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A Novel Method for Beckmann Rearrangement of Oximes with Silica Sulfuric Acid under Mild Condition

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Chinese Chemical Letters 2006年第5期17卷 617-620页

作者： lin Fei XIAO Jia jian PENG Chun gu XIA State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences and Graduate School of Chinese Academy of Science Lanzhou 730000

Silica sulfuric acid in which sulfuric acid is immobilized on the surface of silica gel via covalent bond has been proved to be green catalyst for liquid-phase Beckmann rearrangement of oximes in dried dioxane at room temperature. Excellent conversion and selectivity were acquired in the Beckmann rearrangement of cyclohexanone oxime. The catalyst system was recycled and reused.

关键词： Beckmann rearrangement oximes silica sulfuric acid.

Effect of strain on space charge layer in GaN nanowires investigated by in-situ off-axis electron holography

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Progress in Natural Science:Materials International 2017年第2期27卷 186-191页

作者： Xiao Chen Yanguo Wang Jikang jian lin gu Zhihua Zhang Liaoning Key Materials Laboratory for Railway Dalian Jiaotong University Beijing National Laboratory of Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences School of Physics Science and Technology Xinjiang University Collaborative Innovation Center of Quantum Matter

Effect of strain on space charge(SC) layer in nanowires(NWs) has been examined by in situ off-axis electron holography, where GaN NWs attach to an Au electrode inside a transmission electron microscope(TEM). Based on the phase image reconstructed from the complex hologram, the width of SC layer in a strained GaN NW is significantly reduced to about 60 nm, comparing to the 85 nm of the unstrained NW. About 29% reduction of the SC layer in the strained GaN NW resulted from significant decrease of electrons flowed from the GaN into Au. First principle calculations show that the strain reduced bandgap of GaN, narrowing the difference between GaN NW and Au electrode in Fermi level.

关键词： Space charge layer Off-axis electron holography In-situ strain TEM GaN NW

Controlling charges distribution at the surface of a single GaN nanowire by in-situ strain

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Progress in Natural Science:Materials International 2017年第4期27卷 430-434页

作者： Xiao Chen Yanguo Wang Jikang jian lin gu Zhihua Zhang Liaoning Key Materials Laboratory for Railway Dalian Jiaotong University Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences School of physics science and technology Xinjiang University Collaborative Innovation Center of Quantum Matter

Effect of the strain on the charge distribution at the surface of a GaN semiconductor nanowire(NW) has been investigated inside transmission electron microscope(TEM) by in-situ off-axis electron holography. The outer and inner surfaces of the NW bent axially under compression of two Au electrodes were differently strained,resulting in difference of their Fermi levels. Consequently, the free electrons flow from the high Fermi level to the low level until the two Fermi levels aligned in a line. The potential distributions induced by charge redistribution in the two vacuum sides of the bent NW were examined respectively, and the opposite nature of the bounded charges on the outer and inner surfaces of the bent NW was identified. The results provide experimental evidence that the charge distribution at the surfaces of a single GaN NW can be controlled by different strains created along the NW.

关键词： Nanowire Strain Charge distribution Electron holography TEM

Biocompatibility of polyetheretherketone for the treatment of orbital bone defects

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International Journal of Ophthalmology(English edition) 2020年第5期13卷 725-730页

作者： Rui-Dong gu Fan Xiao lin Wang Kai-jian Sun lin-lin Chen Department of Ophthalmology the Fourth People’s Hospital of ShenyangShenyang 110031Liaoning ProvinceChina

AIM: To investigate the biocompatibility and therapeutic effects of polyetheretherketone(PEEK) on recovery of a rabbit orbital ***: Totally 16 New Zealand rabbits were used to establish an orbital bone defect model and then randomly divided into two groups. PEEK was implanted in the experimental group. The control group was blank, and no substance was implanted. The model rabbits were sacrificed at 4 and 8 wk, and examined by general observations, histology, electron microscopy, Western blotting, and realtime polymerase chain ***: No infection or rejection occurred after PEEK implantation, and biocompatibility was good. The relative expression of vascular endothelial growth factor(VEGF) protein in the experimental group was significantly higher than that in the control group postoperatively(P<0.05). Bone defect repair in the experimental group was significantly better than that in the control group in the same period and some osteogenesis was ***: PEEK has good biocompatibility and efficacy for the treatment of orbital bone defects in a rabbit model.

关键词： polyetheretherketone histocompatibility orbital defect orbital burst fracture three-dimensional printing rabbit

Interfacial engineering regulated by CeOx to boost efficiently alkaline overall water splitting and acidic hydrogen evolution reaction

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Journal of Materials Science & Technology 2022年第25期120卷 129-138页

作者： jian Chen Zhen Hu Yang Ou Qinghua Zhang Xiaopeng Qi lin gu Tongxiang Liang College of Rare Earth Jiangxi University of Science and TechnologyGanzhou 341000China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Institute of Physics Chinese Academy of ScienceBeijing 100190China

Development of a low-cost and durable bifunctional electrocatalyst with high catalytic activity by hybridizing rare earth metal and non-noble metal is of utmost ***,a bifunctional electrocatalyst consisting of MoO_(2)and CeO_(x)heterostructure is synthesized via interfacial ***,due to its unique hetero-interface with abundant oxygen vacancies,the MoO_(2)-CeO_(x)_(x)/NF is able to exhibit outstanding hydrogen evolution reaction(HER) performance with an overpotential of 26 mV at 10 mA cm^(-2),and a preferable oxygen evolution reaction(OER) overpotential of 272 mV at 100 mA cmin 1 M *** recorded HER and OER overpotentials of MoO_(2)-CeO_(x)/NF are clearly smaller than those of Pt/C(HER overpotential of 27 mV) and RuO(OER overpotential of 393 mV) at the same current *** importantly,MoO_(2)-CeO_(x)/NF can also exhibit good HER activity with an overpotential of 50 mV at 10 mA cmin acidic ***,it is expected that this work can offer a new approach in the realization of high-catalytic alkaline overall water splitting and acidic HER performance through the rational design of rare-earth metal and non-noble metal heterostructure.

关键词： Heterostructure Oxygen vacancies Cerium oxide Overall water splitting

Fluorescence Nanoscopy in Neuroscience

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Engineering 2022年第9期16卷 29-38页

作者： Yangyundou Wang jian lin Qiming Zhang Xi Chen Haitao Luan Min gu Center for Artificial-Intelligence Nanophotonics School of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

Fluorescence nanoscopy provides imaging techniques that overcome the diffraction-limited resolution barrier in light microscopy,thereby opening up a new area of research in biomedical imaging in fields such as ***,we review the foremost fluorescence nanoscopy techniques,including descriptions of their applications in elucidating protein architectures and mobility,the real-time determination of synaptic parameters involved in neural processes,three-dimensional imaging,and the tracking of nanoscale neural *** conclude by discussing the prospects of fluorescence nanoscopy,with a particular focus on its deployment in combination with related techniques(e.g.,machine learning)in neuroscience.

关键词： Fluorescence imaging Diffraction limit Nanoscale resolution Neuroscience

Insight of the stability and activity of platinum single atoms on ceria

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Nano Research 2019年第6期12卷 1401-1409页

作者： Xuxu Ye Hengwei Wang Yue lin Xinyu Liu lina Cao jian gu Junling Lu Department of Chemical Physics iChEMCAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Single-atom catalysts (SACs) have recently attracted broad attention in the catalysis field due to their maximized atom efficiency and unique catalytic *** atomic-level understanding of the interaction between the metal atoms and support is vital for developing stable and high-performance *** this work,Pt1 single atoms with Ioadings up to 4 wt.% were fabricated on ceria nanorods using the atomic layer deposition *** understand the Pt-O-Ce bond interfacial interactions,the stability of Pt1 single atoms in the hydrogen reducing environment was extensively investigated by using in situ diffuse reflectance infrared Fourier transform spectroscopy CO chemisorption *** was found that ceria defect sites,metal Ioadings and high-temperature calcination are effective ways to tune the stability of Pt1 single atoms in the hydrogen environment.X-ray photoemission spectroscopy further showed that Pt1 single atoms on ceria are dominantly at a +2 valence state at the defect and step edge sites,while those on terrace sites are at a +4 *** above tailored stability and electronic properties of Pt1 single atoms are found to be strongly correlated with the catalytic activity in the dry and water-mediated CO oxidation reactions.

关键词： single atom catalyst Pt1/CeO2 metal-support interaction stabilitywater-mediated CO oxidation

Discrete numerical modeling of granular materials considering crushability

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Journal of Mountain Science 2017年第4期14卷 758-770页

作者： QIAN jian-gu gu jian-bo gu Xiao-qiang HUANG Mao-song Key Laboratory of Geotechnieal and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

The aim of this study is to numerically investigate the influence of particle breakage on the mechanical behavior of granular materials using a discrete element method(DEM). To enable particle crushing, non-crushable elementary particles are boned together to represents the granular aggregates which can be crushed when the external force exceeds its strength. The flaw of the aggregate was also modeled by randomly distributed void. Single particle crushing tests were carried out to determine the distribution of particle strength. The results of single particle crushing tests illustrate that the simulated single particle fracture strength and pattern agree well with the Weibull's distribution *** oedometer tests, drained monotonic and cyclic triaxial tests were also carried out to investigate the crushing of the aggregates and the associated mechanical behaviors. The effect of confining pressure on the crushing of aggregates and the mechanical behavior was also analyzed. It was found that the peak stress and dilation decrease significantly when particle crushing was *** deformation behavior of the specimen is essentially controlled by two factors: particle rearrangement-induced dilation and particle crushing-induced contraction. The increase of permanent strain and the reduction of dilation were observed during cyclic loading and they tend to reach a stable state after a certain number of cycles. The crushing of aggregate is most significant in the first two cycles. The results also indicated that for the same axial strain the volumetric strain and the bound breakage in the cyclic loading tests are significantly larger than that in the monotonic loading tests,especially at high cyclic stress ratio.

关键词： DEM simulation Granular materials Crushing Monotonic and Cyclic triaxial test

Three new aspochalasin derivatives from the marine-derived fungus Spicaria elegans

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Chinese Chemical Letters 2010年第7期21卷 824-826页

作者： Zhen jian lin Tian Jiao Zhu Li Chen Qian Qun gu Key Laboratory of Marine Drugs Chinese Ministry of EducationInstitute of Marine Drugs and FoodOcean University of ChinaQingdao 266003China

Three new aspochalsins（R-T）（1-3） were isolated from the marine-derived fungus Spicaria *** structures were elucidated on the basis of comprehensive spectral analysis including 1D and 2D NMR techniques,and HR-ESI-MS.

关键词： Aspochalasin Spicaria elegans Marine fungus