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Preparation of fructone catalyzed by water-soluble Brφnsted acid ionic liquids

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Chinese Chemical Letters 2007年第1期18卷 24-26页

作者： Yuan Yuan Wang rong Wang Liang Chun Wu Li Yi dai Departmem of Chemistry East China Normal University Shanghai 200062 China Department of Chemistry Shanghai Normal University Shanghai 200234 China

Fructone （2-methyl-2-ethylacetoacetate-1, 3-dioxolane）, a flavouring material, has been synthesized from ethyl acetoacetate and glycol using five water-soluble Brφnsted acid ionic liquids as catalysts for the first time. The used Brφnsted acid ionic liquids include [Hmim]Tfa, [Hmim]Tsa, [Hmim]BF4, [Bmim]HSO4, [Bmim]H2P04, and [Hmim]BF4 showed the highest catalytic activity for the preparation of fructone. After reaction, the product could be isolated from the reaction system automatically, and the ionic liquid could be directly reused without dehydration.

关键词： Fructonc Water-soluble Brφnsted acid ionic liquids Catalyst

NOMA-Based Cooperative Relaying Transmission for the Industrial Internet of Things

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Computers, Materials & Continua 2022年第12期73卷 6513-6534页

作者： Yinghua Zhang Rui Cao Lixin Tian rong dai Zhennan Cao Jim Feng Dawning Information Industry Co. Ltd.Beijing100193China Dawning Information Industry Chengdu Co. Ltd.Chengdu610041China Amphenol Global Interconnect Systems San JoseCA95131US

With the continuous maturity of the fifth generation(5G)communications,industrial Internet of Things(IIoT)technology has been widely applied in fields such as smart *** smart factories,5G-based production line monitoring can improve production efficiency and reduce costs,but there are problems with limited monitoring coverage and insufficient wireless spectrum resources,which restricts the application of IIoT in the construction of smart *** response to these problems,we propose a hybrid spectrum access mechanism based on Non-Orthogonal Multiple Access(NOMA)cooperative relaying transmission to improve the monitoring coverage and spectrum *** there are a large number of production lines that need to be monitored in smart factories,it is difficult to realize real-time monitoring of all production lines due to insufficient wireless ***,we divide the production lines into high priority and low priority,and introduce cognitive radio technology to increase the number of monitoring production *** order to better describe the wireless fading channel environment in the factory,the two-wave with diffuse power(TWDP)channel is discussed to simulate the real factory environment and the outage probability of the secondary production line data transmission is derived in the proposed *** with the traditional mechanism,the proposed transmission mechanism can ensure the continuity of the secondary transmission,greatly reduce the outage probability of the secondary transmission,and improve the efficiency of the monitoring of the production lines.

关键词： Relay IIoT outage probability NOMA TWDP beam-forming

Flexible Aluminum Nanobowls for Alternative Preparation of Individual or a Small Number of Nanoparticles

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Chemical Research in Chinese Universities 2009年第2期25卷 143-146页

作者： SUN Yan CHEN Xin YUE Yang ZHANG rong-jun dai Ning National Laboratory for Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 P. R. China State Key Laboratory of Advanced Photonics Materials and Devices Department of Optical Science and Engineering Fudan University Shanghai 200433 P. R. China

The nanoscale aluminum bowls were derived from the porous alumina and were used as the flexible nanoscale reactors for the preparation of nanoparticles. Both single source precursor and preprepared nanoparticles were induced in the nanobowls by melting the precursor/polymer films spin-coated on aluminum nanobowls for the formation of nanostructural composites in the nanobowls. We have prepared a single nanoparticle or just a small number of metal（e.g. Pt） nanoparticles or semiconductor nanoparticles（e.g. CdSe or CdSe/ZnS core-shell nanostructures） in the nanobowls.

关键词： Porous alumina Nanoreactor Nanoparticle Array Polymer

Generation of cloned calves from different types of somatic cells

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Science China(Life Sciences) 2004年第5期47卷 470-476页

作者： GONG Guochun dai Yunping ZHU Huabing WANG Haiping WANG Lili LI rong WAN rong LIU Ying LI Ning State Key Laboratory for Agrobiotechnology China Agricultural UniversityBeijing 100094China Institute of Animal Science Chinese Academy of Agricultural ScienceBeijing 100094China

Six types of bovine somatic cell lines, including a granulosa cell line of Chinese red-breed yellow cattle (YGR), a granulosa cell line of Holstein cow (HGR), two skin fibroblast cell lines of two adult Holstein cows respectively (AFB1 and AFB2), a skin fibroblast cell line (FFB) and an oviduct epithelial cell line (FOV) of a Holstein fetus, were established. Somatic cell nu-clear transfer (SCNT) was carried out using these cells as nuclei donor, and a total of 12 healthy calves were cloned. The effects of different types of donor cells on developmental potential of bovine SCNT embryos were investigated. (i) There was no significant difference in development rates to the blastocyst stage for SCNT embryos from YGR and HGR (33.2% and 35.1%, respec-tively). Pregnancy rates of them were 33.3% and 30.2%, respectively; and birth rates were 16.7% and 11.6%, respectively. (ii) Development rates to the blastocyst stage for SCNT embryos from diffetent individuals (AFB1 and AFB2) differed significantly (27.9% and 39.4%, respectively, P <0.05). Pregnancy rates of them were 36.2% and 36.4%, respectively; and birth rates were 14.9 % and 27.3%, respectively. (iii) There was significant difference in development rates to the blastocyst stage for SCNT embryos from FFB and FOV of the same fetus (37.9% and 41.5%, respectively, P < 0.05). Pregnancy rates of them were 45.7% and 24.1%, respectively; and birth rates were 22.9 % and 10.3%, respectively. Finally, developmental potential of bovine SCNT embryos from all four types of somatic cells from Holstein cows (HGR, AFB, FFB and FOV) were compared. For in vitro development stage, development rates to the blastocyst stage for SCNT embryos from HGR, AFB, FFB and FOV were 35.1%A, 29.4%B, 37.9%A and 41.5%C, respectively (PABC<0.05); for in vivo development stage, pregnancy rates of them were 30.2%, 36.2%, 45.7% and 24.1%, respectively; and birth rates of them were 11.6%, 17.2%, 22.9% and 10.3% respec-tively.

关键词： nuclear transfer somatic cells bovine

Application of ammonia probe-assisted solid-state NMR technique in zeolites and catalysis

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Magnetic Resonance Letters 2022年第1期2卷 28-37,I0002页

作者： Chang Wang Weili dai guangjun Wu Naijia guan Landong Li School of Materials Science and Engineering&National Institute for Advanced Materials Nankai UniversityTianjin300350China Key Laboratory of Advanced Energy Materials Chemistry of the Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringNankai UniversityTianjin300071China

Solid-state NMR(ssNMR)spectroscopy is a powerful technique for characterizing the surface sites of solid acids and organic intermediates formed during the acid catalyzed *** a very useful probe molecule,ammonia is often utilized to determine the density of solidacids’surface sites by ssNMR *** present mini-review summarizes some of the latest research developments on the quantitative characterization of the acid sites and carbenium ions during the zeolite catalytic reaction by ammonia probe-assisted ssNMR spectroscopy.

关键词： Solid-state NMR spectroscopy Ammonia probe Acid sites Carbenium ions Zeolite catalysis

One step method of structure engineering porous graphitic carbon nitride for efficient visible-light photocatalytic reduction of Cr(Ⅵ)

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Journal of Materials Science & Technology 2021年第12期71卷 211-220页

作者： Xueru Chen Yin Zhang Dashui Yuan Wu Huang Jing Ding Hui Wan Wei-Lin dai Guofeng guan State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 210009China Department of Chemistry&Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200433China

Porous g-C_(3)N_(4)nanosheets(PCN)were prepared by the nickel-assisted one-step thermal polymerization ***(H2)which was produced by the reaction between nickel(Ni)foam and ammonia(NH3)defined the structure and properties of *** the formation of PCN,the participation of H2 not only enhanced the spacing between layers but also boosted the specific surface area that more active sites were ***,H2 promoted pores formation in the nanosheets,which was beneficial to the transfer of photons through lamellar structure and improved the absorption efficiency of visible ***,the obtained PCN possessed better Cr(Ⅵ)photocatalytic reduction efficiency than pure g-C_(3)N_(4).The reaction rate constant(k)of PCN(0.013 min-1)was approximately twice that of bare g-C_(3)N_(4)(0.007 min-1).Furthermore,the effects of original pH and concentration of Cr(Ⅵ)-containing solution on re moval efficiency of Cr(Ⅵ)were explored.A possible photocatalytic mecha nism was proposed based on the experiments of radical scavengers and photoelectrochemical characterizations.

关键词： Porous carbon nitride Nickel foam Hydrogen Cr(VI) Photocatalysis

Three dimensional temporal characteristics of ground motions and building responses in Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 287-299页

作者： dai Junwu Wang Yanru guan Qingsong Qi Xiaozhai Yang Xueshan Tong Mai George C. Lee Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China FEMA Washington DC USA MCEER University at Buffalo USA

In this paper, analytical results from 3D temporal characteristics of the responses of an RC frame building subjected to both a large aflershock and the main shock of Wenchuan M8.0 earthquake are presented. The ground motion records from the main shock were obtained from three nearby stations. The acceleration records were analyzed in terms of instantaneous tangential acceleration αv normal acceleration αN, Euclidean norm of acceleration vector lal, velocity vector ｜v｜, displacement vector ｜d｜, temporal curvature κ,κt, and temporal torsion γ and γ*** of the kinematic relationship between the above factors and some additional in depth information obtained from extensive analyses are provided and discussed.

关键词： 3D temporal characteristics analyses Wenchuan earthquake RC frame structure afiershock

Preparation of a Novel Green Fluorescent Carbon Quantum Dots and Application in Fe^(3+)-Specific Detection in Biological System

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Journal of Analysis and Testing 2024年第1期8卷 40-51页

作者： Xianfen Zhang Wenxian Wang Lijiao guan Huajie Chen dai Li Lipeng Zhang Saipeng Huang School of Chemical Engineering Northwest UniversityXi'an 710069China Chemical Technology Academy of Shandong Province Qingdao University of Science and TechnologyJinan250014China

Trace ferric ion(Fe^(3+))detection has attracted increasing attention as an essential and indispensable role in many physiological and pathological *** green-emitting carbon quantum dots(Green-CQDs)were obtained through a green and facile one-step hydrothermal method for the specific recognition and trace detection of Fe^(3+)in this *** optimal excitation and emission wavelengths of the CQDs were 395 nm and 490 nm,*** stokes shift was up to 95 nm,which can effectively reduce the background fluorescence *** addition,it also exhibited good water solubility,stability,and high *** fluorescence intensity of Green-CQDs was linearly related to the concentration of Fe^(3+)(range of 0-80μmol/L),and the detection limit was as low as 59 nmol/*** good properties were favorable and successful for Fe^(3+)detection in tap water,human serum samples and living *** addition,a fluorescence visual test paper(FP@CQDs)was prepared utilizing filter paper as carrier,which can quickly identify Fe^(3+)in real time,and is suitable for the visualization analysis of Fe^(3+)in *** an efficient nanoprobe,the Green-CQDs held great promise and bright prospects in practical application in prevention and early clinical diagnosis of Fe^(3+)-associated diseases.

关键词： Carbon quantum dots Fluorescent Hydrothermal Fe^(3+)-specific detection Cell imaging

Upregulation of UBAP2L in Bone Marrow Mesenchymal Stem Cells Promotes Functional Recovery in Rats with Spinal Cord Injury

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Current Medical Science 2018年第6期38卷 1081-1089页

作者： guan-lin LIN Huan WANG Jun dai Xiao LI Ming guan Qing DING Huai-xi WANG Huang FANG Department of Orthopaedics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Post-translational modifications of cellular proteins with ubiquitin or ubiquitin-like proteins regulate many cellular processes,such as cell proliferation,differentiation,apoptosis, signal transduction,intercellular immune recognition,inflammatory response,stress response,and DNA ***4/UBAP2L is an important member in the family of ubiquitin-like proteins,and its biological function remains *** study aimed to investigate the effect of UBAP2L on spinal cord injury (SCI).At first,rat bone marrow mesenchymal stem cells (BMSCs)were infected with adeno-associated virus to induce over-expression of ***,the infected BMSCs were transplanted into rats suffering from semi-sectioned *** results showed that the over-expression of Nice4 significantly promoted the proliferation and differentiation of BMSCs. In addition,the transplantation of infected BMSCs into the injured area of SCI rats improved the function repair of ***,the immunohistochemical and hematoxylin-eosin staining and RT-PCR results showed that the number of neuronal cells,oligodendrocytes,and astrocytes was significantly increased in the injured area,along with significantly upregulated expression ofcyclin D1 and p38 mitogen-activated protein kinase (MAPK).Meanwhile,the expression of caspase 3 protein was significantly *** conclusion,the over-expression of Nice4 gene can promote the functional recovery in SCI rats by promoting cell proliferation and inhibiting apoptosis. The results of this study indicate an alternative option for the clinical treatment of SCI.

关键词： bone marrow mesenchymal stem cells spinal cord injury ubiquitin-associated protein 2-like apoptosis proliferation