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Spatial variability of summertime aragonite saturation states and its influencing factor in the Bering Sea

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Advances in Climate Change Research 2021年第4期12卷 508-516页

作者： sun Heng GAO Zhong-Yong ZHAO De-Rong sun xiu-Wu CHEN Li-Qi Key Laboratory of Global Change and Marine-Atmospheric Chemistry(GCMAC)of Ministry of Natural Resources(MNR) Third Institute of Oceanography(TIO)MNRXiamen361005China

The Bering sea is susceptible to ocean acidification driven by both human activities(anthropogenic CO_(2))and distinctive natural *** assess the situation of ocean acidification,we investigated the spatial variability of aragonite saturation states(ΩAr)in July 2010 during the 4th Chinese National Arctic Research Expedition(CHINARE).The surface waters were all oversaturated with respect to aragonite(ΩAr>1)due to high biological removal,andΩAr ranged from 1.43 to *** relatively lowΩAr values were found in the western Bering Strait and eastern nearshore region of the Bering Sea Shelf,which were associated with the upwelling and riverine input,*** the subsurface,theΩAr decreased to generally low saturation states and were observed to be strongly undersaturated(ΩAr<1)in the bottom waters with a lowest value of 0.45,which might be caused by ***,unlike prior studies,the lowΩAr values in the shallow nearshore region were still above the saturation horizon throughout the water column,which were probably counteracted by high local primary *** the context of climate change and increasing anthropogenic CO_(2)absorption,the suppression and undersaturation ofΩAr in the Bering Sea are not only attributed to the natural processes but also the accumulation of anthropogenic CO_(2).

关键词： Bering sea Ocean acidification Aragonite saturation states Spatial variability Controls

Synthesis and characterization of titanium complexes bearing sulfoxide groups and their catalytic behaviors in ethylene homo- and copolymerization

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Science China Chemistry 2014年第8期57卷 1144-1149页

作者： WANG Zheng PENG Ai-Qing sun xiu-Li TANG Yong State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

Titanium complexes derived from 2,4-di-tert-butyl-6-（（2-（arylsulfinyl）phenylimino）methyl）phenol are designed and synthe- sized. X-ray diffraction studies reveal that the complexes adopt distorted octahedral geometry with O（phenol）, N（imine）, and O（sulfoxide） coordinated with titanium. Combined with modified methylaluminoxane（MMAO）, the complexes exhibit moderate to high activity to afford polyethylene even at 120 ℃ under 1 atm ethylene pressure. The complexes also show excellent capability in copolymerization of ethylene with either 1-hexene or norbornene. Results indicate that the introduction of sulfoxide groups could open the space around central metal and favors the insertion of bulky comonomers.

关键词： sulfoxide catalyst synthesis ethylene polymerization copolymerization

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Frequency Selective Propagation by Employing Fabry-Perot Nanocavities in a Subwavelength Double-slit Structure

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Chinese Physics Letters 2012年第4期29卷 217-220页

作者： M.Afshari Bavil sun xiu-Dong HUANG Feng Optical Information Processing Group Department of PhysicsHarbin Institute of TechnologyHarbin 150001

By embedding a nanocavity adjacent to one or both of slits in a subwavelength double-slit structure,frequency selective propagation through the slits is *** the incident light wavelength corresponds to the cavity resonance mode,the electromagnetic wave passing through the slit will be trapped within the ***,the double slit operates as a single slit and light propagation is solely allowed through the partner *** wavelengths are determined by applying the Fabry Perot resonance condition for the *** geometrical structures result in different effective refractive ***,the effective refractive index and consequently the attenuation wavelength can be adjusted by choosing the appropriate parameters of the *** theoretical predictions are in good agreement with 2D finite-difference time-domain simulation.

关键词： refractive cavity double

Isolation and Characterization of a Bioactive Polysaccharide from Panax Quinquefolium L.

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Chemical Research in Chinese Universities 1998年第2期14卷 35-38页

作者： MA xiu-li HAO Chun-yan LU Shi-xiang sun Yun-xiu LIU Ju-zheng LIU Shu-ying Department of Chemistry Jilin UniversityChangchun130023 Changchun Institute of Applied Chemistry Changchun130022

ＩｓｏｌａｔｉｏｎａｎｄＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆａＢｉｏａｃｔｉｖｅＰｏｌｙｓａｃｃｈａｒｉｄｅｆｒｏｍＰａｎａｘＱｕｉｎｑｕｅｆｏｌｉｕｍＬ．ＭＡＸｉｕ－ｌｉ＊，ＨＡＯＣｈｕｎ－ｙａｎ，ＬＵＳｈｉ－ｘ... 详细信息

ＩｓｏｌａｔｉｏｎａｎｄＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆａＢｉｏａｃｔｉｖｅＰｏｌｙｓａｃｃｈａｒｉｄｅｆｒｏｍＰａｎａｘＱｕｉｎｑｕｅｆｏｌｉｕｍＬ．ＭＡＸｉｕ－ｌｉ＊，ＨＡＯＣｈｕｎ－ｙａｎ，ＬＵＳｈｉ－ｘｉａｎｇ，ＳＵＮＹｕｎ－ｘｉｕ，Ｌ...

关键词： Panax quinquefolium L. Polysaccharide Matrixassisted laser desorption/ionization mass spectrometry(MALDIMS)

Analysis on Genetic Diversity and Genetic Basis of the Main Sesame Cultivars Released in China

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Agricultural Sciences in China 2011年第4期10卷 509-518页

作者： ZHANG Yan-xin sun Jian ZHANG xiu-rong WANG Lin-hai CHE Zhuo Oil Crop Research Institute Chinese Aeademy of Agrieultural Sciences~Key Laboratory of Oil Crop Biology Ministry of Agriculture Wuhan430062 P.R. China

SRAP （sequence-related amplified polymorphism） was used for the analysis of 67 sesame （Sesamum indicum L.） cultivars widely used in Chinese sesame major production areas from 1950 to 2007. A total of 561 bands were amplified using 21 SRAP random primer pairs, with 265 of them were polymorphic, resulting in a polymorphism ratio of 47.2%. The total bands and polymorphism amplified by each primer pair averaged 26.7 and 12.6, respectively. The average genetic similar coefficient and genetic distance of the 67 cultivars were 0.9104 and 0.0706, respectively, indicating limited genetic diversity and narrow genetic basis. Comparative analysis on genetic similarity and genetic distance of different classified cultivars showed that the difference of average genetic similarity coefficient and genetic distance between the landraces and cultivars bred through crosses reached significant levels （P=0.01）, with the genetic basis of landraces wider than that bred cultivars. The genetic basis of cultivars used in 1990-2007 was more narrow than that of cultivars from 1950 to 1969 and from 1970 to 1989, with the differences of average genetic similarity coefficient and genetic distance reached 0.01 significant level. The genetic basis of Chinese sesame main cultivars is relatively narrow, and the genetic basis of cultivars developed through crosses in recent years is narrower than history cultivars.

关键词： sesame (Sesamum indicum L.) cultivars SRAP genetic diversity genetic basis

Synthesis and Characterization of Layered Co_2(OH)_3(CH_3COO)·H_2O

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Chemical Research in Chinese Universities 2011年第6期27卷 910-914页

作者： ZHENG De-shan WANG Yan-zhong SHI Li-min sun Si-xiu School of Materials and Chemical Engineering Xi＇an Technological University Xi＇an 710032 P. R. China School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China

Layered hydroxide metal acetate Co2（OH）3（CH3COO）·H2O with an interlayer spacing of 1.282 nm has been synthesized by a novel method which is employed in ethanol-aqueous mixed solvents media. Experiment results show that the purity of the product by the modified method is higher compared with that by the previous methods. A complete characterization of the as-prepared samples was performed by means of X-ray powder diffraction, IR spectroscopy, scanning electron microscope, as well as magnetic measurement. The facile and effective approach for the preparation of this compound in this study is very interesting and important because it has wide application in the field of anionic exchange reaction for the synthesis of hybrid organic-inorganic compounds.

关键词： Anionic exchange reaction Hybrid organic-inorganic compound Layered hydroxide cobalt acetate Magnetic property

Lamb wave signal selective enhancement by an improved design of meander-coil electromagnetic acoustic transducer

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Chinese Physics B 2018年第8期27卷 308-314页

作者： Wen-xiu sun Guo-Qiang Liu Hui Xla Zheng-Wu Xia Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 101408China

In this paper, we investigate a method of selectively enhancing the single mode signal of a Lamb wave by using a meander-coil electromagnetic acoustic transducer （EMAT） with a new magnetic configuration. We use the Lamb antisym- metric （A0） mode and symmetric （SO） mode as an example for analysis. The analytical expression of the magnitude of the spatial Fourier transform of the Lorentz force generated by different meander coils is used to determine the optimal driving frequency for single mode generation. The numerical calculation is used to characterize the new magnetic configuration and the conventional EMAT magnet. Experimental examinations of each meander coil in combination with the conventional and new magnetic configuration show that the Lamb wave signal can be selectively enhanced by choosing the appropriate driving frequency and coil parameters through using the improved meander-coil EMAT.

关键词： Lamb wave selective enhancement meander-coil electromagnetic acoustic transducer (EMAT)

Effects of Main Parameters on Rheological Properties of Oil-Coal Slurry

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Journal of China University of Mining and Technology 2006年第3期16卷 274-277页

作者： WANG Yong-gang HAO Li-fang XIONG Chu-an sun xiu-ying School of Chemical and Environmental Engineering China University of Mining ＆ Technology Beijing 100083 China School of Resource and Environmental Engineering Heilongjiang Institute of Science and Technology Harbin Heilongjiang 150027 China

Oil-coal slurry prepared in coal direct liquefaction is a dispersed solid-liquid suspension system. In this paper, some factors such as solvent properties, solid concentrations and temperatures, which affect viscosity change of oil-coal slurry, were studied. The viscosity of coal slurry was measured using rotary viscometer, and the rheological properties have been investigated. The viscosity and rheological curves were plotted and regressed, respectively. The results show that the coal slurry behaves a pseudoplastic and thixotropic property. The rheological type of coal slurry was ascertained and its rheological equations were educed. The oil-coal slurry changes to non-Newtonian fluid from Newtonian fluid with the increasing of solid concentration.

关键词： direct liquefaction oil-coal slurry rheological property optimized regression

Hydrothermal Synthesis and Luminescent Properties of Flowerlike Zn_2GeO_4 and Mn^(2+)-Doped Zn_2GeO_4 Hierarchical Architectures

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Chemical Research in Chinese Universities 2012年第5期28卷 764-767页

作者： LI Bo SONG Shu-yan sun xiu-juan PENG Jing WANG Bo XING Yan College of Chemistry Northeast Normal UniversityChangchun 130024P.R.China State Key Laboratory of Rare Earth Resource Utilizations Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

Three-dimensional（3D） flowerlike hierarchical Zn2GeO4 and Mn2＋-doped Zn2GeO4 microstructures have been prepared by a facile hydrothermal approach. X-Ray diffraction（XRD）, field emission scanning electron micro-scopy（FESEM）, transmission electron microscopy（TEM） and photoluminescence（PL） spectrometry were employed to characterize the samples. Such flowerlike hierarchical Zn2GeO4 microstructures with an average diameter of 3―4 μm were found to be constructed by abundant single crystalline nanorods of about 90 nm in diameter. The luminescent properties of Zn2GeO4：xMn phosphors with different contents of Mn2＋ as an activator were investigated. The Mn2＋-doped samples showed green luminescence corresponding to the d-d transition of Mn2＋ under the irradiation of UV light. The red shift（from 531 nm to 538 nm） in λem with increasing Mn2＋ content was observed in the luminescent spectra, which should be attributed to a weak crystal field because of the substitution of Zn2＋ by Mn2＋ at a distorted tetrahedral lattice site.

关键词： Zinc orthogermanate Hierarchical architecture Luminescent property