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Luminescent properties of praseodymium doped Y_2O_3 and LaAlO_3 nanocrystallites and polymer composites

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Journal of Rare Earths 2011年第12期29卷 1123-1129页

作者： m.Dudek A.Jusza K.anders L.Lipińska m.Baran R.Piramidowicz Faculty of Physics Warsaw University of Technology Institute of microelectronics and Optoelectronics Warsaw University of Technology Institute of Electronic materials Technology

Luminescent properties of Y2O3 and LaAlO3 nanopowders doped with Pr^3＋ ions and PmmA-based composite materials doped with these powders were reported. The set of active nanopowders differing in praseodymium ions concentration was prepared using sol-gel method and carefully characterized with respect to emission properties in the visible spectral range. In particular, the excitation and emission spectra were measured together with fluorescence decay profiles and the differences between optical properties of these materials were discussed and compared with data available for bulk materials. Finally, the PmmA-based composite materials doped with Pr^3＋：Y2O3 and Pr^3＋：LaAlO3 nanopowders were manufactured and characterized. The obtained results showed that polymer composites doped with active nanopowders in general tended to keep the luminescent properties of the original nanopowders.

关键词： nanocrystals praseodymium Y2O3 LaAlO3 visible emission PmmA nanocomposites rare earths

mAGNETIC FIELD EFFECT ON PHOTOPOLYmERIZATION OF STYRENE mICROEmULSION

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Chinese Journal of Polymer Science 1993年第1期11卷 1-7页

作者：陈用烈 anders Hult Bengt Ranby Institute of Polymer Science Zhongshan University Guangzhou Department of Polymer Technology The Royal Institute of Technology Stockholm Sweden

External magnetic field increases the photo-induced polymerization rate of styrene *** type of photoinitiator plays an important role. The photoinitiators, used are dimethoxyphenyl acetophenone(DmPA), 1-hydroxycyclohexyl phenylketone (Irgacure 184) and dimethylhydroxyacetophenone (Darocur 1173). No magnetic effect was observed by using dibenzylketone (DBK) as photoinitiator. The molecular weight of the polymer is slightly affected by magnetic field. The influence of temperature has also been investigated.

关键词： DmPA mAGNETIC FIELD EFFECT ON PHOTOPOLYmERIZATION OF STYRENE mICROEmULSION

An Analytical method for Calculating P-SV Acoustical Field Excited by a Piezoelectric Strip with Finite Width and Thickness

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Chinese Physics Letters 2005年第11期22卷 2869-2872页

作者：张碧星汪承灏 anders Bostroem Institute of Acoustics Chinese Academy of Sciences Beijing 100080 Department of Applied mechanics Chalmers University of Technology SE-412 96 Goeteborg Sweden

A piezoelectric strip with finite width and thickness is placed on top of an isotropic elastic half-space. Acoustical field can be excited when a voltage is across the piezoelectric strip. An analytical method is presented to calculate the acoustical field by the dynamics characteristics of the piezoelectric strip. Considering the piezoelectric strip as an anisotropic material of the 6 mm-type crystal system, we study the two-dimensional P-SV acoustical fields inside the piezoelectric strip and the isotropic half-space. The displacement and stress distributions are analysed thoroughly. The effects of the width and thickness of the piezoelectric strip and other parameters on the acoustical field are also analysed.

关键词： An Analytical method for Calculating P-SV Acoustical Field Excited by a Piezoelectric Strip with Finite

Androgen deprivation therapy and side effects:are GnRH antagonists safer?

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Asian Journal of Andrology 2021年第1期23卷 3-10页

作者： Stephen J Freedland Per-anders Abrahamsson Division of Urology Department of SurgeryCedars-Sinai Medical CenterLos AngelesCA 90048USA Section of Urology Durham VA Medical CenterDurhamNC 27705USA Department of Urology SkSne University HospitalLund UniversityMalmo 20502Sweden.

Androgen deprivation therapy(ADT)with gonadotropin-releasing hormone(GnRH)agonists and antagonists is the mainstay of advanced prostate cancer *** drug classes decrease levels of luteinizing hormone and follicle-stimulating hormones(FSH),thereby lowering testosterone to castrate *** is associated with adverse events(AEs),including cardiovascular(CV)disorders,bone fractures,metabolic dysfunction,and impaired cognitive *** literature review discusses these AEs,with a focus on CV and bone-related events.A hypothesis-generating meta-analysis of six clinical trials showed a potentially increased risk for CV disorders with GnRH agonists versus the GnRH antagonist *** no study has directly compared GnRH agonists versus antagonists with a primary CV outcome,one hypothesis for this observation is that GnRH agonists lead to initial surges in FSH that may negatively impact CV health,whereas antagonists do *** agonists are associated with metabolic and cognitive AEs and while data are lacking for GnRH antagonists,no differences in risk are *** common AEs with ADT include injection site reactions,which are much more common with degarelix than with GnRH agonists,which may reflect differing administration and injection *** studies are needed to further evaluate and compare the safety profiles of GnRH agonists and antagonists,especially in patients with pre-existing CV disease and other *** should carefully evaluate benefits and risks when prescribing ADT and ensure that side effects are well managed.

关键词： androgen antagonists metabolic syndrome prostate cancer safety

Why responses to dramatic climate change are important？

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Current Zoology 2011年第3期57卷 350-350页

作者： anders.pape moller No list

Climate change is proceeding at an unprecedented pace with global temperatures and sea-levels setting new records almost every year （IPCC, 2007）. While these changes are worrisome due to effects on all biological systems and hence also on humans, even more problematic changes may be in the waiting, because not only is the climate changing, but it is also becoming more extreme. Extreme temperatures, rainfall, droughts, storms and fires are already becoming more common with severe consequences for humans, their crops and domestic animals and all wild organisms. For example, the severe heat wave in 2003 caused an excess mortality of 2,600 humans in France alone （INSERm, 2003）, and primary production was suppressed across Europe （Ciais et al. 2004）.

关键词：气候变化反应 IPCC 全球气温生物系统野生生物初级生产海平面

The effects of temperature and resource availability on denitrification and relative N_(2)O production in boreal lake sediments

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Journal of Environmental Sciences 2016年第9期28卷 82-90页

作者： maria myrstener anders Jonsson Ann-Kristin Bergstrom Department of Ecology and Environmental Science Umea University90187 UmeaSweden

Anthropogenic environmental stressors（like atmospheric deposition,land use change,and climate warming） are predicted to increase inorganic nitrogen and organic carbon loading to northern boreal lakes,with potential consequences for denitrification in ***,our ability to predict effects of these changes is currently limited as northern boreal lakes have been largely neglected in denitrification *** aim of this study was therefore to assess how maximum potential denitrification and N_2O production rates,and the relationship between the two（relative N_2O production）,is controlled by availability of nitrate（NO_3^-）,carbon（C）,phosphorus（P）,and *** were performed using the acetylene inhibition technique on sediments from a small,nutrient poor boreal lake in northern Sweden in *** potential denitrification and N_2O production rates at 4°C were reached already at NO_3^-additions of 106–120 μg NO_3^-–N/L,and remained unchanged with higher NO_3 *** incubation temperatures increased maximum potential denitrification and N_2O production rates,and Q10 was somewhat higher for N_2O production（1.77） than for denitrification（1.69）.The relative N_2O production ranged between 13% and 64%,and was not related to NO_3^-concentration,but the ratio increased when incubations were amended with C and P（from a median of 16% to 27%）.Combined,our results suggests that unproductive northern boreal lakes currently have low potential for denitrification but are susceptible to small changes in NO_3 loading especially if these are accompanied by enhanced C and P availability,likely promoting higher N_2O production relative to N_2.

关键词： Acetylene NO3 Carbon DOC Nitrous oxide ratio Sediment

Exponential Set-Point Stabilization of Underactuated Vehicles moving in Three-Dimensional Space

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IEEE/CAA Journal of Automatica Sinica 2022年第2期9卷 270-282页

作者： Xiaodong He Zhiyong Sun Zhiyong Geng anders Robertsson State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceCollege of EngineeringPeking UniversityBeijing 100871China IEEE Department of Electrical Engineering Eindhoven University of Technology(TU/e)5600 MB Eindhoventhe Netherlands Department of Automatic Control LTHLund University22100 LundSweden

This paper investigates the stabilization of underactuated vehicles moving in a three-dimensional vector *** vehicle’s model is established on the matrix Lie group SE(3),which describes the configuration of rigid bodies globally and *** focus on the kinematic model of the underactuated vehicle,which features an underactuation form that has no sway and heave *** compensate for the lack of these two velocities,we construct additional rotation matrices to generate a motion of rotation coupled with ***,the state feedback is designed with the help of the logarithmic map,and we prove that the proposed control law can exponentially stabilize the underactuated vehicle to the identity group element with an almost global domain of ***,the presented control strategy is extended to set-point stabilization in the sense that the underactuated vehicle can be stabilized to an arbitrary desired configuration specified in ***,simulation examples are provided to verify the effectiveness of the stabilization controller.

关键词： Exponential stabilization logarithmic feedback matrix Lie group underactuated vehicle

Quantum Spin Liquid Phase in the Shastry–Sutherland model Detected by an Improved Level Spectroscopic method

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Chinese Physics Letters 2022年第7期39卷 105-116页

作者： Ling Wang Yalei Zhang anders W.Sandvik Department of Physics Zhejiang UniversityHangzhou 310000China Beijing Computational Science Research Center Beijing 100193China Department of Physics Boston UniversityBostonMassachusetts 02215USA Beijing National Laboratory for Condensed matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China

We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps between states with different quantum numbers. The crossing points of some of the relative(composite) gaps have much weaker finite-size drifts than the normally used gaps defined only with respect to the ground state, thus allowing precise determination of quantum critical points even with small clusters. Our results support the picture of a spin liquid phase intervening between the well-known plaquette-singlet and antiferromagnetic ground states, with phase boundaries in almost perfect agreement with a recent density matrix renormalization group study, where much larger cylindrical lattices were used [J. Yang et al., Phys. Rev. B 105, L060409(2022)]. The method of using composite low-energy gaps to reduce scaling corrections has potentially broad applications in numerical studies of quantum critical phenomena.

关键词： red SSm Sutherland model Detected by an Improved Level Spectroscopic method Quantum Spin Liquid Phase in the Shastry model

CO_2 Capture technologies: Current status and new directions using supported ionic liquid phase (SILP) absorbers

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Science China Chemistry 2012年第8期55卷 1648-1656页

作者： KOLDING Helene FEHRmANN Rasmus RIISAGER anders Centre for Catalysis and Sustainable Chemistry Department of Chemistry Building 207 Technical University of Denmark2800 Kgs. Lyngby Denmark

Current state-of-the-art techniques for COz capture are presented and discussed, Post-combustion capture of CO2 by absorption is the technology most easily retrofitted to existing installations, but at present this is not economically viable to install and run. Using ionic liquids instead of aqueous amine solutions overcomes the major thermodynamic issues. By applying SILP tech- nology further advances, in terms of ease of handling and sorption dynamics, are obtained. Initial experimental studies showed that ionic liquids such as tetrahexylammonium prolinate, [N6666][Pro], provide a good candidate for CO2 absorption using SILP technology. Thus a solid SILP absorber comprised of 40 wt% [N6666][Pro] loaded on precalcined silica quantitatively takes up about 1.2 mole CO2 per mole of ionic liquid in consecutive absorption-desorption cycles in a flow-experiment per- formed with 0.09 bar of CO2 （9% CO2 in He）.

关键词： CO2 capture absorption ionic liquids SILP absorber