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Chinese Chemical Letters 2001年第4期12卷 293-296页

作者： Zhao Yang WANG Jia Ling CUI Bao Shan DU Qing Hua CHEN Department of Chemistry Beijing Normal UniversityBeijing 100875 Dept.of Chem. South China Nor.UnivGuangzhou 510631 present address:School of Pharm. Beijing UnivBeijing 100033

1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of prepar... 详细信息

关键词： Michael addition Grignard reagent 1 3-dipolar cycloaddition silyl nitronates.

Synthesis of Monodisperse Poly(glycidylmethacrylate-coethylene dimethacrylate) Beads and Their Application in Separation of Biopolymers

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Chinese Journal of Chemistry 2004年第3期22卷 283-289页

作者：龚波林柯从玉耿信笃 present address:Key Laboratory of Energy & Chemical engineering Ningxia UniversityYinchuan 750021China Institute of Modern Separation Science Key Laboratory of Modern Separation Science in Shaanxi Province Northwest University Xi'an Shaanxi 710069 China

The monodisperse poly(glycidyl methacrylate-co-ethylene dimethacrylate) beads with macroporous in the range of 8.0—12.0 m were prepared by a single-step swelling and polymerization method. The seed particles prepared by dispersion polymerization exhibited good absorption of the monomer phase. The pore size distribution of the beads was evaluated by gel permeation chromatography and mercury intrusion method. By using this media, a weak cation exchange (WCX) stationary phase for HPLC was synthesized by a new chemical modification method. The prepared resin has advantages of biopolymer separation, high column efficiency, low column backpressure, high protein mass recovery and good resolution for proteins. The measured bioactivity recovery for lysozyme was (96±5)%. The dynamic protein loading capacity of the synthesized WCX packings was 21.3 mg/g. Five proteins were completely separated in 8.0 min using the synthesized WCX stationary phase. The experimental results show that the obtained WCX resin has very weak hydrophobicity. The WCX resin was also used for the rapid separation and purification of lysozyme from egg white in 8 min with only one step . The purity and specific bioactivity of the purified lysozyme was found more than 92.0% and 70184 U/mg, respectively.

关键词： monodisperse poly(glycidyl methacrylate-co-ethylene dimethacrylate) resins weak cation exchange chromatography protein separation egg white

Optical actuation of a micromechanical photodiode via the photovoltaic-piezoelectric effect

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Microsystems & Nanoengineering 2021年第2期7卷 167-175页

作者： A.Rampal R.N.Kleiman Department of Engineering Physics McMaster UniversityHamiltonONL8S 4L7Canada present address:CircuitMind Inc 185 Spadina AvenueTorontoONM5T 2C6Canada

Radiation pressure and photothermal forces have been previously used to optically actuate micro/nanomechanical structures fabricated from semiconductor piezoelectric materials such as gallium arsenide(GaAs).In these materials,coupling of the photovoltaic and piezoelectric properties has not been fully explored and leads to a new type of optical actuation that we call the photovoltaic-piezoelectric effect(PVPZ).We demonstrate this effect by electrically measuring,via the direct piezoelectric effect,the optically induced strain in a novel torsional *** micron-scale torsional resonator is fabricated from a lattice-matched single-crystal molecular beam epitaxy(MBE)-grown GaAs photodiode *** find that the strain depends on the product of the electro-optic responsivity and piezoelectric constant of *** photovoltaic-piezoelectric effect has important potential applications,such as in the development of configurable optical circuits,which can be used in neuromorphic photonic chips,processing of big data with deep learning and the development of quantum circuits.

关键词： resonator piezoelectric effect

Experimental and modeling study of wettability alteration through seawater injection in limestone:a case study

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Petroleum Science 2020年第3期17卷 749-758页

作者： Omolbanin Seiedi Mohammad Zahedzadeh Emad Roayaei Morteza Aminnaji Hossein Fazeli Improved Oil Recovery Institute.National Iranian Oil Company(NIOC) Tehran ***Iran Institute of Petroleum Engineering University of TehranP.O.Box 11155-4563TehranIran present address:Sharif Upstream Petroleum Research Institute(SUPRI) Sharif University of TechnologyTehranIran present address:Research Institute of Petroleum Industry(RIPI) TehranIran School of Chemical Engineering and Analytical Science University of ManchesterManchesterUK Geochemistry Research Group University of NottinghamUniversity ParkNottinghamUK

Water flooding is widely applied for pressure maintenance or increasing the oil recovery of *** heterogeneity and wettability of formation rocks strongly affect the oil recovery efficiency in carbonate *** seawater injection in carbonate formations,the interactions between potential seawater ions and the carbonate rock at a high temperature can alter the wettability to a more water-wet *** paper studies the wettability of one of the Iranian carbonate reservoirs which has been under Persian Gulf seawater injection for more than 10 *** wettability of the rock is determined by indirect contact angle measurement using Rise in Core ***,the characterization of the rock surface is evaluated by molecular kinetic theory(MKT)*** data obtained from experiments show that rocks are undergoing neutral wetting after the aging *** the wettability of low permeable samples changes to be slightly water-wet,the wettability of the samples with higher permeability remains unchanged after soaking in *** data and MKT analysis indicate that wettability alteration of these carbonate rocks through prolonged seawater injection might be insignificant.

关键词： Wettability Carbonate rock Seawater injection Dynamic contact angle Rise in Core Molecular kinetic theory

Structure and evolution of the continental margin off Norway and the Barents Sea

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Episodes 2008年第1期31卷 82-91页

作者： Jan Inge Faleide Filippos Tsikalas AsbjФrn Breivik Rolf Mjelde Oliver Ritzmann Фyvind Engen Jonas Wilson Olav Eldholm Department of Geosciences University of Oslo P.O. Box 1047 Blindem N-0316 Oslo Norway. Department of Earth Science University of Bergen Allegaten 41 N-5007 Bergen Norway. present address： Eni Norge AS P.O. Box 101 Forus N-4064 Stavanger Norway. present address： StatoilHydro N-0246 Oslo Norway.

The Norwegian Margin formed in response to early Cenozoic continental breakup and subsequent opening of the Norwegian-Greenland Sea. There is a welldefined margin segmentation and the various segments are characterized by distinct crustal properties, structural and magmatic styles, and post-opening history of vertical motions. The sedimentary basins at the conjugate continental margins off Norway and Greenland and in the western Barents Sea developed as a result of a series of post-Caledonian rift episodes until early Cenozoic time, when complete continental separation took place.

关键词：大陆边界地质构造巴伦支海挪威

Gold Nanozymes:From Concept to Biomedical Applications

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Nano-Micro Letters 2021年第1期13卷 138-173页

作者： Javier Lou‑Franco Bhaskar Das Christopher Elliott Cuong Cao Institute for Global Food Security School of Biological SciencesQueen’s University of Belfast19 Chlorine GardensBelfast BT95DLUK present address:Department of Biotechnology and Medical Engineering National Institute of Technology RourkelaRourkelaIndia

In recent years,gold nanoparticles have demonstrated excellent enzyme-mimicking activities which resemble those of peroxidase,oxidase,catalase,superoxide dismutase or ***,merged with their ease of synthesis,tunability,biocompatibility and low cost,makes them excellent candidates when compared with biological enzymes for applications in biomedicine or biochemical ***,over 200 research papers have been systematically reviewed to present the recent progress on the fundamentals of gold nanozymes and their potential *** review reveals that the morphology and surface chemistry of the nanoparticles play an important role in their catalytic properties,as well as external parameters such as pH or ***,real applications often require specific biorecognition elements to be immobilized onto the nanozymes,leading to unexpected positive or negative effects on their ***,rational design of efficient nanozymes remains a challenge of paramount *** implementation paths have already been explored,including the application of peroxidase-like nanozymes for the development of clinical diagnostics or the regulation of oxidative stress within cells via their catalase and superoxide dismutase *** review also indicates that it is essential to understand how external parameters may boost or inhibit each of these activities,as more than one of them could ***,further toxicity studies are required to ensure the applicability of gold nanozymes in *** challenges and future prospects of gold nanozymes are discussed in this review,whose significance can be anticipated in a diverse range of fields beyond biomedicine,such as food safety,environmental analyses or the chemical industry.

关键词： Gold nanoparticles Catalysis Nanozymes Diagnosis Nanomedicine

The Arabidopsis thaliana RNA Editing FactorSLO2, which Affects the Mitochondrial ElectronTransport Chain, Participates in Multiple Stressand Hormone Resoonses

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Molecular Plant 2014年第2期7卷 290-310页

作者： Qiang Zhu Jasper Dugardeyn Chunyi Zhang Per Mühlenbock Peter J. Eastmond Roland Valcke Barbara De Coninck Sevgi Öden Michael Karampelias Bruno P.A. Cammue Els Prinsen Dominique Van Der Straeten Laboratory of Functional Plant Biology Department of Physiology Ghent University K.L. Ledeganckstraat 35 B-9000 Ghent Belgium present address: Milieudienst Midden West-Vlaanderen Peter Benoitstraat 13 8800 Roeselare Belgium present address: Biotechnology Research Ins. Chinese Academy of Agricultural Sciences 12 ZhongGuanCun NanDajie Haidian District Beijing 100081 PR China present address: Department of Plant Protection Biology Swedish University of Agricultural Sciences Sundsvägen 14 Sweden Department of Plant Biology and Crop Science Rothamsted Research Harpenden AL5 2JQ UK Molecular and Physical Plant Physiology Faculty of Sciences Hasselt University Bldg. D Agoralaan B-3590 Diepenbeek Limburg Belgium Centre of Microbial and Plant Genetics (CMPG) Katholieke Universiteit Leuven Kasteelpark Arenberg 20 B-3001 Heverlee Belgium Department of Biology University of Antwerp Groenenborgerlaan 171 B-2020 Antwerpen Belgium present address: Department of Plant Systems Biology VIB Ghent University 9052 Gent Belgium

Recently, we reported that the novel mitochondrial RNA editing factor SLO2 is essential for mitochondrialelectron transport, and vital for plant growth through regulation of carbon and energy metabolism. Here, we show thatmutation in SL02 causes hypersensitivity to ABA and insensitivity to ethylene, suggesting a link with stress ***, slo2 mutants are hypersensitive to salt and osmotic stress during the germination stage, while adult plantsshow increased drought and salt tolerance. Moreover, slo2 mutants are more susceptible to Botrytis cinerea *** increased expression of nuclear-encoded stress-responsive genes, as well as mitochondrial-encoded NAD genes ofcomplex I and genes of the alternative respiratory pathway, was observed in slo2 mutants, further enhanced by ABAtreatment. In addition, H202 accumulation and altered amino acid levels were recorded in slo2 mutants. We conclude thatSLO2 is required for plant sensitivity to ABA, ethylene, biotic, and abiotic stress. Although two stress-related RNA editingfactors were reported very recently, this study demonstrates a unique role of SLO2, and further supports a link betweenmitochondrial RNA editing events and stress response.

关键词： ABA Arabidopsis thaliana ethylene plant stress mitochondria RNA editing PPR protein SLO2 stress

Surface‑applied or incorporated biochar and compost combination improves soil fertility,Chinese cabbage and papaya biomass

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Biochar 2021年第2期3卷 213-227页

作者： Justine Cox Nguyen V.Hue Amjad Ahmad Kent D.Kobayashi Tropical Plant and Soil Sciences University of Hawaii3190 Maile WayHonoluluHI 96822USA present address:NSW Department Primary Industries 1243 Bruxner HighwayWollongbarNSW 2477Australia

Many Hawaiian agricultural soils are acidic with low-nutrient retention;therefore,organic soil amendments are often used to improve soil properties and increase *** can be incorporated for annual crops,but perennial orchards need surface application to avoid damaging surface *** trials compared responses to incorporated(IBC)or surface-applied(SBC)combination of hardwood biochar and chicken manure compost(4%v/v of each amendment)added to an Andisol and *** pH was increased by 0.4-1.1 units in IBC and by 0.2-0.5 for SBC in the 0-10 cm soil *** SBC and IBC increased soil total N,extractable P,Ca and Mg in the 0-10 cm soil *** pH,total C and extractable Ca were also higher in the 10-20 cm soil layer for IBC soil,indicating movement and/or leaching of *** cabbage biomass was 18-70%higher in the IBC and 14-47%higher in the SBC than that in the unamended soil,while papaya biomass was 23%and 19%higher in SBC and IBC,*** was a greater response in the more acidic Andisol soil,with larger improvements in soil pH,plant nutrient uptake and root biomass than the *** application was as effective in increasing plant growth as the incorporated amendment,providing evidence for farm scale *** and compost are recommended for use in tropical soils,and surface application may be beneficial to annual and perennial crops.

关键词： Surface-applied Andisol Oxisol Carica papaya Brassica rapa chinensis Biochar

How Sugars Might Coordinate Chloroplast and Nuclear Gene Expression during Acclimation to High Light Intensities

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Molecular Plant 2014年第7期7卷 1121-1137页

作者： Rainer E. Haiusler Luisa Heinrichs Jessica Schmitz Ulf-Ingo Flugge Department of Botany II Cologne Biocenter University of Cologne ZuIpicherstr. 47b 50674 Cologne Germany present address: Plant Molecular Physiology and Biotechnology Heinrich-Heine-University Universitatsstrasse 1 40225 D~sseldorfGermany

The concept of retrograde control of nuclear gene expression assumes the generation of signals inside the chloroplasts, which are either released from or sensed inside of the organelle. In both cases, downstream signaling path- ways lead eventually to a differential regulation of nuclear gene expression and the production of proteins required in the chloroplast. This concept appears reasonable as the majority of the over 3000 predicted plastidial proteins are encoded by nuclear genes. Hence, the nucleus needs information on the status of the chloroplasts, such as during acclimation responses, which trigger massive changes in the protein composition of the thylakoid membrane and in the stroma. Here, we propose an additional control mechanism of nuclear- and plastome-encoded photosynthesis genes, taking advantage of pathways involved in sugar- or hormonal signaling. Sugars are major end products of photosynthesis and their con- tents respond very sensitively to changes in light intensities. Based on recent findings, we ask the question as to whether the carbohydrate status outside the chloroplast can be directly sensed within the chloroplast stroma. Sugars might syn- chronize the responsiveness of both genomes and thereby help to coordinate the expression of piastome- and nuclear- encoded photosynthesis genes in concert with other, more specific retrograde signals.

关键词： acclimation--physiological assimilate allocation/partitioning carbohydrate metabolism molecular physiology membrane proteins Arabidopsis.

TRANSESTERIFICATION IN POLYPHENYLSILSISQUIOXANE(PPSQ)/POLY ETHYLENE TEREPHTHALATE (PET) BLENDS

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Chinese Journal of Polymer Science 1995年第4期13卷 366-374页

作者：李桂芝施良和叶美玲赵春田徐懋 Polymer Physics Laboratory Institute of Chemistry Academia Sinica Beijing 100080 Present Address: Department of Chemistry Shandong University Jinan 250100 Polymer Physics Laboratory Institute of Chemistry Academia Sinica Beijing 100080

The chemical structure of copolymer formed in the transesterification of PPSQ/PET blendsduring melt-processing is deduced from the;H-NMR spectra. The transesterification extent ofthis blend is interpreted by the changes of crystalline melting peak in DSC thermograms of the in-soluble products containing unreacted PET and some block PPSQ segments. Effects of composi-tion of blend ladderlike regularity of PPSQ on the reaction extent have also been *** of some block PPSQ segments in PET has no influence on the crystalline morphology ofPET.

关键词： Transesterification Polyphenylsilsisquioxane/PET blend