentanol in the presence of lithium pentanoate followed by treatment with acetic acid. Owing to the steric hindrance of the bulky menthol groups, C4 tetra-a-substituted phthalocyanine 1 is the main phthalocyanine product generated and then could be purified readily by column chromatography. The newly prepared phthalocyanine has been characterized by a series of spectroscopic technique including MALDI-TOF mass, NMR, electronic absorption and IR spectroscopy in addition to elemental analysis. In addition, their electrochemical properties have also been studied by cyclic voltammetry measurement.

关键词： Phthalocyanine Chirality Synthesis Pinwheel-like Electrochemistry

Oxide formation mechanism of a corrosion-resistant CZ1 zirconium alloy

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Journal of Materials Science & Technology 2023年第16期147卷 6-15页

作者： Jing Hu weitong Lin Qingyang lv Changyuan Gao jun Tan China Nuclear Power Technology Research Institute Shenzhen 518000GuangdongChina

Tailoring microstructure and microchemistry by altering elemental compositions and thermomechanical treatment parameters enables superior corrosion performance in zirconium alloys for nuclear ***,our understanding of the relationship between various defects and the corrosion process remains limited in the newly developed zirconium *** we report the oxide formation mechanism of a CZ1 zirconium alloy with corrosion resistance surpassing many other zirconium alloy systems,such as Zircaloy-4 and Zr-1Nb-1Sn *** experiments of CZ1 alloy and Zr1Nb-1Sn model alloy were performed in 360°C water for up to 820 *** quantitively determined oxide phases by transmission Kikuchi diffraction(TKD)and examined lateral cracks,nano-porosity,and second-phase particles in oxide scales by transmission electron microscopy(TEM).Compared to the Zr-1Nb-1Sn model alloy,CZ1 alloy with lower Nb and Sn concentrations has shown smaller and lower-density lateral cracks but slightly larger oxide grains,reducing the diffusion route for oxidating *** analytical scanning and transmission electron microscopy,we demonstrate that due to the lower content of Sn(∼0.9 wt.%),there is less tetragonal ZrO_(2) phase formed in the oxide,and the level of tetragonal to the monoclinic phase transition is *** the Nb content(0.1 wt.%–0.3 wt.%)is lower than the solid solution limit of Nb in Zr,by introducing minor elements such as Fe,Cr,and Cu,there are still a reasonable number of second-phase particles to relieve the high stress associated with the metal-to-oxide *** mechanisms have substantially changed the density and distribution of lateral cracks in the oxide,thus reducing the corrosion rate of zirconium alloys.

关键词： Zirconium alloy Corrosion Oxide microstructure Lateral crack Tetragonal phase Nano-porosity

Valley switch effect in anα-T3 lattice-based superconducting interferometer

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Chinese Physics B 2024年第11期33卷 372-377页

作者： Ya-jun wei jun Wang School of Physics Southeast UniversityNanjing 210096China

Dirac electrons possess a valley degree of freedom,which is currently under investigation as a potential information *** propose an approach to generate and manipulate the valley-switching current(VSC)through Andreev reflection using an interferometer-based superconductor hybrid *** interferometer comprises a ring-shaped structure formed by topological kink states in the a-T3 lattice via carefully designed electrostatic *** results demonstrate the feasibility of achieving a fully polarized VSC in this device without contamination from cotunneling electrons sharing the same valley as the incident ***,we show that control over the fully polarized VSC can be achieved by applying a nonlocal gate voltage or modifying the global parameter *** former alters the dynamic phase of electrons while the latter provides an a-dependent Berry phase,both directly influencing quantum interference and thereby affecting performance in terms of generating and manipulating VSC,crucial for advancements in valleytronics.

关键词： valley switch effect valleytronics Andreev reflection a-T3 lattice

Numerical study of liquid coverage in a gas-liquid-solid packed bed

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Particuology 2015年第6期13卷 90-99页

作者： wei Du Lifeng Zhang Sha lv Panpan Lu Jian xu weisheng wei State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China The Key Laboratory of Catalysis China National Petroleum Corp. China University of Petroleum Beijing 102249 China Department of Chemical and Biological Engineering University of Saskatchewan Saskatoon SK Canada

In this work, computational fluid dynamics （CFD） simulations using the volume-of-fluid （VOF） model were employed to investigate the effects of liquid properties, liquid and gas flow rates, and wettability of particles on liquid maldistribution at the microscopic level in a fixed bed reactor. The simulation results show that the number of wetted particles decreases with increasing gas velocity, consequently leading to lower liquid-solid contact areas. The radial liquid distribution is greatly enhanced by increasing the liquid flow rate, whereas the time for the liquid to pass through the whole bed is decreased, as expected. Based on simulation results, it was found that the liquid-solid contact area can be increased by using liquids of high viscosities and more wettable particles. However, the flow-through time increases with increasing liquid viscosity. An increase in the gas density showed a minimal impact on the liquid flow- through time, and the liquid density does not impact the radial liquid distribution or the liquid flow time within a range of liquid densities typically encountered in the petrochemical industry.

关键词： CFD VOF Liquid-solid contact area Radial liquid distribution Fixed bed

Carbon nanotubes-reinforced polylactic acid/hydroxyapatite porous scaffolds for bone tissue engineering

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Frontiers of Materials Science 2024年第1期18卷 59-69页

作者： weiwei Lan Mingbo Wang Zhenjun lv jun Li Fuying Chen Ziwei Liang Di Huang Xiaochun wei weiyi Chen Research Center for Nano-Biomaterials&Regenerative Medicine Department of Biomedical EngineeringCollege of Biomedical EngineeringTaiyuan University of TechnologyTaiyuan 030024China Guangdong Engineering Technology Research Center of Implantable Medical Polymer Shenzhen Lando Biomaterials Co.Ltd.Shenzhen 518107China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030060China Department of Orthopaedics The Second Hospital of Shanxi Medical UniversityTaiyuan 030001China

In the field of bone defect repair,critical requirements for favorable cytocompatibility and optimal mechanical properties have propelled research efforts towards the development of composite *** this study,carbon nanotubes/polylactic acid/hydroxyapatite(CNTs/PLA/HA)scaffolds with different contents(0.5,1,1.5 and 2 wt.%)of CNTs were prepared by the thermally induced phase separation(TIPS)*** results revealed that the composite scaffolds had uniform pores with high porosities over 68%and high through *** addition of CNTs significantly enhanced the mechanical properties of resulted PLA/HA,in which the 1.5 wt.%CNTs/PLA/HA composite scaffold demonstrated the optimum mechanical behaviors with the bending elastic modulus of(868.5±12.34)MPa,the tensile elastic modulus of(209.51±12.73)MPa,and the tensile strength of(3.26±0.61)***,L929 cells on the 1.5 wt.%CNTs/PLA/HA scaffold displayed good spreading performance and favorable ***,it is expected that the 1.5 wt.%CNTs/PLA/HA scaffold has potential applications in bone tissue engineering.

关键词： CNTs/PLA/HA scaffold TIPS method mechanical property bone tissue engineering

Recovery of vanadium from vanadium slag by composite additive roasting-acid leaching process

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Journal of Iron and Steel Research International 2023年第7期30卷 1426-1439页

作者： jun-yi Xiang Ming-shuai Luo Xi Lu Lu-wei Bai Zhong-peng Zhu Qing-yun Huang Sheng-qin Zhang Kun-peng Guo Xue-wei lv College of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

To minimize the vanadium content in the vanadium extraction tailings, composite additive roasting with (CaO + MgO) and subsequent acid leaching process was carried out dealing with vanadium-bearing converter slag. The effect of additive with different MgO/(CaO + MgO) molar ratios on the roasting and leaching behaviours of vanadium slag was investigated, and the optimum process conditions were obtained. The results show that in the roasting experiment, under the conditions of roasting temperature of 850 ℃ and roasting time of 2 h, the main kinds of vanadate transformed from Ca_(2)V_(2)O_(7) to Ca_(5)Mg_(4)V_(6)O_(2)4 and then to Mg_(2)V_(2)O_(7) with the increase in the MgO/(CaO + MgO) molar ratio. In the leaching experiment, under the conditions of particle size less than 75 μm, leaching temperature of 50 ℃, pH of 2.5, liquid–solid ratio of 20:1, and MgO/(CaO + MgO) molar ratio of 1:3, the leaching efficiency of vanadium is increased by about 5%, but the substitution of MgO for most or all of CaO will significantly reduce the leaching efficiency of vanadium. Furthermore, the leaching efficiency of impurities (P and Cr) can also be decreased by a composite addictive (CaO + MgO) roasting process. The X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry, and X-ray photoelectron spectroscopy of the original vanadium slag and solid products of both roasting and leaching processes were also evaluated.

关键词： Vanadium slag Roasting Leaching Vanadate Recovery

f-Harmonic maps of doubly warped product manifolds

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Applied Mathematics(A Journal of Chinese Universities) 2013年第2期28卷 240-252页

作者： LU wei-jun Center of Mathematical Sciences Zhejiang University School of Science Guangxi University for Nationalities

In this paper,we study f-harmonicity of some special maps from or into a doubly warped product *** we recall some properties of doubly twisted product *** showing that the inclusion maps from Riemannian manifolds M and N into the doubly warped product manifold M ×（μ,λ） N can not be proper f-harmonic maps,we use projection maps and product maps to construct nontrivial f-harmonic *** we obtain some similar results given in [21],such as the conditions for f-harmonicity of projection maps and some characterizations for non-trivial f-harmonicity of the special product ***,we investigate non-trivial f-harmonicity of the product of two harmonic maps.

关键词： f-harmonic map doubly warped product manifold projection map product map.

The Rings Characterized by Minimal Left Ideals

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Acta Mathematica Sinica,English Series 2005年第3期21卷 473-482页

作者： jun Chao wei School of Science Mathematics Yangzhou University Yangzhou 225002 P. R. China

We study these rings with every minimal left ideal being a projective, direct summand and a p-injective module, respectively. Some characterizations of these rings are given, and the relations among them are obtained. With these rings, we characterize seinisiinple rings. Finally, we introduce MC2 rings, and give some characterizations of MC2 rings.

关键词： DS ring PS ring MP ring MC2 ring Minijective ring Singular ideal.

Recent advances in the application of sulfinic acids for the construction of sulfur-containing compounds

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Chinese Chemical Letters 2022年第1期33卷 97-114页

作者： Yufen lv Huanhuan Cui Na Meng Huilan Yue wei wei School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165China Qinghai Provincial Key Laboratory of Tibetan Medicine Research and CAS Key Laboratory of Tibetan Medicine Research Northwest Institute of Plateau BiologyXining 810008China School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832000China

Sulfur-containing organic compounds display wide applications in the field of materials science,synthetic chemistry,and pharmaceutical ***,numerous synthetic strategies have been developed for the synthesis of sulfur-containing compounds in synthetic *** recent years,the utilization of sulfinic acids as versatile synthons has emerged as attractive and powerful approach to access various organosulfur compounds through sulfonylation,sulfinylation or sulfenylation *** this review,we summarized the recent progress in the construction of various sulfur-containing compounds from sulfininc *** examples of substrates and the related reaction mechanisms are described *** review intends to provide readers a comprehensive understanding on the synthesis of sulfur-containing molecules from sulfinic acids and provide help for future synthetic research.

关键词： Sulfur-containing compounds Sulfinic acids Sulfonylation Sulfinylation Sulfenylation

Mechanism of high temperature reduction on iron carbide preparation with low-grade siderite

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Journal of Iron and Steel Research International 2022年第9期29卷 1357-1367页

作者： Dong Chen Ya-nan lv wei Zhao Fei-bao Wu wei-ang Ying School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina Department of Mechanical and Electrical Engineering Suzhou Institute of Industrial TechnologySuzhou 215104JiangsuChina

The carburization roasting followed by magnetic separation is a feasible method to utilize low-grade siderite *** order to enhance the carburization efficiency and separation effciency,high temperature reduction was carried out,and its mechanism was demonstrated by measuring carburization index,phase change,and microstructure under a carbon-sulfur infrared analyzer,an X-ray diffractometer,and a metallurgical *** results show that both the carburization effciency of siderite pellet and the separation efficiency of iron carbide from gangue are very ***,high temperature reduction is a useful way to enhance the carburization efficiency,as it can accelerate the reduction reaction rate and carburization reaction ***,high temperature reduction can improve the growth of iron carbide particle,promote the carburization efficiency,and strengthen the sodium modification reactions,thereby greatly accelerating the separation efficiency of iron carbide and *** the siderite pellets were reduced at 1050℃ for 90 min and carburized at 650℃ for 120 min,the carburization index of carburized pellets reached *** magnetic separation treatment,an electric furnace burden assaying 83.12 wt.%Fe and 6.96 wt.%C was prepared,and the corresponding iron recovery rate was 95.43%.The high temperature reduction is promisingly adopted to promote the utilization of low-grade siderite ores using carburization-magnetic separation technology.

关键词： Siderite High temperature reduction Carburization-Separation Iron carbide