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controllable synthesis of novel nanoporous manganese oxide catalysts for the direct synthesis of imines from alcohols and amines

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2438-2446页

作者： Fushan Chen Songlin Zhao Tao Yang Taotao Jiang Jun Ni Houfeng Xiong Qunfeng Zhang Xiaonian Li Industrial Catalysis Institute of Zhejiang University of Technology Hangzhou 310014China Jiangxi Province Engineering Research Center of Ecological Chemical Industry Jiujiang UniversityJiujiang 332005China School of Pharmaceutical and Chemical Engineering Taizhou UniversityTaizhou 318000China

A novel template-free oxalate route was applied to synthesize different mesoporous manganese oxides(amorphous manganese oxide(AMO),Mn5 O8,Mn3 O4,Mn O2)in the narrow temperature range from 350°C to 400°C by controlling the calcination conditions,which were employed as the efficient catalysts for the oxidative coupling of alcohols with amines to *** chemical and structural properties of the manganese oxides were characterized by the methods of thermogravimetry analysis and heat flow(TG-DSC),X-ray diffraction(XRD),nitrogen sorption,scanning electron microscope(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),H2 temperature-programmed reduction(H2-TPR),and inductively coupled plasma optical emission spectrometry(ICP-OES)*** structures of different manganese oxides were confirmed by *** M-350(AMO)presented the maximum surface area,amorphous nature,the lowest reduction temperature,the higher(Mn3++Mn4+)/Mn2+ratio,and the higher adsorbed oxygen species compared to other *** the catalysts,M-350 showed the best catalytic performance using air as an oxidant,and the conversion of benzyl alcohol(BA)and the selectivity of N-benzylideneaniline(NBA)reached as high as 100%and 97.1%respectively at the lower reaction temperature(80°C)for 1 h.M-350 had also the highest TOF value(0.0100 mmol·mg-1·h-1)compared to the other manganese oxide *** catalyst was reusable and gave 95.8%conversion after 5 reuse tests,the XRD pattern of the reactivated M-350 did not show any obvious *** oxygen mobility and(Mn3++Mn4+)/Mn2+ratio were found to play the important roles in the catalytic activity of aerobic reactions.

关键词： Oxalate route controllable synthesis Manganese oxide Imine synthesis Heterogeneous catalysis Aerobic oxidation

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controllable fabrication of self-organized nano-multilayers in copper–carbon films

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Chinese Physics B 2019年第3期28卷 309-316页

作者： Wei-Qi Wang Li Ji Hong-Xuan Li Xiao-Hong Liu Hui-Di Zhou Jian-Min Chen State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

In order to clarify the influence of methane concentration and deposition time on self-organized nano-multilayers,three serial copper-carbon films have been prepared at various methane concentrations with different deposition times using a facile magnetron sputtering deposition system. The ratios of methane concentration(CH4/Ar+CH4) used in the experiments are 20%, 40%, and 60%, and the deposition times are 5 minutes, 20 minutes, and 40 minutes, *** the difference in the growth conditions, self-organizing multilayered copper-carbon films are prepared at different deposition times by changing methane concentration. The film composition and microstructure are investigated by x-ray photoelectron spectroscopy(XPS), x-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), and high-resolution transmission electron microscopy(HRTEM). By comparing the composition and microstructure of three serial films, the optimal growth conditions and compositions for self-organizing nano-multilayers in copper-carbon film are acquired. The results demonstrate that the self-organized nano-multilayered structure prefers to form in two conditions during the deposition process. One is that the methane should be curbed at low concentration for long deposition time,and the other condition is that the methane should be controlled at high concentration for short deposition time. In particular, nano-multilayered structure is self-organized in the copper-carbon film with copper concentration of 10-25 at.%.Furthermore, an interesting microstructure transition phenomenon is observed in copper-carbon films, that is, the nanomultilayered structure is gradually replaced by a nano-composite structure with deposition time and finally covered by amorphous carbon.

关键词： nano-multilayers self-organized controllable fabrication copper–carbon films

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controllable growth of GeSi nanostructures by molecular beam epitaxy

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Journal of Semiconductors 2018年第6期39卷 51-65页

作者： Yingjie Ma Tong Zhou Zhenyang Zhong Zuimin Jiang State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences State Key Laboratory of Surface Physics Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education) and Department of PhysicsFudan University School of Physics and Optoelectronic Engineering Shandong University of Technology

We present an overview on the recent progress achieved on the controllable growth of diverse GeSi al- loy nanostructures by molecular beam epitaxy. Prevailing theories for controlled growth of Ge nanostructures on patterned as well as inclined Si surfaces are outlined firstly, followed by reviews on the preferential growth of Ge nanoislands on patterned Si substrates, Ge nanowires and high density nanoislands grown on inclined Si surfaces, and the readily tunable Ge nanostructures on Si nanopillars. Ge nanostructures with controlled geometries, spatial distributions and densities, including two-dimensional ordered nanoislands, three-dimensional ordered quantum dot crystals, ordered nanorings, coupled quantum dot molecules, ordered nanowires and nanopillar alloys, are dis- cussed in detail. A single Ge quantum dot-photonic crystal microcavity coupled optical emission device demon- stration fabricated by using the preferentially grown Ge nanoisland technique is also introduced. Finally, we sum- marize the current technology status with a look at the future development trends and application challenges for controllable growth of Ge nanostructures.

关键词： Ge Si molecular beam epitaxy nanostructures controllable patterned substrates inclinedsurfaces preferential growth

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Magnetically controllable multimode interference in topological photonic crystals

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Light(Science & Applications) 2024年第5期13卷 998-1005页

作者： Weiyuan Tang Mudi Wang Shaojie Ma Che Ting Chan Shuang Zhang New Cornerstone Science Laboratory Department of PhysicsThe University of Hong KongHong KongChina. Department of Physics The Hong Kong University of Science and TechnologyHong KongChina. Department of Optical Science and Engineering Fudan UniversityShanghai 200433China

Topological photonic insulators show promise for applications in compact integrated photonic circuits due to their ability to transport light robustly through sharp *** number of topological edge states relies on the difference between the bulk Chern numbers across the boundary,as dictated by the bulk edge *** interference among multiple topological edge modes in topological photonics systems may allow for controllable functionalities that are particularly desirable for constructing reconfigurable photonic *** this work,we demonstrate magnetically controllable multimode interference based on gyromagnetic topological photonic insulators that support two unidirectional edge modes with different *** successfully achieve controllable power splitting in experiments by engineering multimode interference with the magnetic field intensity or the frequency of *** work demonstrates that manipulating the interference among multiple chiral edge modes can facilitate the advancement of highly efficient and adaptable microwave devices.

关键词： multimode controllable microwave

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Adiabatic cooling for cold polar molecules on a chip using a controllable high-efficiency electrostatic surface trap

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Chinese Physics B 2014年第12期23卷 148-154页

作者：李胜强许亮夏勇汪海玲印建平 State Key Laboratory of Precision Spectroscopy Department of Physics East China Normal University

We propose a controllable high-efficiency electrostatic surface trap for cold polar molecules on a chip by using two insulator-embedded charged rings and a grounded conductor plate. We calculate Stark energy structure pattern of ND3 molecules in an external electric field using the method of matrix diagonalization. We analyze how the voltages that are applied to the ring electrodes affect the depth of the efficient well and the controllability of the distance between the trap center and the surface of the chip. To obtain a better understanding, we simulate the dynamical loading and trapping processes of ND3 molecules in a ｜J, KM = ｜1,-1 state by using classical Monte–Carlo method. Our study shows that the loading efficiency of our trap can reach ～ 88%. Finally, we study the adiabatic cooling of cold molecules in our surface trap by linearly lowering the potential-well depth（i.e., lowering the trapping voltage）, and find that the temperature of the trapped ND3 molecules can be adiabatically cooled from 34.5 m K to ～ 5.8 m K when the trapping voltage is reduced from-35 k V to-3 k V.

关键词： controllable high-efficiency surface trap cold polar molecules

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controllable preparation of nanosized TiO_2 thin film and relationship between structure of film and its photocatalytic activity

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Science China Chemistry 2003年第2期46卷 184-190页

作者：魏刚张元晶熊蓉春 College of Material Science and Engineering Beijing University of Chemical Technology

TiO2 nano-crystalline film and fixed bed photocatalytic reactor were prepared by the sol-gel process using tetrabutylorthotitanate as a precursor and glass tube as the substrate. XRD, AFM, SEM and thickness analysis results indicate that the preparation of nano-crystalline film can be controlled by optimizing experiment process. Under the optimized process, the phase of TiO2 in film is anatase, and the grain size is 3–4 nm. The size of particles, which is about 20-80 nm, can be controlled. The thickness of monolayer film is in nanometer grade. The thickness and particles size in films growing on nanometer film can also be controlled in nanometer grade. As a result, the crack of film can be effectively avoided. Rhodamine degradation results using UV-Vis spectrophotometer show that the activity of nano-crystalline film in the photocatalytic reactor has a good relation with the diameter of TiO2 particles, that is, the film shows high activity when the size is 20 –30 nm and greatly reduced when the size is above 60 nm. The activity of film does not decrease with the increase of film thickness, and this result indicates that nano-crystalline film has no ill influence on the transmissivity of ultraviolet light.

关键词： nanosized TiO2, nanosized thin film, controllable preparation, photocatalytic activity.

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Bionic Flapping Pectoral Fin with controllable Spatial Deformation

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Journal of Bionic Engineering 2019年第5期16卷 916-930页

作者： Yueri Cai Lingkun Chen Shusheng Bi Guoyuan Li Houxiang Zhang Robotics Institute Beihang UniversityBeijing 100191China Department of Ocean Operations and Civil Engineering Norwegian University of Science and TechnologyAalesund 6025Norway

This paper presents the design of a bionic pectoral fin with fin rays driven by multi-joint *** by the cownose ray,the bionic pectoral fin is modeled and simplified based on the key structure and movement parameters of the cownose ray's pectoral fin.A novel bionic propulsion fin ray composed of a synchronous belt mechanism and a slider-rocker mechanism is designed and optimized in order to minimize the movement errors between the designed fin rays and the spanwise curves observed from the cownose ray,and thereby reproducing an actively controllable flapping deformation.A bionic flapping pectoral fin prototype is developed *** verify that the bionic pectoral fin flaps consistently with the design rule extracted from the cownose *** in a towing tank are set up to test its capability of generating the lift force and the propulsion *** movement parameters within the usual propulsion capabilities of the bionic pectoral fm are utilized:The flapping frequency of 0.2 Hz-0.6 Hz,the flapping amplitude of 3°-18°,and the phase di^rence of 10°-60°.The results show that the bionic pectoral fin with actively controllable spatial deformation has expected propulsion performance,which supports that the natural features of the cownose ray play an important role in designing and developing a bionic prototype.

关键词： cownose ray bionic pectoral fin controllable deformation multiple fin rays propulsion perfonnance

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Size-controllable synthesis and high-performance formic acid oxidation of polycrystalline Pd nanoparticles

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Rare Metals 2019年第2期38卷 115-121页

作者： Hui-Hui Wang Jin-Feng Zhang Ze-Lin Chen Meng-Meng Zhang Xiao-Peng Han Cheng Zhong Yi-Da Deng Wen-Bin Hu Tianjin Key Laboratory of Composites and Functional Materials and Key Laboratory of Advanced Ceramics and Machining Technology (Ministry of Education) Tianjin University

A facile approach was developed for the synthesis of polycrystalline palladium nanoparticles(Pd NPs)by using tannic acid(TA) as green reagent and stabilizer in a 30 ℃ water bath. The size of Pd NPs can be tuned in a range of 10–60 nm simply by adjusting the concentration of Pd precursor. The catalytic activity and stability of the as-obtained Pd NPs toward formic acid oxidation were analyzed. It is found that these Pd NPs with different sizes exhibit size-dependent and enhanced formic acid oxidation performance compared to the commercial Pd black catalyst. It should be noted that the Pd catalysts with an average size of 24 nm demonstrate the best catalytic activity and stability among the other prepared Pd NPs, which can be ascribed to its larger electrochemical surface area(ECSA)and polycrystalline structure with defects.

关键词： Polycrystalline palladium nanoparticle Size controllable Tannic acid: Room temperature Formic acid oxidation

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A novel near-infrared light responsive 4D printed nanoarchitecture with dynamically and remotely controllable transformation

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Nano Research 2019年第6期12卷 1381-1388页

作者： Haitao Cui Shida Miao Timothy Esworthy Se-jun Lee Xuan Zhou Sung Yun Hann Thomas J.Webster Brent T.Harris Lijie Grace Zhang Department of Mechanical and Aerospace Engineering The George Washington UniversityWashingtonDC 20052USA Department of Chemical Engineering Northeastern UniversityBostonMA 02115USA Department of Neurology and Pathology Georgetown UniversityWashingtonDC 20007USA Departments of Electrical and Computer Engineering The George Washington UniversityWashingtonDC 20052USA Department of Biomedical Engineering The George Washington UniversityWashingtonDC 20052USA Department of Medicine The George Washington UniversityWashingtonDC 20052USA

Four-dimensional (4D) printing is an emerging and highly innovative additive manufacturing process by which to fabricate pre-designed,self-assembly structures with the ability to transform over ***,one of the critical challenges of 4D printing is the lack of advanced 4D printing systems that not only meet all the essential requirements of shape change but also possess smart,dynamic capabilities to spatiotemporally and instantly control the shape-transformation ***,we present a facile 4D printing platform which incorporates nanomaterials into the conventional stimuli-responsive polymer,allowing the 4D printed object to achieve a dynamic and remote controlled,on-time and position shape transformation.A proof-of-concept 4D printed brain model was created using near-infrared light (NIR) responsive nanocomposite to evaluate the capacity for controllable 4D transformation,and the feasibility of photothermal stimulation for modulating neural stem cell *** novel 4D printing strategy can not only be used to create dynamic 3D patterned biological structures that can spatiotemporally control their shapes or behaviors of transformation under a human benign stimulus (NIR),but can also provide a potential method for building complex self-morphing objects for widespread applications.

关键词： near-infrared light responsive four-dimensional (4D) printing dynamically and remotely controllable graphene brain neural stem cell

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Magnetic and thermosensitive luminescent nanocomposites based on Fe_3O_4/SiO_2/poly(N-isopropylacrylamide)/lanthanidepolyoxometalates and their controllable luminescence properties

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Journal of Rare Earths 2018年第7期36卷 733-738页

作者： Jun Wang Si Chen Hao Liu Wuke Li College of Chemistry Central China Normal University

Magnetic and temperature-responsive luminescent composites based on poly（N-isopropylacrylamide）,magnetic nanoparticles and Na9[EuW10O36] were fabricated. The composites were investigated by IR, UV,XRD, TGA, SEM and TEM. The prepared nanocomposites exhibit good superparamagnetic property and thermo-responsive switchable luminescence properties. The multifunctional nanocomposites can be separated by external magnetic field. Moreover, the nanocomposites exhibit an appreciable temperature response, and the red luminescence of the nanocomposites in solution can be controlled by the temperature stimuli. The hydrogel emits strong redluminescence in solution at 25 ℃,which can be seen by naked eyes. When the external temperature is 40 ℃, the red luminescence almost disappears in *** is expected that the multifunctional nanoparticles have potential applications in the field of biomedicine.

关键词： Magnetic Lanthanide Luminescence Thermosensitive controllable Rare carths

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