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Polyoxometalates-based heterogeneous catalysts in acid catalysis

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Science China Chemistry 2021年第7期64卷 1117-1130页

作者： Lifei Lian Huaiying Zhang Sai An Wei Chen Yu-fei song State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Acid catalysis,one of the most important industrial processes,suffers from the toxicity,corrosion and recyclability problems of conventional homogeneous acid ***,the development of green heterogeneous acid catalysts becomes the focus of fundamental research and industrial *** a class of discrete anionic metal-oxygen clusters with tunable structure at the molecular and atomic scales,polyoxometalates(POMs)benefit from their super strong Br?nsted acidity,high proton mobility,and thermal ***-based heterogeneous catalysts have been used as the potential green alternatives to conventional homogeneous acid *** this review,we summarize recent progress on the design strategies of the POMs-based heterogeneous catalysts and their catalytic properties in acid-catalyzed reactions,where they are combined with functionalized cations,modified through covalent interactions,supported onto the non-precious metal support,and introduced into the framework of porous *** design,functional strategies and catalytic performance of these POMs-based heterogeneous catalysts in specific acid-catalyzed reactions are emphasized.

关键词： polyoxometalates solid acid catalyst acid catalysis heterogeneous catalysis esterification

Surfactant-free oil/water and bicontinuous microemulsion composed of benzene,ethanol and water

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Chinese Chemical Letters 2010年第7期21卷 880-883页

作者： fei song Jie Xu Wan Guo Hou Key Laboratory for Colloid and Interface Chemistry of Education Ministry Shandong UniversityJinan 250100China College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao 266042China

Generally,a microemulsion consists of oil,water,surfactant and sometimes ***,we report a novel suffactant-free microemulsion（denoted as SFME） composed of benzene,water and ethanol without the amphiphilic molecular structure of traditional *** phase behavior of the ternary system was investigated,finding that there were a single-phase region and a two-phase region in ternary phase *** electrical conductivity measurement was employed to investigate the microregion of the single-phase region,and a bicontinuous microregion and a benzene-in-water（O/W） microemulsion microregion were identified,which was confirmed by freeze-fracture transmission electron microscopy（FF-TEM） *** sizes of the microemulsion droplets are in the range of 20-50 nm.

关键词： Surfactant-free microemulsion Phase behavior Conductivity FF-TEM

ICN Based Vehicle-to-Cloud Delivery for Multimedia Streaming in Urban Vehicular Networks

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China Communications 2016年第9期13卷 103-112页

作者： Wei Quan fei song Chengxiao Yu Mingchuan Zhang National Engineering Laboratory for Next Generation Internet Technologies School of Electronic and Information EngineeringBeijing Jiaotong University College of Information Engineering Henan University of Science and Technology

Mobile multimedia streaming is an open topic in vehicular environment. Due to the high intermittent links, it has become a critical challenge to deliver high quality video streaming in vehicular networks. In this paper, we reform the Information Centric Networking （ICN） concept for multimedia delivery in urban vehicular networks. By leveraging the 1CN perspective, we highlight that vehicular peers can obtain multimedia chunks via the vehicle-to-cloud （V2C） approach to improve the delivery quality. Based on this, we propose a lightweight multipath selection strategy to guide the network system to adaptively adjust the forwarding means. Extensive simulations show that the proposed solution can optimize the utilization of network paths, lighten network loads as well as avoid wasting resources.

关键词： information centric networking vehicle-to-cloud multimedia streaming VANET

Synthesis of Some Novel 2,6- Dimethoxyhydroquinone-3-mercaptoacetyl-peptide Conjugates as Potential Antitumor Agents

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Chinese Chemical Letters 2000年第8期11卷 667-670页

作者： Yu fei song Pin YANG Leung SHEH Institute of Molecular Science Shanxi UniversityTaiyuan 030006 Department of Chemistry Tunghai UniversityTaichungTaiwan 407-04

This paper reports an ongoing study of the use of short chain peptides as carriers of a potential antitumor agents: 2,6-dimethoxyhydroquinone-3-mercaptoacetic acid (DMQ-MA). Three new peptide-DMQ-MA conjugates: DMQ-MA-arg-arg-ome, DMQ-MA-lys(cbz)-arg-ome, DMQ-MA-lys(cbz)-arg-arg-ome were synthesized by coupling protected amino acids in solution and the next conjugation was achieved by reacting with pentafluorophenyl ester of DMQ-MA in DMF, and further study on their ability to inhibit human pulmonary adenocarcinoma cell line (PC-9 cells) and oral epidermoid carcinoma cell line (KB) are investigating.

关键词： 2 6-dimethoxyhydroquinone-3-mercaptoacetic acid

Quantum coherence and ground-state phase transition in a four-chain Bose–Hubbard model

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Communications in Theoretical Physics 2021年第8期73卷 182-188页

作者： Ji-Guo Wang Lin-Qi Guo Ya-fei song Department of Mathematics and Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China Institute of Applied Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China

We study the quantum coherence and ground-state phase transition of a four-chain Bose–Hubbard model with the long-range interaction. In a special four-chain Bose–Hubbard model,i.e., each chain only has one optical potential, four types of the ground-state phases are discovered. The effects of the disorder, the on-site interaction and the long-range interaction on the quantum coherence are studied. For the system without the long-range interaction, the quantum coherence changes from one periodic oscillation to two periodic oscillations as the onsite interaction increases. By considering the long-range interaction, the quantum coherence goes back to one periodic oscillation again. The on-site interaction itself suppresses the quantum coherence, both the on-site interaction and long-range interaction together enhance the quantum coherence with the weak disorder. If the disorder strength is increased beyond a critical value,they start to suppress the quantum coherence. In a regular four-chain Bose–Hubbard model, i.e.,each chain has many optical potentials, the ground-state phase transitions are obtained by using the cluster Gutzwiller mean-field method. Exotic ground-state phases are found, i.e., superfluid phase, integer Mott insulator phase, supersolid phase and loophole insulator phase. The combination of the loophole insulator phase and the supersolid phase expands the lobes with the half-integer filling per site for the small ratio β = t_(‖)/t_(⊥).

关键词： Bose-Hubbard model quantum coherence ground-state phase transition

Heme oxygenase-1 protects donor livers from ischemia/reperfusion injury:The role of Kupffer cells

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World Journal of Gastroenterology 2010年第10期16卷 1285-1292页

作者： Zeng, Zhong Huang, Han-fei Chen, Ming-Qing song, fei Zhang, Yu-Jun Kunming Med Coll Organ Transplantat Ctr Affiliated Hosp 1 Kunming 650032 Yunnan Province Peoples R China Third Mil Med Univ Southwest Hosp Inst Hepatobiliary Surg Chongqing 400038 Peoples R China

AIM:To examine whether heme oxygenase (HO)-1 overexpression would exert direct or indirect effects on Kupffer cells activation, which lead to aggravation of reperfusion ***: Donors were pretreated with cobalt protoporphyrin (CoPP) or zinc protoporphyrin (ZnPP), HO-1 inducer and antagonist, respectively. Livers were stored at 4℃ for 24 h before transplantation. Kupffer cells were isolated and cultured for 6 h after liver ***: Postoperatively, serum transaminases were significantly lower and associated with less liver injury when donors were pretreated with CoPP, as compared with the ZnPP group. Production of the cytokines tumor necrosis factor-α and interleukin-6 generated by Kupffer cells decreased in the CoPP group. The CD14 expression levels (RT-PCR/Western blots) of Kupffer cells from CoPP-pretreated liver grafts ***: The study suggests that the potential utility of HO-1 overexpression in preventing ischemia/reperfusion injury results from inhibition of Kupffer cells activation.

关键词： Heme oxygenase-1 Kupffer cells Ischemia/reperfusion injury Liver transplantation

Unique NiFe–NiCoO2 hollow polyhedron as bifunctional electrocatalysts for water splitting

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Journal of Energy Chemistry 2019年第6期28卷 74-80页

作者： Rong Shi Jiaxin Wang Zhi Wang Tengfei Li Yu-fei song State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology

It is of significance to design of stable and cost-effective electrocatalyst for water splitting with high efficiency in an alkaline *** major obstacles for practical application of water splitting devices are lack of high-efficiency and low-cost electrocatalysts with low overpotential for both HER and *** this paper,we report a NiFe alloy decorated NiCoO2 hollow polyhedron(denoted as Ni Fe–Ni Co O2)by using[NiFe(CN)6]- intercalated NiCo–LDH as *** evidenced by the electrochemical active surface area,the resultant Ni Fe–Ni Co O2 composite shows unique hollow nanostructure,which can not only provide abundant mass transport channels,but also increase the contact area of the NiFe–Ni Co O2 material with the *** overpotential(η)demand is 286 mV for OER and 102 mV for HER at the current density of 10 mA/cm2 in an alkaline medium of 1 M KOH for the NiFe/NiCoO2 *** work provides a new pathway for preparation of the highly efficient bifunctional electrocatalysts for water splitting.

关键词： Layered double hydroxides (LDHs) Hollow polyhedron Water splitting

Extracting 3D model feature lines based on conditional random fields

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第7期14卷 551-560页

作者： Yao-ye ZHANG Zheng-xing SUN Kai LIU Mo-fei song fei-qian ZHANG State Key Laboratory for Novel Software Technology Nanjing University

We propose a 3D model feature line extraction method using templates for guidance. The 3D model is first projected into a depth map, and a set of candidate feature points are extracted. Then, a conditional random fields (CRF) model is established to match the sketch points and the candidate feature points. Using sketch strokes, the candidate feature points can then be connected to obtain the feature lines, and using a CRF-matching model, the 2D image shape similarity features and 3D model geometric features can be effectively integrated. Finally, a relational metric based on shape and topological similarity is proposed to evaluate the matching results, and an iterative matching process is applied to obtain the globally optimized model feature lines. Experimental results showed that the proposed method can extract sound 3D model feature lines which correspond to the initial sketch template.

关键词： Nonphotorealistic rendering Model feature lines Conditional random fields Feature line metrics Iterative matching

Additive manufacturing of porous magnesium alloys for biodegradable orthopedic implants:Process,design,and modification

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Journal of Materials Science & Technology 2024年第15期182卷 79-110页

作者： Bo Peng Haojing Xu fei song Peng Wen Yun Tian Yufeng Zheng State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Institute for Precision Medicine Tsinghua University Beijing Tsinghua Changgung HospitalBeijing 102218China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Department of Orthopedics Peking University Third HospitalBeijing 100191China Department of Materials Science and Engineering Peking UniversityBeijing 100871China

Biodegradable magnesium(Mg)alloys exhibit excellent biocompatibility,adequate mechanical properties,and osteogenic *** can contribute to complete recovery of damaged tissues without concerns about a second surgery and have achieved clinical applications in orthopedic and cardiovascular *** scaffolds can provide functions such as bone integration and adjustable mechanical properties,thus widely used for bone *** manufacturing(AM)offers the advantages of design freedom and high precision,enabling the reliable production of porous scaffolds with customized *** combination of biodegradable Mg alloys,porous scaffolds,and AM processes has created tremendous opportunities for the precision treatment of bone *** article reviews the current development in the additive manufacturing process and design of Mg alloy biodegradable orthopedic implants,fo-cusing on chemical compositions,structural design,surface treatment,and their effects on mechanical properties,degradation behavior,and ***,the future perspective of porous Mg alloy biodegradable orthopedic implants is proposed.

关键词： Biodegradable magnesium alloys Additive manufacturing Laser powder bed fusion Orthopedic implants Porous structure design Degradation behavior