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Temporal trends in concentrations of legacy and novel brominated flame retardants in house dust from Birmingham in the United Kingdom

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Emerging Contaminants 2020年第1期6卷 323-329页

作者： daniel simon drage Sonthinee Waiyarat Stuart Harrad Mohamed Abou-Elwafa Abdallah Suwanna Kitpati Boontanon School of Geography Earth&Environmental SciencesUniversity of BirminghamBirminghamB152TTUK department of Civil and Environmental Engineering Faculty of EngineeringMahidol UniversityNakhon PathomThailand

Concentrations of polybrominated diphenyl ethers(PBdEs),hexabromocyclododecane(HBCdd),tetrabromobisphenol-A(TBBPA)and two potential replacements decabromodiphenylethane(dBdPE)and 1,2-bis(2,4,6-tribromophenoxy)ethane(BTBPE)were measured in dust samples collected from 14 homes across Birmingham(UK).Concentrations were compared with those from the same city in previous studies to ascertain any temporal changes and to assess the effects of legislative *** average PHBCdds concentration(46,000 ng/g;median=280 ng/g)included the highest dust concentration recorded globally(570,000 ng/g).This is despite the listing of HBCdd under the Stockholm Convention in 2013,demonstrating that decreases in indoor contamination will likely be slow as existing sources are gradually *** contrast,concentrations of BdE-47(mean=5.7 ng/g;median=0.93 ng/g)and BdE-99(mean=11 ng/g;median=2.9 ng/g)were significantly lower than in all previous(pdies in the same city since 2006,suggesting restrictions on the Penta-BdE formulation have been *** average BdE-209 concentration(4800 ng/g;median=1600 ng/g)is lower than the peak average concentration,which was observed in 2007(280,000 ng/g),however this is not a significant decline,probably due to the later imposition of deca-BdE restrictions compared to those on *** in PBdE concentrations have coincided with a significant(pdBdPE concentrations(average=1500 ng/g;median=660 ng/g)since 2014,suggesting its use as a replacement flame retardant for *** no significant change was detected for BTBPE(average 11 ng/g;median=0.84 ng/g in this study);concentrations of TBBPA(average=34 ng/g;median=35 ng/g)were significantly lower(pdecreases observed in PBdE concentrations,demonstrates that legislation has been effective in reducing the commercial use of PBdEs,however this has coincided with increases of alternative flame retardants such as dBdPE.

关键词： Brominated Flame Retardants(BFRs) Polybrominated diphenyl ethers(PBdEs) Hexabromocyclododecane(HBCdd) decabromodiphenyl ethane(dBdPE) Stockholm convention Tetrabromobisphenol A(TBBPA) BTBPE

Integrating MEMS and ICs

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Microsystems & Nanoengineering 2015年第1期1卷 165-180页

作者： Andreas C.Fischer Fredrik Forsberg Martin Lapisa simon J.Bleiker Göran Stemme Niclas Roxhed Frank Niklaus department of Micro and Nanosystems School of Electrical EngineeringKTH Royal Institute of TechnologySE-10044 StockholmSweden

The majority of microelectromechanical system(MEMS)devices must be combined with integrated circuits(ICs)for operation in larger electronic *** MEMS transducers sense or control physical,optical or chemical quantities,ICs typically provide functionalities related to the signals of these transducers,such as analog-to-digital conversion,amplification,filtering and information processing as well as communication between the MEMS transducer and the outside ***,the vast majority of commercial MEMS products,such as accelerometers,gyroscopes and micro-mirror arrays,are integrated and packaged together with *** are a variety of possible methods of integrating and packaging MEMS and IC components,and the technology of choice strongly depends on the device,the field of application and the commercial *** this review paper,traditional as well as innovative and emerging approaches to MEMS and IC integration are *** include approaches based on the hybrid integration of multiple chips(multi-chip solutions)as well as system-on-chip solutions based on wafer-level monolithic integration and heterogeneous integration *** are important technological building blocks for the‘More-Than-Moore’paradigm described in the International Technology Roadmap for *** this paper,the various approaches are categorized in a coherent manner,their merits are discussed,and suitable application areas and implementations are critically *** implications of the different MEMS and IC integration approaches for packaging,testing and final system costs are reviewed.

关键词： cofabrication platforms integrated circuits(ICs) microelectromechanical system(MEMS) More-Than-Moore multichip modules(MCMs) system-in-package(SiP) system-on-chip(SoC) three-dimensional(3d)heterogeneous integration

Estimating Ocean Chlorophyll Using the Penalized Three dimensional (3d) Blending Technique

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Open Journal of Marine Science 2018年第3期8卷 386-394页

作者： Mathias A. Onabid simon Wood department of Mathematics-Computer Science Faculty of Sciences Dschang University of Dschang West Region Cameroon department of Mathematical Sciences University of Bath Bath UK

The Thin Plate Regression Spline (TPRS) was introduced as a means of smoothing off the differences between the satellite and in-situ observations during the two dimensional (2d) blending process in an attempt to calibrate ocean chlorophyll. The result was a remarkable improvement on the predictive capabilities of the penalized model making use of the satellite observation. In addition, the blending process has been extended to three dimensions (3d) since it is believed that most physical systems exist in the three dimensions (3d). In this article, an attempt to obtain more reliable and accurate predictions of ocean chlorophyll by extending the penalization process to three dimensional (3d) blending is presented. Penalty matrices were computed using the integrated least squares (ILS) and integrated squared derivative (ISd). Results obtained using the integrated least squares were not encouraging, but those obtained using the integrated squared derivative showed a reasonable improvement in predicting ocean chlorophyll especially where the validation datum was surrounded by available data from the satellite data set, however, the process appeared computationally expensive and the results matched the other methods on a general scale. In both case, the procedure for implementing the penalization process in three dimensional blending when penalty matrices were calculated using the two techniques has been well established and can be used in any similar three dimensional problem when it becomes necessary.

关键词： Integrated Least Squares Integrated Squared derivative Basis Function Penalty Matrix Penalized Model In-Situ Satellite

Emission spectroscopy of NaYF_(4):Eu nanorods optically trapped by Fresnel lens fibers

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Photonics Research 2022年第2期10卷 332-339页

作者： Aashutosh Kumar Asa Asadollahbaik Jeongmo Kim Khalid Lahlil simon Thiele Alois M.Herkommer Síle Nic Chormaic Jongwook Kim Thierry Gacoin Harald Giessen Jochen Flck Universite Grenoble Alpes CNRSInstitut Neel38000 GrenobleFrance 4th Physics Institute and Research Center SCoPE University of Stuttgart70569 StuttgartGermany Universite Paris Saclay CNRSLaboratoire de Physique de la Matiere CondenseeEcole Polytechnique91128 PalaiseauFrance Institute of Applied Optics and Research Center SCoPE University of Stuttgart70569 StuttgartGermany Okinawa Institute of Science and Technology Graduate University Okinawa 904-0495Japan

NaYF_(4):Eu nanorods with high aspect ratios are elaborated and optically trapped using dual fiber optical tweezers in a counterpropagating geometry. High trapping efficiency is observed using converging beams, emitted from diffractive Fresnel lenses directly 3d printed onto cleaved fiber facets. Stable nanorod trapping and alignment are reported for a fiber-to-fiber distance of 200 μm and light powers down to 10 m W. Trapping of nanorod clusters containing one to three nanorods and the coupling of nanorod motion in both axial and transverse directions are considered and discussed. The europium emission is studied by polarization-resolved spectroscopy with particular emphasis on the magnetic and electric dipole transitions. The respective σ and π orientations of the different emission lines are determined. The angles with respect to the nanorod axes of the corresponding magnetic and electric dipoles are calculated. Mono-exponential emission decay with decay time of 4–5 ms is reported. It is shown that the nanorod orientation can be determined by purely spectroscopic means.

关键词： nanorods Fresnel trapping

Large second-order nonlinearity induced in thermally poled Pyrex borosilicate glass

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Large second-order nonlinearity induced in thermally poled P...

Preclinical models in ophthalmic oncology-a narrative review

2007亚洲光电子会议非线形光学及应用分会场

作者： simon Fleming Optical Fibre Technology Centre University of Sydney 206 National Innovation Centre Australian Technology Park Eveleigh NSW 1430 Australia

Stable second-order nonlinearity (SON) was created in Pyrex borosilicate glass by the temperature/electric field thermal poling method. The distribution and amplitude of the induced nonlinearity were characterized with second harmonic microscopy. It was found that the SON was located in a narrow layer around 1.9 μm under the anode surface. An effective d33 as high as 0.24 pm/V was obtained;a value comparable to that obtained in fused silica samples. The migration of different mobile alkali ions during the poling process was characterized with energy dispersive x-ray spectrometry in conjunction with scanning electron microscopy (SEM). It was found that Na was depleted from a region about 3.3 μm beneath the anode surface, while K was first depleted from the immediate region under the anode, and then accumulated in the Na-depleted region with its peak at .8 μm beneath the anode. SEM observation of the cross-section of the poled glass region, after it had been etched in diluted hydrofluoric acid for several minutes, revealed an etched trench, .8 μm under the anode edge and .3 μm in width;while in post-annealed samples, no such etched trench could be observed. A frozen-in space-charge field due to charge migration is believed to be responsible for the creation of the SON and the altered etching rate in the poled region.

关键词： Thermal poling optical glass second-harmonic generation

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Annals of Eye Science 2022年第2期7卷 59-73页

作者： daria Lehrmann Nasrin Refaian Michael simon Alexander C.Rokohl Ludwig M.Heindl department of Ophthalmology Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany Center for Integrated Oncology(CIO) Aachen-Bonn-Cologne-DüsseldorfCologneGermany

Objective:This review serves as a comprehensive description and summary of currently available preclinical models of three tumors in ophthalmic oncology:conjunctival melanoma(CM),uveal melanoma(UM),and ***:Malignant melanomas are the most common tumors of the eye in adults,most often localized in the uvea and *** the primary tumor can be successfully eliminated in many cases,nearly one in two UMs-and one in three CMs-are fatal to the patient due to *** therapies for metastatic uveal and CMs are unfortunately still not available,so there is an urgent need for new therapeutic strategies to improve prognosis quoad vitam and prolong the survival of melanoma *** widely known tumor of the eye is retinoblastoma,which is the most common pediatric ocular malignancy,occurring in approximately 1 in 15,000-18,000 live ***,it is considered well treatable,with a survival rate of approximately 90%at 3 years,although fatal if *** a long time,enucleation was also considered the treatment of choice,with bilateral cases having one eye irradiated and the eye with the more advanced tumor *** the 1990s,however,systemic chemotherapy has been predominantly used to preserve the quality of life and vision of young patients,although the cellular activity of the retinoblastoma often remains after treatment with chemotherapeutic *** of the disease is immensely depending on the stage and time of diagnosis and is varying between countries due to different developmental status of health care ***:We review recent advances in the available literature on established preclinical models in CM,UM,and *** addition,we discuss the advantages and limitations of these models and provide an overview of current alternatives to animal testing in preclinical ***:In the case of all three diseases,further research is needed for improved therapeutic ***

关键词： Conjunctival melanoma(CM) uveal melanoma(UM) retinoblastoma ocular tumor preclinical models

Assessment of postcombustion carbon capture technologies for power generation

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Frontiers of Chemical Science and Engineering 2010年第2期4卷 184-195页

作者： Mikel C.dUKE Bradley LAdEWIG simon SMART Victor RUdOLPH João C.diniz da COSTA Institute for Sustainability and Innovation Victoria UniversityWerribee CampusPO Box 14428MelbourneVictoria 8001Australia department of Chemical Engineering Monash UniversityClayton Vic 3182Australia School of Chemical Engineering The University of QueenslandBrisbane Qld 4072Australia

A significant proportion of power generation stems from coal-combustion processes and accordingly represents one of the largest point sources of CO_(2)emissions *** power plants are major assets with large infrastructure and engineering units and an operating life span of up to 50 ***,any process design modification to reduce greenhouse gas emissions may require significant *** of the best options to utilize existing infrastructure is to retrofit the power station fleet by adding a separation process to the flue gas,a practice known as postcombustion capture(PCC).This review examines the recent PCC development and provides a summary and assessment of the state of play in this area and its potential applicability to the power generation *** major players including the various institutes,government,and industry consortia are identified along with flue gas PCC demonstration scale *** the PCC technologies reviewed,amine-based absorption is preeminent,being both the most mature and able to be adapted immediately,to the appropriate scale,for power station flue gas with minimal technical ***,current commercial applications serve niches in the merchant CO_(2)market,while a substantial number of smaller scale test facilities are reported in the literature with actual CO_(2)capture motivated demonstrations now *** membrane/absorption systems,also known as membrane contactors,offer the potential for the lowest energy requirements,possibly 10%of current direct scrubbers but are at an early stage of *** methods being actively pursued as R&d projects include solid absorbents,solid adsorbents,gas membrane separators,and cryogenic *** variety and different maturities of these competing technologies make technical comparison largely subjective,but useful insights could be gained through the development and application of econometric techniques such as‘real options’within this ***

关键词： post-carbon capture amine absorption adsorption membranes technology assessment

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番茄采摘机器人机械臂避障路径规划

农业机械学报 2012年第12期43卷 171-175,157页

作者：尹建军武传宇 Yang simon X Gauri S Mittal 毛罕平江苏大学现代农业装备与技术教育部重点实验室镇江212013 浙江理工大学机械与自动控制学院杭州310018 圭尔夫大学工程系

以关节型机械臂避开垂直茎秆或撑杆采摘番茄为研究对象,提出了一种基于构形空间的关节型机械臂避障路径规划方法。利用空间映射原理,将关节型机械臂工作空间的三维避障问题转换为平面R-R机械臂避开障碍圆的问题,用临界碰撞关节角建立C-... 详细信息

以关节型机械臂避开垂直茎秆或撑杆采摘番茄为研究对象,提出了一种基于构形空间的关节型机械臂避障路径规划方法。利用空间映射原理,将关节型机械臂工作空间的三维避障问题转换为平面R-R机械臂避开障碍圆的问题,用临界碰撞关节角建立C-障碍空间的映射计算模型,将工作空间的位置避障转换为构形空间连杆关节角的计算。以能量最优函数优选避障规划的关节终点角度,利用A*算法计算平面R-R机械臂的避障关节角路径,获得一系列表示空间连杆位置的相交竖直面,并在竖直面内进行其余关节角的规划。避障采摘番茄的试验表明,机械臂带动夹持器能成功绕过直线状障碍物,引导夹持器到达果实目标位置,证明对平面R-R机械臂的空间映射建模是正确的,验证了提出的避障路径规划方法是可行的,可以应用于番茄的自动收获。

关键词：番茄采摘机器人关节型机械臂路径规划避障

Contactless Raman Spectroscopy-Based Monitoring of Physical States of Silyl-Modified Polymers during Cross-Linking

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Green and Sustainable Chemistry 2016年第4期6卷 151-166页

作者： Boris Colin Olivier Lavastre Stéphane Fouquay Guillaume Michaud Frédéric simon Olivier Laferte Jean-Michel Brusson Laboratory of Functional Materials Institut Electronique Télecommunication Rennes Unité Mixte Recherche 6164 Centre National Recherche Scientifique University of RENNES 1 Rennes France Bostik Smart Technology Center Zac du bois de Plaisance 101 Venette France TOTAL S.A. Tour Michelet A 24 Cours Michelet La Defence France

Cross-linking of silyl-modified polymers occurs at the alkoxysilane groups attached to the ends of polymer chains by hydrolysis and polycondensation mechanisms in the presence of moisture. during these reactions, three different physical states can be identified (viscous, skin effect and cross-linked state). Knowledge of the evolution of these states at each reaction time is essential to determine the open time for the adhe-sive industry and is generally obtained by a manual method. Automation of this moni-toring could avoid operator error and could be used for very long cross linking reac-tions or to screen a large number of catalysts. Thus, a contactless micro process tech-nology was developed to correlate these physical states with an optical technology, Raman spectroscopy, by monitoring the decrease in intensity of the Si-OCH3 groups during chemical reactions. This online characterization method can also be used to compare the efficiencies of several catalysts for the cross-linking of silyl-modified polymers, using a minimum amount of chemical materials.

关键词： Silyl Modified Polymers Physical States Micro Contactless Monitoring Raman Spectroscopy Cross-Linking