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Orthogonal design for optimization of pigment extraction from surface sediments of the Changjiang River Estuary

Acta Oceanologica Sinica 2011年第4期30卷 33-42页

作者： ZHAO Jun YAO Peng YU Zhigang Thomas S Bianchi key laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao 266100 China Department of Oceanography Texas A ＆ M University College Station TX 77843 USA key laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao 266100 China Institute of Marine Organic Geochemistry College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

Using a suitable solvent for extracting pigments from sediment for high performance liquid chromatography（HPLC） analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass,as well as community composition. Five methodological factors（sample dehydration,extraction solvent,extraction duration,number of extractions,and ratio of solvent volume：sample weight） were studied using an L 9（3 4 ） orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary（LDE）,using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L 9（3 4 ） orthogonal design experiments and showed that the extraction solvent was the most important,with extraction duration the second most important,and numbers of extraction and ratio of solvent volume：sample weight was the least important. The mixed solvent treatment comprised of acetone,methanol and water（80：15：5,by volume） was best for polar pigment extraction,with 100% acetone better for apolar pigments. For most pigments employed in this study（i.e.,peridinin,fucoxanthin,alloxanthin,diatoxanthin,zeaxanthin,pheophytin-a and β-carotene） ,3 h was found to be enough time for extraction from these deltaic sediments. However,for chlorophyll-a,the most important pigment used for estimating algal biomass,12 h was needed. A small amount of solvent（3 ml） with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately,no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study,taking into consideration the properties of sediments and pigments in question.

关键词： sedimentary pigments extraction orthogonal design HPLC Changjiang River Estuary

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Research on Ce-Zr compounds on modifying γ-alumina washcoat on FeCrAl foils

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Rare Metals 2005年第4期24卷 306-312页

作者： HUANG Ying SHEN Meiqing WANG Jun JIA Liwei key laboratory for Green chemical Technology of State education ministry School of Chemical Engineering ＆ Technology Tianjin UniversityTianjin 300072 China

Ce-Zr compounds such as Cc0.68Zr0.3202 solid solution, Ce/Zr nitrate and CeO2/ZrO2 were added into γ-alumina-based slurries, which were then loaded on FeCrAl foils pretreated at 950℃ and 1100℃. The microstructures and adhesion performance between the substrates and the washcoats were measured by SEM, BET surface area, ultrasonic vibration and thermal shock test. The results show that the addition of Ce0.68Zr0.32O2 solid solution, Ce/Zr nitrate and CeO2/ZrO2 into the slurries can improve γ-Al2O3-based washcoat adhesion on FeCrAl foils. Furthermore, ceria-zirconia solid solution increases the adhesion of the washcoat on the surface of an FeCrAl foil than the two others. The specific surface area of this washcoat remains about 4345 m^2/g and the weight loss is below 4.0% even after aging test of 10% steam-containing air at 1050℃ for 20 h.

关键词： chemical reaction engineering γ-alumina washcoat surface area Ce-Zr compounds metallic substrates

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Homologous and heterologous interactions between catalytic and regulatory subunits of Escherichia coli acetohydroxyacid synthaseⅠand Ⅲ

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Science china Chemistry 2009年第9期52卷 1362-1371页

作者： NIU CongWei, FENG Wei, ZHOU YanFei, WEN Xin & XI Zhen State key laboratory of Elemento-Organic Chemistry and Department of chemical biology, Nankai University, Tianjin 300071, china State key laboratory of Elemento-Organic Chemistry and Department of chemical biology Nankai University Tianjin China

Homologous and heterologous interactions between acetohydroxyacid synthase (AHAS) I and Ⅲ from E. coli have been studied by surface plasmon resonance (SPR). The catalytic and regulatory subunits association for AHAS I (KD = 1.13 × 10-7 M) was stronger than that for AHAS Ⅲ (KD = 5.29 × 10-7 M). A strong heterologous association between regulatory and catalytic subunits and heterologous activation of catalytic subunits were observed. SPR results combined with enzyme kinetics indicate that the reconstituted heterologous enzymes had similar kinetic properties as homologous enzymes, implying that the regulatory subunit of AHAS I could be replaced by the regulatory subunit of AHAS Ⅲ and vice versa. This work may be useful to further understandings of the mechanism of regulation of AHAS.

关键词： acetohydroxyacid synthase subunit interaction surface plasmon resonance

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Surface interrogation mode of scanning electrochemical microscopy for oxidation study of adsorbed CO generated from serine on platinum

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Chinese chemical Letters 2011年第12期22卷 1481-1484页

作者： Chun Cui Huang,Qian Wang,De Bo Xiang,Hui Bo Shao~* key laboratory of Cluster Science,ministry of education of china,School of Chemistry, Beijing Institute of Technology,Beijing 100081,china key laboratory of Cluster Science Ministry of Education of China School of Chemistry Beijing Institute of Technology Beijing 100081 China

We report a new method for detection and oxidation of adsorbed carbon monoxide(CO;) generated from serine on a polycrystalline platinum ultramicroelectrode（UME） by bromine（Br;） using in situ surface interrogation（SI） mode of scanning electrochemical microscopy（SECM）.In the SI mode,tip and substrate are both Pt UMEs,and CO;on Pt substrate,generated from serine,can be oxidized by the tip-generated Br;giving a positive *** CO;from serine instead of purging CO gas expands the newly introduced reaction of Br;with CO;and further enhances the hope to get rid of CO;on Pt for fuel cells.

关键词： SECM Surface interrogation mode Adsorbed carbon monoxide Serine Pt ultramicroelectrode

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Effect of Fly Ash and Early Strength Agent on Durability of Concrete Exposed to the Cyclic Sulfate Environment

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Journal of wuhan University of Technology(Materials Science) 2010年第6期25卷 1065-1069页

作者：袁晓露李北星 key laboratory of Silicate Materials Science and Engineering of ministry of education Wuhan University of Technology

The effect of fly ash and early strength agent on resistance of concrete to the cyclic sulfate environment was *** specimens made with ordinary portland cement or ordinary portland cement incorporating fly ash with the replacement of 10% or 20%,or 1% early strength agent and fly ash with the replacement of 20%,were made and subjected to 250 cycles of exposure to the cyclic sulfate *** properties including loss of mass,chloride ion diffusion coefficient,compressive strength and flexural strength were *** and chemical component of samples were determined by means of X-ray diffraction,scanning electron microscopy and energy dispersive *** experimental results indicated that effect of fly ash on the cyclic sulfate resistance of concretes was mostly dependent on the amount of fly *** strength agent improved performances of concrete with 20% fly ash exposed to cyclic sulfate environment.

关键词： fly ash early strength agent durability concrete cyclic sulfate environment

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Opportunity and challenge of target-based therapy for leukemia:lessons from APL and CML

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中国病理生理杂志 2010年第A10期26卷 1946-1947页

作者： CHEN Guo-qiang(Department of Pathophysiology,key laboratory of Cell Differentiation and Apoptosis of Chinese ministry of education & chemical biology Division of Shanghai Universities E-Institutes,Shanghai Jiaotong University School of Medicine,Shanghai 200025,china)

In the past two decades,target-based therapies achieve the great success in adult *** typical examples are the applications of all-trans retinoic acid(ATRA)/arsenic trioxide(ATO)and specific tyrosine kinase inhibitor imatinib respectively in acute promyelocytic leukemia(APL)and chronic myeloid leukemia(CML).These successful clinical practices originated from our understanding on

关键词： trioxide myeloid ATRA arsenic originated challenge granulocyte alterations targeting lymphoid

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Effect of copper addition on the thermal contraction of indium melt clusters

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Rare Metals 2003年第3期22卷 215-220页

作者： CHENGSujuan WANGZhonghua QINXubo BIANXiufang keylaboratoryofLiquidStructureandHeredityofMaterials MinistlyofEducationShandongUniversityJinan250061China ShandongDacahengpesticideCo.Ltd. Zibo255000.China

The structure of In-1 %Cu and In-5%Cu (mass fraction) alloy melts werestudied at different temperatures above liquidus by using a high-temperature X-ray diffractometerand were compared with that of pure In melt. Experimental results show that with the addition of 1%Cu or 5% Cu, the thermal contraction phenomenon of atom clusters occurs in melts with thetemperature increasing like pure In melt. With the addition of 1% Cu, the thermal contraction ofatom clusters increases and the contraction is not homogeneous in the whole measurement temperaturerange. The sudden change and noticeable contraction can be found in the range of 280-390 ℃. Thetemperature range of the sudden change is lower than that of pure In melt. With the addition of 5%Cu, the thermal contraction of atom clusters decreases and the contraction is not consistent in thewhole measurement temperature range. The anomalous change can be measured at about 600 ℃. At thesame superheating temperature, the nearest interatomic distance r_1 of the melts containing copperis smaller than that of pure In melt, implying that the cluster structure of melts containing copperis more compact.

关键词： liquid structure thermal contraction X-ray diffraction cluster copperaddition in melt

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Synthesis and photoluminescence property of red phosphors LiEu_(1-x)Y_x(WO_4)_(0.5)(MoO_4)_(1.5) for white LED

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Science china(Technological Sciences) 2009年第7期52卷 1913-1918页

作者： XIE An, YUAN XiMing, WANG JuanJuan & WANG Feng Engineering Research Center of Nano-Mineral Materials and Application, ministry of education, Faculty of Materials Science and chemical Engineering, china University of Geosciences, wuhan 430074, china Engineering Research Center of Nano-Mineral Materials and Application Ministry of Education Faculty of Materials Science and Chemical Engineering China University of Geosciences

A series of novel red phosphors LiEu1-xYx(WO4)0.5(MoO4)1.5 (x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.8) were synthesized by conventional solid state reaction method with the starting materials: WO3, MoO3, Eu2O3, Li2CO3 and Y2O3. The spectrum and the crystal structure of the phosphors were characterized by F-4500 and XRD respectively. Meanwhile the effects of flux and Y3+ concentration on the crystal structure and luminescent properties of the phosphors were investigated. The results showed that the optimal content of flux (WAlF3/WH3BO3=1/1) was 1 wt% and the optimal doping concentration of Y3+ was 0.5 mol. The emission spectrum showed the most intense peak was located at 615 nm, which corresponds to the 5D0→7F2 transition of Eu3+ and that Eu3+ occupied the lattice site of noncentrosymmetric environment in the scheelite phases. The excitation spectrum displayed that these phosphors could be effectively excited by ultraviolet (UV) (396 nm) and blue (466 nm) light, nicely in correspondence with the widely ap- plied output wavelengths of ultraviolet or blue LED chips. The influence of flux on the luminescent properties of LiEu0.5Y0.5(WO4)0.5(MoO4)1.5 phosphor was analyzed. The XRD spectra indicated that the flux could help to crystallize the phosphor, and no other phases were formed except the tetragonal. When adding flux, the relative intensity of LiEu0.5Y0.5(WO4)0.5(MoO4)1.5 became much stronger and the average particle size of the phosphor decreased.

关键词： red emitting phosphor LiEu1-xYx(WO4)0.5(MoO4)1.5 flux white LED

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Soil Organic Carbon,Carbon Fractions and Nutrients as Affected by Land Use in Semi-Arid Region of Loess Plateau of china

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Pedosphere 2010年第2期20卷 146-152页

作者： LIU Xun,LI Feng-Min,LIU Da-Qian and SUN Guo-Jun key laboratory of Arid and Grassland Ecology of the ministry of education,School of Life Sciences,Lanzhou University,Lanzhou 730000 (china) key laboratory of Arid and Grassland Ecology of the ministry of education School of Life Sciences Lanzhou University Lanzhou 730000 (China)

Cropland (CP),native grassland (NG) and two shrub land treatments which were converted from cropland in 1985:seabuckthorn (Hippophae rhamnoides L.) (ST),and branchytamarisk (Tamarix ramosissima) (BT) were investigated to evaluate effects of land use conversion on soil organic carbon (SOC) and soil nutrients in the semi-arid region of the Loess Plateau of *** organic carbon (TOC),light fraction organic carbon (LFOC),heavy fraction organic carbon (HFOC),total N (TN),nitrate nitrogen (NO 3-N) and nitrite nitrogen (NO 2-N),ammonium nitrogen (NH + 4-N),total P,and available P (AP) were *** results showed that SOC in NG,ST and BT were 12.7%,27.7% and 34.8% higher than that of the cropland,***,light fraction (LF) dry matter,ratio of TOC to TN (C/N) and the ratio of TOC to AP (C/P) were higher in the shrub land or native grassland than in the *** had the highest TN,the sum of NO 3-N and NO 2-N,TP and AP due to the use of chemical *** significantly correlated with LFOC,HFOC and C/*** significantly correlated with dry matter of the LF and C/***,the sum of NO 3-N and NO 2-N and AP were significantly negatively correlated with TOC and ***,land use conversion from cropland to shrub land,or maybe grassland,contributed to SOC sequestration and improved soil nutrients stabilization.

关键词： cropland heavy fraction organic carbon light fraction organic carbon native grassland shrub land

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Characterization and Comparison of Conducting Polyaniline Synthesized by Three Different Pathways

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Journal of wuhan University of Technology(Materials Science) 2011年第6期26卷 1068-1072页

作者：董超芳 Corrosion & Protection Center University of Science and Technology Beijing key laboratory for Corrosion and Protection of ministry of education

The conducting polyaniline （PANI） prepared by three chemical oxidative polymerization pathways including microemulsion, emulsion and aqueous solution methods were studied and compared. Their structures, morphologies and properties were characterized using FT-IR, XRD, TEM and TGA. PANI particles formed in aqueous solution have a smallest size and doping HCl enables to increase their conductivity. In contrast, PANI particles prepared by emulsion method have the highest thermal stability and conductivity and more ordered morphology. Rather different from these two methods, microemulsion approach allows forming nanocomposite PANI with tube-like nanostructure.

关键词： nano materials polymers polyaniline

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