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Synthesis of highly ordered Large Size Mesoporous Silica and Effect of Stabilization as Enzyme Supports in Organic Solvent

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chemical Research in chinese Universities 2002年第2期18卷 200-205页

作者： LI Bo Inagaki S Miyazaki c Takahashi h Toyota central R&D Labs. Inc.411YokomichiNagakute choAichi 4801192Japan

FSM 16, McM 41 and SBA 15 types of hexagonal mesoporous silica with a highly ordered 2 dimensional structure were synthesized by using different silicon sources and surfactants. In the 2 dimensional silicate framework, pore size can be uniformly controlled by the combined use of the surfactants having different alkyl chain lengths and the swelling agents(triisopropyl benzene). The pore diameter of FSM 16 and McM 41 can be expanded to be 10 nm, SBA 15 to be 15 nm. The crystal regularity was decreased with the increase of the pore diameter. In FSM 16 derived from kanemite(silicon source) and McM 41 from water glass, their anionic characteristics on the pore wall may be stronger than those of SBA 15 derived from oligomeric tetramethoxysilane(TMOS). We have successfully used FSM 16 and McM 41 to immobilize the enzyme having cationic residues below isoelectric point. The level of adsorption of enzymes in FSM 16 and McM 41 was relatively high, but was low in SBA 15 support. The mechanism of enzyme to be adsorbed in mesoporous silica was suggested to be the ionic interactions. In aqueous solutions, horseradish peroxidase(hTP) was immobilized in FSM 16 with 8.9 nm mesopores and the highest loading amount(183 mg/mg FSM) was obtained, but for the FSM 16 of pore diameter 30 nm only an amount of 28 mg/mg FSM was obtained. The catalytic activity in the organic solvent was high when hRP was immobilized in FSM 16 and McM 41, but it was low in case of SBA 15.

关键词： Mesoporous silica Surfactant Swelling agent Enzyme Activity

high resolution tracking of adult horseshoe crabs Limulus polyphemus in a New hampshire estuary using fixed array ultrasonic telemetry

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current Zoology 2010年第5期56卷 599-610页

作者： Winsor h.WATSON Ⅲ christopher c.chABOT Department of Biological Sciences University of New Hampshire Department of Biology Plymouth State University

While several studies have documented the large-scale, seasonal movements of horseshoe crabs, little is known about their fine-scale, daily movement patterns. In this study we used a fixed array ultrasonic telemetry system to track the movements of 12 male and 16 female horseshoe crabs in the Great Bay estuary, New hampshire. Data were obtained during the mating season, as well as during the remainder of the summer and fall, in the years 2005-2008. During the mating season animals were often, but not always, active during the high tides when they were approaching and leaving the spawning beaches. On average, both males and females approached mating beaches during 33% of the high tides they experienced and they most often made the tran- sition from being inactive to active during the last two hours of an incoming tide. From April-October horseshoe crabs were significantly more active during high tide periods vs low tide periods, with no clear preference for diurnal vs nocturnal activity. After the mating season ended horseshoe crabs continued to move into shallower water at high tide and then return to deeper water at low tide. Observations by ScUBA divers suggest that during these excursions into the mudflats horseshoe crabs were digging pits in the sediment while foraging for food. Thus, the tidal rhythm of activity that has been so well documented during the mating season probably persists into the fall, and primarily involves foraging activities

关键词： Telemetry Tracking Movements Mating Foraging Estuary

Layered Machinable and Electrically conductive Ti_2Alc and Ti_3Alc_2 ceramics:a Review

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Journal of Materials Science & Technology 2010年第5期26卷 385-416页

作者： X.h. Wang Y.c. Zhou Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang110016 China

Ti2Alc and Ti3Alc2 are the most light-weight and oxidation resistant layered ternary carbides belonging to the MAX *** review highlights recent achievements on the processing,microstructure,physical,mechanical and chemical properties of these two machinable and electrically conductive ***2Alc and Ti3Alc2 display superior properties such as fracture toughness,electrical and thermal conductivities,and oxidation resistance over their binary *** paper provides a comprehensive overview of the processing-microstructure-property correlations of these two *** fields of applications for Ti2Alc and Ti3Alc2 are *** addition,we point out methods for further improving their properties in some specific applications through appropriate structural design and modification.

关键词： MAX phases Ti2Alc Ti3Alc2 Machinable ceramics

The evolution of plant reproductive ecology in china

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Journal of Plant Ecology 2015年第2期8卷 101-108页

作者： Spencer c.h.Barrett Department of Ecology and Evolutionary Biology University of TorontoTorontoOntario M5S 3B2Canada

Scientific interest in plant reproduction has a long and venerable history going back to early European naturalists including carl Linnaeus,christian Konrad Sprengel,Joseph Kölreuter,Fritz and hermann Müller,George henslow and of course,charles *** can be considered the founder of modern plant reproductive *** three books(Darwin 1862,1876,1877)laid the conceptual foundation for the field,and many of the ideas they contain are still topics of active research(reviewed in Barrett 2010).The turn of the 20th century saw the rediscovery of Mendel’s Laws and breeding experiments on flowering plants played an important role in establishing many key elements of modern *** the 1940s,Fisher had developed the population genetic principles for theoretical analysis of the evolution of plant mating systems(Fisher 1941)。

关键词： reproductive plant evolution

Detection of Breaking Waves Using X-Band Pulse Radar in the Nearshore Region

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china Ocean Engineering 2013年第4期27卷 549-556页

作者： Y.c.Lin c.c.chang M.c.Lee h.c.chan J.M.Leu Department of hydraulic and Ocean Engineering National Cheng-Kung University Department of Soil and Water conservation National Chung Hsing University Department of hospitality Management Taiwan Shoufu University

An X-band pulsed Doppler microwave radar has been used to determine the characteristics of breaking waves. Field experiments were conducted at the Shuang-Si estuary in the north of Taiwan in the winter of 2005. Analyses on maxima radar cross section and Doppler frequency shift are done to characterize wave breaking zones. Based on observations of breaking waves, the wave breaking zones are shown to be located at water depths of 1.8 to 2.2 m in the experimental site. In general, the results indicate that a radar system has the potential to delineate the spatial variation of breaking waves clearly and that this is sufficient to achieve a measurement operation for near-shore air-sea interaction events.

关键词： radar Doppler effect wave breaking coastal zone

MODIFIcATION OF SODIUM SALT OF PARTIALLY cARBOXYMEThYLATED TAMARIND KERNEL POWDER ThROUGh GRAFTING WITh AcRYLONITRILE: SYNThESIS, chARAcTERIZATION AND SWELLING BEhAVIOR

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chinese Journal of Polymer Science 2013年第12期31卷 1670-1684页

作者： J.h.Trivedi J.R.Jivani K.h.Patel h.c.Trivedi P.G.Dept.of chemistry Sardar Patel UniversityVallabh Vidyanagar Amneal Phamaceuticals

A graft copolymer of polyacrylonitrile （PAN） with sodium salt of partially carboxymethylated tamarind kernel powder （Na-PcMTKP, DS ^-= 0.15） was synthesized by using ceric ammonium nitrate （cAN） as a redox initiator in an aqueous medium. The optimum reaction conditions for affording maximum percentage of grafting were established by successively varying reaction conditions such as concentrations of nitric acid, cAN, monomer （AN） as well as reaction time, temperature and amount of substrate. The influence of these reaction conditions on the grafting yields was discussed. The kinetic scheme of free radical graft copolymerization was proposed and the experimental results were found to agree very well with the proposed kinetic scheme. The graft copolymer （Na-PcMTKP-g-PAN, percentage of grafting G = 413.76% and percentage of grafting efficiency GE = 96.48%） sample synthesized under the established optimized reaction conditions was hydrolyzed by 0.7 mol-L l NaOh solution at 90-95 ℃ to yield the superabsorbent hydrogel, h-Na-PcMTKP-g-PAN. The swelling behavior of the hydrogel was studied by carrying out its absorbency measurements in low conductivity water, 0.15 mol·L^-1 salt （Nacl, cacl2 and Alcl3） solutions and simulated urine （SU） solution at different timings. FTIR, TGA and SEM techniques were used to characterize the products.

关键词： Sodium salt of partially carboxymethylated tamarind kernel powder Acrylonitrile Graft copolymerization Superabsorbent hydrogels Swelling behavior.

Electropulsing-Induced Microstructural changes and Their Effects on Electrical conductivity of Thin Films of an Al-doped ZnO

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1361-1367页

作者： Y.h.Zhu c.M.Luk Department of Industrial and Systems Engineering TheHong Kong Polytechnic UniversityHong KongChina Department of Applied Physics The Hong Kong PolytechnicUniversityHong KongChina

Electropulsing-induced phase decompositions and microstructural changes in AZO-5 thin films were studied by X-raydiffraction, scanning electron microscopy, atomic force microscopy, hall effect measurement and photoluminescence （PL）measurement techniques. It was found that the electropulsing induced phase decomposition started with spinodaldecomposition, which was accompanied by discontinuous precipitation in the AZO-5 thin films. Both circular phasedecompositions and the crystal orientation occurred. Inappropriate electropulsing might damage zones, which resulted intremendous decrease in electrical conductivity. circular changes in both the peak position and the width of the PLwavelength were observed in the EPT AZO-5 thin films. Formation of zones favored reducing the roughness of the thinfilm.

关键词： Electropulsing Phase transformation Electrical conductivity Photoluminescence Thin-films AZO

Optimal design of V-type ultrasonic motor

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Journal of central South University 2010年第6期17卷 1247-1250页

作者： JEONG S S PARK c h PARK T G School of Mechatronics Changwon National UniversityChangwon 641773Korea

V-type ultrasonic linear motor fabricated using a simple punching technique was proposed to utilize as an actuator of small precision *** stator of the motor is composed of a thin elastic body and four ceramics attached to the upper and bottom areas of the *** ceramics have each direction of *** two harmonic voltages with a 90° phase difference are applied to the ceramics,symmetric and anti-symmetric displacements will generate at the tip to produce an elliptical motion.A finite element analysis(ATILA) was conducted to simulate the motion pattern for the contact tip of the *** develop a model that generates the maximum displacement at contact tip,the FEM program was used for various *** addition,an optimal model was chosen by considering the magnitude and shape of the displacement according to changes in *** maximum elliptical displacement is shown by W2L11 model,which has a ratio of ceramic width to length of 1:***,the displacement of the contact tip is reduced by the bucking phenomenon if the ratio is larger than 1:6.

关键词： ultrasonic motor piezo-actuator finite element method optimal design elliptical motion

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chinese Annals of Mathematics,Series B 2002年第2期23卷 205-208页

作者： GU chAOhAO(c.h.GU) Institute of Mathematics FudanUniversity china.E-mail:guch

The purpose of the present paper is to call for attention to the following question: Which of the initial data (nonsmall) admit global smooth solutions to the cauchy problem for nonlinear wave equations. A few cases a... 详细信息

关键词： cauchy problem Initial data Global smooth solution