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Chinese Chemical Letters 2018年第6期29卷 757-764页

作者： stephen Rhatigan Michael Nolan Tyndall National Institute University College Cork

Surface modification with metal oxide nanoclusters has emerged as a candidate for the enhancement of the photocatalytic activity of titanium dioxide. An increase in visible light absorption and the suppression of charge carrier recombination are necessary to improve the efficiency. We have studied Mg4O4 and Sn4O4 nanoclusters modifying the（101） surface of anatase TiO2 using density functional theory corrected for on-site Coulomb interactions（DFT ＋ U）. Such studies typically focus on the pristine surface, free of the point defects and surface hydroxyls present in real surfaces. We have also examined the impact of partial hydroxylation of the anatase surface on a variety of outcomes such as nanocluster adsorption, light absorption, charge separation and reducibility. Our results indicate that the modifiers adsorb strongly at the surface, irrespective of the presence of hydroxyl groups, and that modification extends light absorption into the visible range while enhancing UV activity. Our model for the excited state of the heterostructures demonstrates that photoexcited electrons and holes are separated onto the TiO2 surface and metal oxide nanocluster respectively. Comparisons with bare TiO2 and other TiO2-based photocatalyst materials are presented throughout.

关键词： Photocatalyst Titania Visible-light absorption Surface modification Charge separation Surface hydroxylation Oxygen vacancy formation

Defects in Statically Unstable Solids: The Case for Cubic Perovskite α-CsPbI3

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Chinese Physics Letters 2022年第4期39卷 28-35页

作者： Xiaowei Wu Chen Ming Jing Shi Han Wang Damien west Shengbai Zhang Yi-Yang Sun State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Department of Physics Jiangxi Normal UniversityNanchang 330022China Chemical Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720USA Department of Physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNew York 12180USA

High-temperature phases of solids are often dynamically stable ***-principles study of point defects in such solids at 0 K is prohibited by their static instability,which results in random structures of the defect-containing supercell so that the total energy of the supercell is randomly affected by structural distortions far away from the *** cubic perovskiteα-Cs Pb I_(3) as an example,we first present the problem incurred by the static instability and then propose an approach based on molecular dynamics to carry out ensemble average for tackling the *** affordable simulation time,we obtain converged defect ionization energies,which are unattainable by a standard approach and allow us to evaluate its defect tolerance *** work paves the way for studying defects in statically unstable solids.

关键词： property solids defect

A Review of Structural Health Monitoring Techniques as Applied to Composite Structures

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Structural Durability & Health Monitoring 2017年第2期11卷 91-147页

作者： Amafabia,Daerefa-a Mitsheal Montalvao,Diogo David-west,Opukuro Haritos,George Division of Automotive Mechanical and Mechatronics EngineeringSchool of Engineering and TechnologyUniversity of HertfordshireHatfield AL109ABUnited Kingdom Department of Design and Engineering Faculty of Science and TechnologyBournemouth UniversityPoole BH125BBDorsetUnited Kingdom

Structural Health Monitoring(SHM)is the process of collecting,interpreting and analysing data from structures in order to determine its health status and the remaining life *** materials have been extensively use in recent years in several industries with the aim at reducing the total weight of structures while improving their mechanical ***,composite materials are prone to develop damage when subjected to low to medium impacts(i.e.1-10 m/s and 11-30 m/s respectively).Hence,the need to use SHM techniques to detect damage at the incipient initiation in composite materials is of high *** the availability of several SHM methods for the damage identification in composite structures,no single technique has proven suitable for all *** must be noted that the amount of techniques available nowadays is too extensive to be comprehensively reviewed in a single ***,the focus will be on techniques that can serve as a starting point for studies focusing on damage detection,localisation,assessment and prognosis on certain kinds of ***,the line of thought behind the search and the structure of this review is a result of objectives beyond the scope of the paper ***,it was considered that,once the above was understood,an updated synopsis such as this could also be useful for other researchers in the same field.

关键词： SHM composite structures damage identification failure mechanisms low impact techniques

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Tribute to ***-Zhao Feng

Journal of Palaeogeography 2023年第1期12卷 4-7页

作者： stephen Kershaw Journal of Palaeogeography

I first met Prof Feng in September 2013 at the 1st International Palaeogeography Conference(IPC)in Beijing in the China University of Petroleum,Changping *** was so motivated in the development of the Journal of Palaeogeography and the International Society of Palaeogeography,and was very impressive of his support for younger scientists as the future generation of palaeogeographers.

关键词： younger geography Petroleum

Endocrine disruptors and falling sperm counts： lessons learned or not!

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Asian Journal of Andrology 2013年第2期15卷 191-194,I0005页

作者： stephen Safe Department of Veterinary Physiology and Pharmacology Texas A&M University College Station TX 77843-4466 USA Institute of Biosciences and Technology Texas A&M Health Science Center Houston TX 77030 USA

In summary, it has become evident that multiple factors can affect sperm counts and quality. Most reports indicate that there has not been a worldwide decrease in sperm counts over the past 20 or 50 years, and the validity of the endocrine disruptor hypothesis or testicular dysgenesis syndrome with respect to sperm counts is highly questionable.

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CHEMICALLY DEPOSITED SILVER FILM USED AS A SERS-ACTIVE OVER-COATING LAYER FOR POLYMER FILM

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Chinese Journal of Polymer Science 2001年第3期19卷 265-268页

作者： stephen Z.D. Cheng Department of Polymer Science The University of Akron Akron OH 44325 USA

When colloidal silver particles were chemically deposited onto polymer film as an over-coating layer, surface-enhanced Raman scattering (SERS) spectra could be collected for the surface analysis. SERS measurements of ... 详细信息

关键词： surface enhanced Raman scattering chemically deposited silver polymer film

INDOMETHACIN INHIBITS hCG AND GnRH AGONIST-INDUCED SECRETION OF PLASMINOGEN ACTIVATOR BY GRANULOSA AND THECA INTERSTITIAL CELLS OF HYPOPHYSECTOMIZED RATS

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Science China Chemistry 1988年第7期31卷 807-817页

作者：刘以训,CAJANDER stephen Laboratory of Reproductive Biology Institute of Zoology Academia Sinica Beijing Department of Reproductive Medicine M-025 University of California San Diego La Jolla CA 92093 USA

Considerable data have shown that plasminogen activator (PA) may play an important role in the mechanism of ovulation. A recent report argued that PA is not a primary proteoIytic enzyme for follicular rupture because a dose of indomethacin that blocked ovulation did not inhibit ovarian PA content. To further clarify the specific role of PA in the ovulation, we have carefully examined the effect of indomethacin on the secretion of PA in granulosa and theca-interstitial (TI) cells following hCG or GnRH agonist administration in PMSG-primed hypophysectomized immature rats. We have also studies in vitro action of this compound on PA secretion in granulosa cells. The results indicate that indomethacin can only suppress hCG- and GnRH agonist-induced PA secretion, but not suppress the ovarian content of these enzymes.

关键词： indomethacin hCG GnRH agonist plasminogen activator ovulation.

Improving the wind and temperature measurements of an airborne meteorological measuring system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第10期13卷 723-746页

作者： stephen FOSTER P.W.CHAN Aventech Research Inc. BarrieON L4N 2E3Canada Hong Kong Observatory KowloonHong KongChina

The Aircraft Integrated Meteorological Measuring System 20 Hz(AIMMS-20) has been used by the Hong Kong Observatory(HKO),China in data collection for tropical cyclone situations over the South China Sea and windshear and turbulence measurement at the Hong Kong International Airport(HKIA).This paper discusses possible methods for further enhancing the quality of the wind and temperature measurements from the *** wind measurement,the enhancement methods include:error modelling of the accelerometer(e.g.,bias offset and cross-axis rate sensitivity),global positioning system(GPS) phase lag consideration,better representation of the inertial measurement unit(IMU) velocity based on the GPS velocities and considering their location differences,consideration of the slower update of GPS velocity,and wing *** temperature measurement,the methods include the consideration of the temperature sensor response and the sensor housing *** results of typical flights using AIMMS-20 show that the accuracy of the wind and temperature data could be improved by 20%-30%.Though the discussion in the present paper is related mainly to a specific meteorological measuring system on a particular aircraft,the techniques so employed should be a useful reference for similar systems installed on other aircraft.

关键词： Airborne meteorological measurements Kalman filter Comparison with radiosonde measurement

Distributed Majorization-Minimization for Laplacian Regularized Problems

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 45-52页

作者： Jonathan Tuck David Hallac stephen Boyd IEEE the Department of Electrical Engineering Stanford University

We consider the problem of minimizing a block separable convex function(possibly nondifferentiable, and including constraints) plus Laplacian regularization, a problem that arises in applications including model fitting, regularizing stratified models, and multi-period portfolio optimization. We develop a distributed majorization-minimization method for this general problem, and derive a complete, self-contained, general,and simple proof of convergence. Our method is able to scale to very large problems, and we illustrate our approach on two applications, demonstrating its scalability and accuracy.

关键词： Convex optimization distributed optimization graphical networks Laplacian regularization

Power plant selection in a carbon constrained world the TERA(technoeconomic environmental risk analysis)

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航空动力学报 2009年第4期24卷 896-902页

作者： stephen Ogaji Pericles Pilidis Vishal Sethi Department of Power and Propulsion School of Engineering Cranfield University

There is an increasing concern that current trends of consumption of natural resources cannot *** is imperative that major targeted investments are made into economical and reliable environment friendly propulsion and power *** novel and promising concepts are being *** selection of the best candidates to pursue for investment becomes a very difficult choice.A detailed TERA(techno-economic environmental risk analysis) framework is described here to quantify risks and to compare and rank competing schemes on a formal and consistent *** technique is based on detailed and rigorous thermodynamic representations of power plants.A layer of environment,economic,weather and other models to describe the appropriate local conditions is superimposed to *** outcome is a techno-economic environmental risk analysis framework with appropriate detail of each power plant as applied to the appropriate *** results for each concept can then be compared and contrasted to make appropriate selections.

关键词： TERA(techno-economic environmental risk analysis) techno-economic risk analysis gas turbine multi-disciplinary optimisation(MDO)