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Redox-active Ferrocene-dithiolenes Hybrid Complexes Showing Switchable Nonlinear Optical Properties

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Chemical Research in Chinese Universities 2015年第5期31卷 792-796页

作者： YU Hailing HONG Bo zhao Hongyan College of Resources and Environmental Sciences Jilin Agricultural University Changchun 130118 P R. China State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration Northeast Normal University Changchun 130024 P R. China

Density functional theory（DFT） calculations were carried out to investigate the geometry structures, redox properties and second-order nonlinear optical（NLO） properties of ferrocene（Fc）-dithiolenes hybrid complexes. The switchable second-order NLO properties of these complexes are induced by the redox process. The oxidized process significantly affects the geometrical structures of the dithiolene moieties, that is, the embowed dithiolene moieties change into planar structures. It supports that the dithiolene moieties are the oxidized center. The βtot values of the cationic species are at least 4 and 10 times those of their corresponding parent complexes, respectively. Further, the time-dependent DFT calculation illustrates that the low-energy absorption（which is helpful for the large NLO response） is mainly assigned to intra-ligand charge transfer [π（ex-dithiolene）→π（ex-dithiolene）]. These results suggest the potential use of the novel Fc-based dithiolenes complexes as versatile and fascinating NLO switching materials.

关键词： Dithiolene Redox Nonlinear optical Molecular switching Density functional theory

Grafting of Poly（lauryl acrylate） onto Nano-silica by ‘Click Chemistry’

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Chemical Research in Chinese Universities 2014年第2期30卷 339-342页

作者： CHEN Kailing zhao Yunhui YUAN Xiaoyan Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and Engineering Tianjin University Tianjin 300072 P.R.China

Poly（n-alkyl acrylate） with long side groups,namely,poly（lauryl acrylate）（PLA） was synthesized by reversible addition-fragmentation chain transfer（RAFT） polymerization,and the trithioester terminal groups were converted to thiol by reducing *** of the obtained polymer onto nano-silica modified with 3-（methacryloxy）propyl-trimethoxysilane（SiO2-MPS） was conducted by thiol-ene ‘click chemistry＇.PLA was characterized by proton nuclear magnetic resonance（1H NMR） and gel permeation chromatography（GPC）.Fourier transform infrared（FTIR） spectrometry and thermogravimetric analysis（TGA） were used to demonstrate the grafting reaction,and the grafted hairy nano-silica（SiO2-g-PLA） was viewed under a transmission electron microscope（TEM）.According to TGA,grafting ratio and grafting density of SiO2-g-PLA are 30.27％ and 0.013 chain/nm2,*** static water contact angle of SiO2-g-PLA is （80.10±2.97）°,which ensures its *** experiment was carried out to confirm its dispersibility in mixed solvents,indicating its potential application in coatings or composites.

关键词： ‘Click chemistry’ Grafting Poly(lauryl acrylate) Nano-silica Dispersibility

Transition State Theory Rate in Nonlinear Environment： the Under-damping Case

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Communications in Theoretical Physics 2005年第4X期44卷 752-756页

作者： zhao Jiang-Lin BAO Jing-Dong Physics Department Beijing Normal University Beijing 100875 China

We investigate the escape behavior of systems governed by the one-dimensional nonlinear Kramers＇ equation δW/δt = -vδW/δx ＋（f＇（x）/m）（δW/δv）＋ γδ（vW）/δv ＋（γκBT/m）（δ2W^μ/δv^2）, where f（x） is a metastable potential and μ an anomalous exponent. We obtain an expression for the transition state theory escape rate, whose predictions are in good agreement with numerical simulations. The results exhibit the anomalies due to the nonlinearity in W that the TST rate grows with T and drops as μbecomes large at a fixed T. Indeed, particles in the subdiffusive media （μ 〉 1） can escape over the barrier only when T is above a critical value, while there does not exist this confinement in the superdiffusive media （μ 〈 1）.

关键词： Kramers' escape rate nonlinear Fokker-Planck equation anomalous diffusion

Special issue： Nanotechnology in energy

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Frontiers in Energy 2018年第1期12卷 1-4页

作者： Changying zhao Zhuomin ZHANG Xing ZHANG Institute of Engineering Thermophysics Shanghai Jiao Tong UniversityShanghai 200240 China George W. Woodruff School of Mechanical Engineering GeorgiaInstitute of Technology Atlanta GA 30332 USA Key Laboratory for Thermal Science and Power Engineering of Ministryof Education Department of Engineering Mechanics TsinghuaUniversity Beijing 100084 China

Nanostructured materials exhibit exotic properties for thermal transport and storage as well as light absorption. The aim of this special issue is to provide a small collection from a large field of nanotechnology related to energy applications. Nano/microscale heat and mass transfer plays an important role in emerging energy systems and thermal management.

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Direct estimation of the Solar acceleration using geodetic/astrometric VLBI observations

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Science China(Physics,Mechanics & Astronomy) 2012年第2期55卷 329-332页

作者： XU MingHui WANG GuangLi zhao Ming Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The secular aberration drift observed as the apparent proper motion of extragalactic radio sources is caused by the acceleration of the coordinate origin,the Solar System ***,the acceleration can be estimated as a global parameter by using the 30 years global geodetic/astrometric VLBI *** estimation is independent of any kinematic or dynamic model of the Milky Way or statistics *** estimated acceleration in the direction of the Galactic center is (0.80±0.04) cm·s-1 ·yr-1,while the other two components are (0.0-1±0.06) and (0.52±0.05) cm ·s-1 ·yr-1 in the direction along the Solar motion in the Galactic plane and in the direction normal to the Galactic plane,*** estimate of the acceleration independently provides another kinematics parameter without referring to any objects within the Galaxy.

关键词： solar acceleration secular aberration VLBI astrometry

Double-peaked decay of transient photovoltage in nanoporous ZnO/n-Si photodetector

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Science China(Physics,Mechanics & Astronomy) 2014年第6期57卷 1206-1208页

作者： LIU Hao FU Cheng zhao Kun State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Key Laboratory of Oil and Gas Terahertz Spectroscopy and Photoelectric Detection China Petroleum and Chemical Industry Federation(CPCIF)

In the present work,a nanoporous ZnO/n-Si structure has been proposed as a new type infrared *** by one laser pulse with wavelength of 1064 nm,this structure exhibits a double-peak decay of transient ***,the time interval between these two peaks increases linearly with the increase of irradiated pulsed energy,indicating the promising application of this hetero-junction in photo-energy detection of infrared pulsed laser.A possible mechanism for this particular photoresponse has been discussed.

关键词： ZnO sol-gel photovoltage photodetector

Overexpression of IbSnRK1 enhances nitrogen uptake and carbon assimilation in transgenic sweetpotato

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Journal of Integrative Agriculture 2018年第2期17卷 296-305页

作者： REN Zhi-tong zhao Hong-yuan HE Shao-zhen ZHAI Hong zhao Ning LIU Qing-chang Key Laboratory of Sweetpotato Biology and Biotechnology Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis and Utilization Ministry of Education/China Agricultural University

Nitrogen is an important nutrient for plant development. Nitrogen and carbon metabolisms are tightly linked to physiological functions in plants. In this study, we found that the IbSnRK1 gene was induced by Ca（NO3）2. Its overexpression enhanced nitrogen uptake and carbon assimilation in transgenic sweetpotato. After Ca（^15NO3）2 treatment, the -（15）N atom excess, -（15）N and total N content and nitrogen uptake efficiency（NUE） were significantly increased in the roots, stems, and leaves of transgenic plants compared with wild type（WT） and empty vector control（VC）. After Ca（NO3）2 treatment, the increased nitrate N content, nitrate reductase（NR） activity, free amino acid content, and soluble protein content were found in the roots or leaves of transgenic plants. The photosynthesis and carbon assimilation were enhanced. These results suggest that the IbSnRK1 gene play a important role in nitrogen uptake and carbon assimilation of sweetpotato. This gene has the potential to be used for improving the yield and quality of sweetpotato.

关键词： carbon assimilation IbSnRK1 nitrogen uptake sweetpotato

A New Method for the Synthesis of C/D Ring Synthon of Vitamin D

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Chinese Chemical Letters 1998年第3期9卷 259-260页

作者： Gao, LJ zhao, TZ Han, GD Henan Acad Sci Inst Chem Zhengzhou 450003 Peoples R China Chinese Acad Med Sci Inst Mat Med Peking Union Med Coll Beijing 100050 Peoples R China

A C/D ring synthon of vitamin D is readily obtained from cholesteryl acetate via oxidation, elimination of acetoxy group and Norrish type II photochemical reaction.

关键词： C/D ring synthon vitamin D cholesteryl acetate photochemical degradation

Kalman filtering-based supervisory run-to-run control method for semiconductor diffusion processes

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Science China(Information Sciences) 2019年第8期62卷 198-200页

作者： zhao XU Changhua HU Jinwen HU School of Electronics and Information Northwestern Polytechnical University Xi'an Research Institute of High-Technology School of Automation Northwestern Polytechnical University

Dear editor,In response to the need for continuous tuning solutions in run-to-run (R2R) manufacturing processes, R2R control began to emerge in academic and industrial research two decades ago. It is aimed at minimizing process drift, shift and variability between machine runs and decreasing cost in semiconductor companies. However, gaps still exist between the current development of R2R technologies and their industry-wide commercial-

关键词： Kalman filtering-based supervisory run-to-run control method for semiconductor diffusion processes pro