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Chinese Journal of Chemistry 2024年第21期42卷 2614-2620页

作者： Feng-Cheng Jia zi-Yi Yuan Na luo Shuang-xi Gu xiao-Qiang Hu School of Chemistry and Environmental Engineering School of Chemical Engineering and Pharmacyand Key Laboratory of Green Chemical ProcessMinistry of EducationWuhan Institute of TechnologyWuhanHubei430205 China Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education School of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhanHubei430074 China

Concise assembly of spirooxindoles is of great significance but a challenging task in modern organic *** herein is an unusual base-promoted[4+2]spiroannulation of rarely used isatin-derivedβ-silylcarbinols with o-halogen aromatic ketones,which enables rapid and modular synthesis of six-membered carbocyclic spirooxindoles in high yields with excellent functional group tolerance(>50 examples).Mechanistic experiments revealed that this reaction involved a Peterson olefination,Michael addition and intramolecular C(sp^(3))arylation *** variegated synthetic derivatization of target products and successful construction of bioactive molecules further illustrate the synthetic potential in spirooxindole-related drug discovery.

关键词： Cascade reaction Spirooxindole Peterson olefination C(sp^(3))arylation of oxindole Transition-metal-free

Palladium-Catalyzed[4+4]Cycloaddition of Homo-TMM All-Carbon 1,4-Dipole Precursors for Construction of Benzofuro[3,2-b]azocines and Furo[3,2-b]azocines

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Chinese Journal of Chemistry 2023年第21期41卷 2825-2831页

作者： Ying Chen Meng Zang Weije Wang Yang-zi Liu xiaoyan luo Wei-Ping Deng Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism School of PharmacyEast China University of Science and TechnologyShanghai 200237China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiangNormal UniversityJinhuaZhejiang 321004China

We developed a novel Pd-catalyzed[4+4]cycloaddition of(benzo)furan-derived azadienes with homo-TMM all-carbon 1,4-dipoles in situ generated fromα-allyl malonate derivatives,affording an array of benzofuro[3,2-b]azocines and furo[3,2-b]azocines with good to excellent yields(up to 96%)and exclusive *** methodology featured mild reaction conditions and good functional group *** synthetic utility was demonstrated by a gram-scale ***,the catalytic asymmetric[4+4]cycloaddition version has also been explored.

关键词： Pd-catalyzed [4+4]cycloaddition Homo-TMM 1,4-dipoles Methodology and reactions Medium-ring compounds Regioselectivity

Defect engineering of hierarchical porous carbon microspheres for potassium-ion storage

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Rare Metals 2022年第10期41卷 3446-3455页

作者： xin-Fei Wu zi-Jian Li Jin-xiao Liu Wen luo Jean-Jacques Gaumet Li-Qiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China Department of Physics School of ScienceWuhan University of TechnologyWuhan430070China Laboratoire de Chimie et Physique:Approche Multi-échelles des Milieux Complexes(LCP-A2MC)Institut Jean BarriolUniversitéde LorraineMetz57070France

Owing to adjustable microstructure and stable physiochemical properties,carbon-based materials are regarded as promising materials as anodes for potassium-ion batteries(PlBs).Building amorphous structure and introducing defects are favorable methods to generate active sites and improve the electrochemical performances of carbon-based *** this work,we develop a facile carbonization method to prepare sulfur-doped amorphous carbon microspheres with hierarchical structure and modulated defects concentration(S-CM-700) for potassium *** from the special microstructure,S-CM-700 exhibits the optimal performance and obtains high reversible capacity of 199.6 mAh·g^(-1) at 100 mA·g^(-1),excellent rate property and prominent durability(0.0055%capacity decay per cycle during 1800 cycles).Kinetics analysis and electrochemical characterization are carried out to reveal that the potassium storage could be boosted by regulating the defect level,layer spacing and the content of *** work provides a general synthesis approach to prepare sustainable carbon anodes for advanced PlBs.

关键词： Potassium-ion battery(PIB) Defect engineering Amorphous carbon Hierarchical structure Anode

Oxidative Dehydrogenation of 1-Butene to 1,3-Butadiene Using CO2 over Cr-SiO2 Catalysts Prepared by Sol-gel Method

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Chemical Research in Chinese Universities 2018年第4期34卷 609-615页

作者： GAO Biao luo Yajun MIAO Changxi YUE Yinghong YANG Weimin HUA Weiming GAO zi Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 P. R. China Shanghai Research Institute of PetrochemicaI Technology SINOPEC Shanghai 201208 P. R. China

A series of Cr-SiO2 catalysts with a Cr content（mass fraction） ranging from 0.5% to 9% was prepared by a sol-gel method. The catalysts were characterized by xRD, N2 adsorption, EDx elemental mapping, Raman spectros- copy, UV-Vis spectroscopy, xPS and H2-TPR, and their catalytic behavior in the dehydrogenation of 1-butene to 1,3-butadiene（BD） using CO2 as a soft oxidant was studied. The initial BD yield is well correlated with the amount of Cr6~ in the fresh catalysts. The highest BD yield of ca. 34% is achieved on the catalysts with 5%--9% Cr at 600 ~C -1 -1 and weight hourly space velocity（WHSV） of 4.5 g＇geat＇h ~ The promoting effect of CO2 on the BD yield was ob- served, which can be attributed to the reaction coupling between a simple dehydrogenation of 1-butene and the re- verse water-gas shift reaction as well as regaining the oxidation state（lattice oxygen） of reduced Cr3＋ species due to the mild oxidation ability of CO2. The Cr-SiO2 catalyst exhibits higher BD yield than the Cr catalyst supported on SBA-15, which is attributed to the higher amount of Cr6＋ present on the former catalyst.

关键词： 1,3-Butadiene CO2 oxidative dehydrogenation Cr-based catalyst Sol-gel method

Pretreatment of cromolyn sodium prior to reperfusion attenuates early reperfusion injury after the small intestine ischemia in rats

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World Journal of Gastroenterology 2007年第38期13卷 5139-5146页

作者： zi-Qing Hei xiao-Liang Gan Gang-Jian luo Shang-Rong Li Jun Cai Department of Anesthesiology The Third Affiliated Hospital Sun Yat-sen University Guangzhou 510630 Guangdong Province China

AIM: To investigate the effects of Cromolyn Sodium (CS) pretreated prior to reperfusion on the activity of intestinal mucosal mast cells (IMMC) and mucous membrane of the small intestine in ischemia-reperfusion (IR) injury of rats. METHODS: Thirty-two Sprague-Dawley (SD) rats were randomly divided into four groups: sham group (group S), model group (group M), high and low dosage of CS groups, (treated with CS 50 mg/kg or 25 mg/kg, group C1 and C2). Intestinal IR damage was induced by clamping the superior mesenteric artery for 45 min followed by reperfusion for 60 min. CS was intravenouly administrated 15 min before reperfusion. Ultrastructure and counts of IMMC, intestinal structure, the expression of tryptase, levels of malondisldehyde (MDA), TNF-α, histamine and superoxide dismutase (SOD) activity of the small intestine were detected at the end of experiment. RESULTS: The degranulation of IMMC was seen in group M and was attenuated by CS treatment. Chiu’s score of group M was higher than the other groups. CS could attenuate the up-regulation of the Chiu’s score, the levels of MDA, TNF-α, and expression of tryptase and the down-regulation of SOD activity and histamine concentration. The Chiu’s score and MDA content were negatively correlated, while SOD activity was positively correlated to the histamine concentration respectively in the IR groups. CONCLUSION: Pretreated of CS prior to reperfusion protects the small intestine mucous from ischemia- reperfusion damage, the mechanism is inhibited IMMC from degranulation.

关键词： Ischemia Reperfusion injury Intestinal mucosal mast cells Histamine Tumor necrosis factor-α

Benefits of combination of electroencephalography, short latency somatosensory evoked potentials, and transcranial Doppler techniques for confirming brain death

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第11期9卷 916-920页

作者： Kang WANG Yuan YUAN zi-qi xU xiao-liang WU Ben-yan luo Department of Neurology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Intensive Care Unlit the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 3 10003 China

Objective: Optimization of combining electroencephalography (EEG), short latency somatosensory evoked potentials (SLSEP) and transcranial Doppler (TCD) techniques to diagnose brain death. Methods: One hundred and eleven patients (69 males, 42 females) from the major hospitals of Zhejiang Province were examined with portable EEG, SLSEP and TCD devices. Re-examinations occurred ≤12 h later. Results: The first examination revealed that the combination of SLSEP and EEG led to more sensitive diagnoses than the combination of SLSEP and TCD. Re-examination confirmed this and also revealed that the combination of TCD and EEG was the most sensitive. Conclusion: The results show that using multiple techniques to diagnose brain death is superior to using single method, and that the combination of SLSEP and EEG is better than other combinations.

关键词： Brain death Electroencephalography (EEG) Short latency somatosensory evoked potentials (SLSEP) TranscranialDoppler (TCD)

Sparse and Low-Rank Covariance Matrix Estimation

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Journal of the Operations Research Society of China 2015年第2期3卷 231-250页

作者： Sheng-Long Zhou Nai-Hua xiu zi-Yan luo Ling-Chen Kong Department of Applied Mathematics Beijing Jiaotong UniversityBeijing 100044China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

This paper aims at achieving a simultaneously sparse and low-rank estimator from the semidefinite population covariance *** first benefit from a convex optimization which develops l1-norm penalty to encourage the sparsity and nuclear norm to favor the low-rank *** the proposed estimator,we then prove that with high probability,the Frobenius norm of the estimation rate can be of order O(√((slgg p)/n))under a mild case,where s and p denote the number of nonzero entries and the dimension of the population covariance,respectively and n notes the sample ***,an efficient alternating direction method of multipliers with global convergence is proposed to tackle this problem,and merits of the approach are also illustrated by practicing numerical simulations.

关键词： Covariance matrix Sparse and low-rank estimator Estimation rate Alternating direction method of multipliers

Preparation and Characterization of Amorphous Silicon Oxide Nanowires

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Journal of China University of Mining and Technology 2007年第4期17卷 587-589页

作者： NI zi-feng YING Peng-zhan luo Yong LI Zhuo-su School of Mechanical and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China School of Materials Science and Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China

Large-scale amorphous silicon nanowires (SiNWs) with a diameter about 100 nm and a length of dozens of micrometers on silicon wafers were synthesized by thermal evaporation of silicon monoxide (SiO). Scanning electron microscope (SEM) and transmission electron microscope (TEM) observations show that the silicon nanowires are smooth. Selected area electron diffraction (SAED) shows that the silicon nanowires are amorphous and en-ergy-dispersive x-ray spectroscopy (EDS) indicates that the nanowires have the composition of Si and O elements in an atomic ratio of 1:2,their composition approximates that of SiO2. SiO is considered to be used as a Si sources to produce SiNWs. We conclude that the growth mechanism is closely related to the defect structure and silicon monoxide followed by growth through an oxide-assisted vapor-solid reaction.

关键词： silicon nanowires amorphous one-dimensional

Geometric edge effect on the interface of Au/CeO_(2)nanocatalysts for CO oxidation

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Nano Research 2024年第6期17卷 4986-4993页

作者： Hongpeng LiuZhongliang Cao Siyuan Yang Qingye Ren Zejian Dong Wei Liu zi-An Li xing Chen Langli luo Institute of Molecular Plus Tianjin UniversityTianjin 300072China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics(DICP)Chinese Academy of SciencesDalian 116023China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures and School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

The oxide supports play a crucial role in anchoring and promoting the active metal species by geometric confinement and chemical *** design and synthesis of the well-defined oxide support with specific morphology such as size,shape,and exposed facets have attracted extensive research efforts,which directly reflects on their catalytic *** this study,using an Au/CeO_(2)-nanorod model catalyst,we demonstrate an edge effect on the Au/CeO_(2)interfacial structure,which shows a prominent effect on the structure-performance relationship in the CO oxidation *** specific“edge-interface”structure features an“edge-on”Au nanoparticles position on rod-shaped CeO_(2)support,confirmed by atomic-scale electron microscopy characterization,which introduces additional degrees of freedom in coordination environment,chemical state,bond length,and *** with theocratical calculations and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)investigations,we confirmed that this“edge-interface”has distinct adsorption properties due to the change of O vacancy formation energy as well as the chemical states of Au resulting from the electron transfer and redistribution between the metal and the *** results demonstrate a non-conventional geometric effect of rod-shaped supported metal catalysts on the catalytic performance,which could provide insights into the atomic-precise utilization of catalysts.

关键词： ceria nanorod supported catalyst edge-effect atomic scale

Diboron-mediated palladium-catalyzed asymmetric transfer hydrogenation using the proton of alcohols as hydrogen source

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Science China Chemistry 2021年第10期64卷 1743-1749页

作者： Bo Wu Jimin Yang Shu-Bo Hu Chang-Bin Yu zi-Biao Zhao Yi luo Yong-Gui Zhou Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The developments of hydrogen sources stand at the forefront of asymmetric reduction. In contrast to the well-studied alcohols as hydrogen sources via β-hydride elimination, the direct utilization of the proton of alcohols as a hydrogen source for activatormediated asymmetric reduction is rarely explored. Herein we report the proton of alcohols as a hydrogen source in diboronmediated palladium-catalyzed asymmetric transfer hydrogenation of 1,3-diketones and indoles, providing a series of chiral β-hydroxy ketones and indolines with excellent yields and enantioselectivities. This strategy would be useful for the synthesis of chiral deuterium-labelled compounds due to the ready availability of deuterium-labelled alcohols. Mechanistic investigations and DFT calculations revealed that active chiral Pd-H species was generated from the proton of alcohols by activating of tetrahydroxydiboron, hydrogen transfer was the rate-determining step, and the reaction preferred Pd(0)-catalyzed mechanism.

关键词： proton of alcohols hydrogen source asymmetric reduction