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Photorheologically reversible micelle composed of polymerizable cationic surfactant and 4-phenylazo benzoic acid

Chinese Journal of Chemical Engineering 2016年第2期24卷 289-292页

作者： Jie Chen Bo Fang Hao Jin Licheng Yu Meng Tian Kejing Li Leiping Jin Mo Yang Shanghai Key laboratory of Multiphase Materials Chemical Engineering Lab of Chemical Engineering RheologyResearch Center of Chemical EngineeringEast China University of Science and Technology

A photorheologically reversible micelle composed of polymerizable cationic surfactant n-cetyl dimethylallyl am- monium chloride （CDAAC） and trans-4-phenylazo benzoic acid （trans-ACA） was prepared. The effects of molar ratio of CDAAC/trans-ACA, time of UV and visible light irradiation and temperature on the rheological properties of micellar system were investigated. The results show that before UV irradiation the system with an optimum CDAAC/trans-ACA molar ratio of 1.4 forms viscoelastic micelles at 45 ℃. After 365 nm UV irradiation, the viscos- ities of micelle systems with different concentrations at fixed molar ratio of 1.4 are decreased by 85%-95%. The CDAAC/trans-ACA （14 mmol. L- 1/10 mmol. L- 1 ） micelle system exhibits shear thinning property and its viscos- ity is decreased obviously with the increases of UV irradiation time less than I h. The rheological process during LIV irradiation for CDAAC/trans-ACA （14 mmol- L- 1/10 mmol. L 1） micelle proves that viscosity, elastic modulus G＇ and viscous modulus G＂ will reduce quickly with the UV light. Furthermore, the micelle system after 1 h UV- irradiation is able to revert to its initial high viscosity with 460 nm visible light irradiation for 4 h, and the micelle can be cycled between low and high viscosity states by repetitive UV and visible light irradiations. The LIV-Vis spectra of CDAAC/trans-ACA micelle indicate that its photosensitive theological properties are related closely to photoisomerization of trans-ACA to c/s-ACA.

关键词： Photorheological micelle Polymerizable cationic surfactant4-Phenylazo benzoic acid Rheological properties

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Two-photon absorption and frequency-upconversion properties of a new organic dye HMASPS

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Chinese Science Bulletin 2001年第14期46卷 1220-1223页

作者： Guangyong Zhou Yan Ren Chun Wang Dong Wang Xian Zhao Qi Fang Zongshu Shao Minhua Jiang Shandong Univ Inst Crystal Mat State Key Lab Crystal Mat Jinan 250100 Peoples R China

Two-photon absorption (TPA) and frequency-upconversion properties of a new upconversion laser dye trans-4-[p-(N-hydroxyethyl-N-methyl-amino)styryl]-N-meth-ylpyridinium toluene-p-sulfonate (abbreviated to HMASPS) were reported in this note. The linear absorption, TPA, single-photon induced fluorescence, TPA induced fluorescence and TPA induced upconverted lasing spectra of HMASPS solution in dimethyl formamide (abbreviated to DMF) were measured at room temperature. The red shift for the central wavelength of TPA induced fluorescence peak, which was compared with that of the single-photon induced fluorescence peak, and the blue shift for that of TPA induced up-converted lasing compared with that of TPA induced fluorescence, were explained by using re-absorption effect. TPA peak was at 930 nm. There is an 11 nm blue shift for two-photon energy of TPA peak compared with the linear absorption peak. The molecular TPA cross-section σ’2 at1064 nm was measured to be 6.0×10-48 cm4 .s/photon by using the open

关键词： organic dye HMASPS two-photon absorption fre- quency-upconverted lasing.

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Cloning and characterization of a delta-6 desaturase encoding gene from Nannochloropsis oculata

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Chinese Journal of Oceanology and Limnology 2011年第2期29卷 290-296页

作者：马晓磊俞建中朱葆华潘克厚潘瑾杨官品 lab of Applied Microalgae Biology the Key Laboratory of AquacultureMinistry of EducationOcean University of China College of Marine Life Sciences Ocean University of China

A gene （NANOC-D6D） encoding a desaturase that removes two hydrogen atoms from fatty acids at delta 6 position was isolated from a cDNA library of Nannochloropsis oculata （Droop） D. J. Hibberd （Eustigmatophyceae）. The unicellular marine microalga N. oculata synthesizes rich long chain polyunsaturated fatty acids （LCPUFAs）, including eicosapentaenoic acid （20：5n-3, EPA）. The deduced protein contains 474 amino acids that fold into 4 trans-membrane domains. The neighbor-joining phylogenetic tree indicates that NANOC-D6D is phylogenetically close to the delta-6 fatty acid desaturase of marine microalgae such as Glossomastix chrysoplasta, Thalassiosira pseudonana, and Phaeodactylum tricornutum. The gene was expressed in Saccharomyces cerevisiae INVScl to verify the substrate specificity of NAN OC-D6D. Our results suggest that the recombinant NANOC-D6D simultaneously desaturates linoleic acid （LA） and a-linolenic acid （ALA）.

关键词： microalgae Nannochloropsis oculata EPA delta-6 desaturase gene expression

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Induction of cranial and posterior trunk neural crest by exogenous retinoic acid in zebrafish

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Chinese Science Bulletin 2002年第13期47卷 1105-1108,1146页

作者： Ming Li Ying Su Anming Meng Tsing Hua Univ Dept Biol Sci & Biotechnol Prot Sci Lab MOE Beijing 100084 Peoples R China

Retinoic acid (RA) plays an important role in development of vertebrate embryos. We demonstrate impacts of exogenous RA on the formation of neural crest cells in zebrafish using specific neural crest markers sox9b and crestin. Treatment with all-trans RA at 10-7 mmol/L at 50% epiboly induces sox9b expression in the forebrain and crestin expression in the forebrain and midbrain, resulting in significant increase of pigment cells in the head derived from the cranial neural crest. In addition, RA treatment induces expression of sox9b and crestin in the caudal marginal cells of the neuroectoderm during early segmentation. Earlier commitment of these cells to the neural crest fate in the posterior margins leads to abnormal development of the posterior body, probably by preventing mingling of ventral derived and dorsal-derived cells during the formation of the tailbud.

关键词： zebrafish retinoic acid neural crest sox9b crestin.

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Mechanism Study of Rice Straw Pyrolysis by Fourier transform Infrared Technique

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Chinese Journal of Chemical Engineering 2009年第3期17卷 522-529页

作者：付鹏胡松向军孙路石杨涛张安超张军营 State Key lab of Coal Combustion Huazhong University of Science and Technology

The pyrolysis mechanism of rice straw (RS) was investigated using a tube reactor with Fourier trans-form infrared (FTIR) spectroscopy and thermogravimetric analyzer. The results show that the maximum pyrolysis rate increases with increasing heating rate and the corresponding temperature also increases. The three-pseudocomponent model could describe the pyrolysis behavior of rice straw accurately. The main pyrolysis gas products are H2O, CO2, CO, CH4, HCHO (formaldehyde), HCOOH (formic acid), CH3OH (methanol), C6H5OH (phenol), etc. The releasing of H2O, CO2, CO and CH4 mainly focuses at 220-400°C. The H2O formation process is separated into two stages corresponding to the evaporation of free water and the formation of primary volatiles. The release of CO2 first increases with increasing temperature and gets the maximum at 309°C. The releasing behavior of CO is similar to H2O and CO2 between 200 and 400°C. The production of CH4 happens, compared to CO2 and CO, at higher temperatures of 275-400°C with the maximum at 309°C. When the temperature exceeds 200°C, hy-droxyl and aliphatic C H groups decrease significantly, while C O, olefinic C C bonds and ether structures in-crease first in the chars and then the aromatic structure develops with rising temperature. Above 500°C, the material becomes increasingly more aromatic and the ether groups decreases with an increase of temperature. The aromati-zation process starts at ≈350°C and continues to higher temperatures.

关键词： rice straw pyrolysis mechanism Fourier transform intrared

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Phase regulated suppression and enhancement switches of four-wave mixing and fluorescence

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Frontiers of physics 2014年第2期9卷 153-156页

作者： Zhi-Guo Wang Peng Ying Pei-Ying Li Hua-Yan Lan He-Qing Huang Hao Tian Jian-Ping Song Yan-Peng Zhang Key laboratory for Physical Electronics and Devices of the Ministry of Education Shaanxi Key lab of Information Photonic Technique Xi'an Jiaotong University Xi'an 710049 China

We experimentally study the phase regulated switch between elcctromagnctically induced trans- parency and electromagmetically induced absorption in probe transmission signal and the conver- sion between enhancement and suppression in four-wave mixing and fluorescence signals for the first time. By changing the relative phase, electromagnetically induced transparency can be eonverted into electromagnetically induced absorption. In this process, the conversion from suppression to enhancement is also obtained in four-wave mixing and fluorescence signals. This research can be applied in non-linear optical device like optical switch and optical wavelength convertor.

关键词： four-wave mixing fluorescence phase regulation enhancement and suppression

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transformation toughening of Al_2O_3/ZrO_2 laminated ceramics with residual compressive stress

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Journal of University of Science and Technology Beijing 2007年第5期14卷 449-453页

作者： Bei Chen Chuan Cheng Lan Xiong Li-Ao Wang Key lab of High Voltage Engineering and Electrical New Technology Chongqing University Chongqing 400044 China Institute of Resource and Environment Science Chongqing University Chongqing 400044 China

With the help of scanning electronic microscopy and X-ray diffraction, the relationships of microstructure characteristics, phase assemblage, and fracture micrograph of Al2O3/ZrO2 laminated ceramics were studied. Compared with monolithic Al2O3/ZrO2 ceramics, the existence of surface compressive stresses greatly restrained the growth of ZrO2 and Al2O3 grains at high sinter temperature, fined the grain size, and increased the content of metastable t-ZrO2, which made the fracture transformation energy quantity 70% higher than that of the monolithic ceramics. The trans-granular and inter-granular fracture features were observed in the surface and center layers, which further verified that transformation toughening is the main mechanism, whereas, micro-crack toughening is helpful for enhancing fracture toughness.

关键词： laminated ceramics transformation toughening fracture micrograph grain size surface compressive stress

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Synthesis and Crystal Structure of [(NH_4)_6][Gd_2Mo_(36)O_(112)(H_2O)_(20)]·52H_2O

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Chinese Journal of Structural Chemistry 2001年第5期20卷 358-362页

作者：吴传德林祥等 State Key lab. of Struct. Chemistry Fujian Inst. Res. Struct. of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China

A novel compound [(NH_4)_6][Gd_2Mo_(36)O_(112)(H_2O)_(20)]·52H_2O (1) was obtained from the reaction of (NH_4)_6Mo7O24·4H_2O with GdCl3 at pH = 1.32. The X-ray structural analysis reveals that 1 crystallizes in monoclinic system, space group C2/c, Mr = 6937.77, a = 42.313(1), b=12.924(1), c=26.404(1) ?, β= 127.07(1)o, V=15086.2(6) ? 3, Z = 4, Dc = 2.976g·cm－3, ( = 3.316 mm－1, F(000) = 12963, the final R = 0.0585 and wR = 0.1490 for 5431 observed reflections. It contains a usual structural unit {Mo36}, which is linked to two eight-coordinated Gd3+ cations with the Gd-O distances from 2.31(5) to 2.46(5)

关键词： heteropolymolybdate polyoxoanion trans influence effect subunit

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Ancient deep roots for Mesozoic world-class gold deposits in the north China craton:An integrated genetic perspective

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Geoscience Frontiers 2020年第1期11卷 203-214页

作者： Cheng-Xue Yang M.Santosh School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Department of Earth Sciences University of AdelaideAdelaideSA 5005Australia Key lab of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Yonsei Frontier lab Yonsei UniversitySeoul 03722Republic of Korea

The North China Craton(NCC)hosts some of the world-class gold deposits that formed more than 2 billion years after the major orogenic cycles and *** diverse models for the genesis of these deposits remain equivocal,and mostly focused on the craton margin examples,although synchronous deposits formed in the interior *** we adopt an integrated geological and geophysical perspective to evaluate the possible factors that contributed to the formation of the major gold deposits in the *** the Archean tectonic framework of the NCC,the locations of the major gold deposits fall within or adjacent to greenstone belts or the margins of *** the Paleoproterozoic framework,they are markedly aligned along two major collisional sutures-the trans North China Orogen and the Jiao-Liao-Ji *** the Mesozoic intrusions hosting these deposits do not carry adequate signals for the source of gold,we explore the deep roots based on available geophysical *** show that the gold deposits are preferentially distributed above zones of uplifted MOHO and shallow lab corresponding to thinned crust and eroded sub-lithospheric mantle,and that the mineralization is located above regions of high heat flow representing mantle *** NCC was at the center of a multi-convergent regime during the Mesozoic which intensely churned the mantle and significantly en riched *** geophysical data on Moho and lab upwarp from the centre towards east of the craton is more consistent with paleo-Pacific slab subduction from the east exerting the dominant control on lithospheric *** on these results,and together with an evaluation of the geochemical and isotopic features of the Mesozoic magmatic intrusions hosting the gold mineralization,we propose a genetic model that invokes reworking of ancient Au archives preserved in the lower crust and metasomatised upper mantle and which were generated through multiple subduction,underplating and cumulation ev

关键词： Gold metallogeny Subduction tectonics Lithospheric thinning Mantle metasomatism North China craton

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Global pollution shown by lead and cadmium contents in precipitation of polar regions and Qinghai-Tibetan Plateau

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Chinese Science Bulletin 2000年第9期45卷 847-853页

作者： Cunde Xiao Dahe Qin Tandong Yao Jiawen Ren Yuefang Li Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lab Ice Core & Cold Reg Environm Lanzhou 730000 Peoples R China

The analysis of the major ions, lead and cadmium has been performed for snow-pit samples collected from the Arctic, the Qinghai-Tibetan Plateau and the Antarctic Ice Sheet. These snow pits were excavated respectively from the snowpack in Canadian Northwest Territory (NWT) and the central Arctic, three glaciers on the Qinghai-Tibetan Plateau and surface snow along the route of the International trans-Antarctic Expedition (ITAE). The source regions for the lead pollution of central Arctic have been identified by analyzing of stable lead isotopic ratios, meteorological and atmospheric chemistry studies. It shows that the central Arctic is still under intensive lead input, despite the fact that lead content in Greenland Ice Sheet displays a rapid decreasing since the 1970s due to US and some European countries’ campaigns to reduce lead-containing gasoline-additives. This is because there are multiple lead sources for the central Arctic, including the countries that have not performed gasoline-additives

关键词： key regions of cryosphere heavy metals global pollution.

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