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effect of excitation wavelength(blue vs near UV)and dopant concentrations on afterglow and fast decay of persistent phosphor SrAl_(2)O_(4):eu^(2+),Dy^(3+)

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Journal of Rare earths 2022年第7期40卷 1022-1028页

作者： Bernhard Walfort Nando Gartmann Jafar Afshani Arnulf Rosspeintner Hans Hagemann LumiNova AG SwitzerlandSpeicherstrasse 60aCH-9053TeufenSwitzerland Dépt.de Chimie Physique Universitéde Genève30Quai E.AnsermetCH 1211Geneva 4Switzerland

The persistent phosphor SrAl_(2)O_(4):eu^(2+),Dy^(3+)is the subject of numerous *** often neglected aspect is that in this phosphor,as well as in Sr_(4)Al_(14)O_(25):eu^(2+),Dy^(3+),there are two different Sr^(2)+sites which can be occupied by the dopant eu^(2+)ions,We first introduce a general scheme of possible energy transfers in these persistent phosphor materials including explicitly both europium ions,This scheme is used as a generic starting point to study experimentally specific *** illustrate this application with the study of the effect of excitation wavelength(444 and 382 nm)on the afterglow of differently doped SrAl_(2)O_(4):eu^(2+),Dy^(3+)samples,as well as on the emission decay *** the same excitation intensity under 444 nm excitation,the resulting afterglow intensity is stronger than under near UV *** 382 nm,eu^(2+)ions on both Sr^(2)+s ites in SrAl_(2)O_(4)are excited,but at room temperature the blue emission is quenched,leading to a loss of *** observed effects can further be associated with the ratio of eu^(2+)ions and trap states which are modulated by the concentrations of eu^(2+)and Dy^(3+)in SrAl_(2)O_(4),as well as by temperature,Increasing the nominal Dy^(3+)content from 0.1 mol%to 0.5 mol%with respect to Sr results in the doubling of the integrated afterglow intensity and confirms thus that Dy^(3+)ions are indeed involved in the trapping process,The concentration of trap states is much lower than the concentration of eu^(2+)ions,as even with low excitation densities,a plateau of integrated afterglow intensity(corresponding to the total number of accessible traps)is *** postulate that an important fraction of excited eu^(2+)ions can potentially transfer their energy to trap *** that all traps are filled or in a dynamical filling-depletion process under illumination(with thermal and/or optical depletion processes),for the remaining eu^(2+)a"normal"steady-state emission is observed

关键词： Persistent phosphor Strontium aluminate europium Forster energy transfer Rare earths

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Giant multiphononic effects in a perovskite oxide

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npj Computational Materials 2023年第1期9卷 1352-1358页

作者： Claudio Cazorla Massimiliano Stengel JorgeÍñiguez Riccardo Rurali Departament de Física Universitat Politècnica de CatalunyaCampus Nord B4-B5Barcelona 08034Spain Institut de Ciència de Materials de Barcelona ICMAB–CSICCampus UAB08193 BellaterraSpain ICReA-InstitucióCatalana de Recerca i estudis Avançats 08010 BarcelonaSpain Materials Research and Technology Department Luxembourg Institute of Science and Technology(LIST)Avenue des Hauts-Fourneaux 5L-4362 Esch/AlzetteLuxembourg Department of Physics and Materials Science University of Luxembourg41 Rue du BrillL-4422 BelvauxLuxembourg

Perovskite oxides offer tremendous potential for applications in information storage and energy conversion,owing to a subtle interplay between their spin,charge,orbital and lattice degrees of ***,we further expand the possible range of perovskite oxides operation towards the fields of thermal management and thermal computing by exploiting an exceptional synergy between different ferroic *** propose dynamical control of the heat flow in a distinctive family of perovskite oxides obtained via the application of small electric(~10 kV/cm)and/or magnetic(~1 T)*** on first-principles simulations,we predict a relative heat conductivity variation of~100%in SrMnO_(3) thin films near room temperature resulting from a phase transition that involves huge changes in both the magnetization and electric *** disclosed giant multiphononic effects are fundamentally caused by anharmonic spin-phonon couplings that strongly influence the mean lifetime of phonons.

关键词： perovskite oxides exceptional

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An experimental study on the effects of relative rotation direction on the wake interferences among tandem wind turbines

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Science China(Physics,Mechanics & Astronomy) 2014年第5期57卷 935-949页

作者： YUAN Wei TIAN Wei OZBAY Ahmet HU Hui Department of Aerospace engineering Iowa State University227 Howe Hall - Room 1200AmesIowa 50011USA School of energy and Power engineering Beihang University School of Aeronautics and Astronautics Shanghai Jiao Tong University

An experimental study was conducted to investigate the effects of relative rotation direction on the wake interferences among two tandemwind turbines *** the oncoming flow conditions were kept in constant during the experiments,turbine power outputs,wind loads acting on the turbines,and wake characteristics behind the turbines were compared quantitatively with turbine models in either co-rotating or counter-rotating *** measurement results reveal that the turbines in counter-rotating would harvest more wind energy from the same oncoming wind,compared with the co-rotating *** the recovery of the streamwise velocity deficits in the wake flows was found to be almost identical with the turbines operated in either co-rotating or counter-rotating,the significant azimuthal velocity generated in the wake flow behind the upstream turbine is believed to be the reason why the counter-rotating turbines would have a better power production *** the azimuthal flow velocity in the wake flow was found to decrease monotonically with the increasing downstream distance,the benefits of the counter-rotating configuration were found to decrease gradually as the spacing between the tandem turbines *** the counter-rotating downstream turbine was found to produce up to 20%more power compared with that of co-rotating configuration with the turbine spacing being about 0.7D,the advantage was found to become almost negligible when the turbine spacing becomes greater than *** suggests that the counter-rotating configuration design would be more beneficial to turbines in onshore wind farms due to the smaller turbine spacing(i.e.,~3 rotor diameters for onshore wind farms vs.~7 rotor diameters for offshore wind farms in the prevailing wind direction),especially for those turbines sited over complex terrains with the turbine spacing only about 1–2 rotor diameters.

关键词：风力涡轮机尾流干扰旋转方向实验串联方位角速度海上风电场反向旋转

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Correction to: Hybrid image of three contents

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Visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 81-83页

作者： Peeraya Sripian Yasushi Yamaguchi SIT Research Laboratory Shibaura Institute of TechnologyRoom#04R313-7-5 ToyosuKoto-kuTokyo 135-8548Japan The University of Tokyo Bldg.#15Room#505A3-8-1KomabaMeguro-kuTokyo 153-8902Japan

In the original publication of this article[1],the Figs.3 and 4 are not clear *** are adjusted the size and showed as below.

关键词： enough adjusted image

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Houttuynia cordata Thunb rescues retinal ganglion cells through inhibiting microglia activation in a rat model of retinal ischemia-reperfusion

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International Journal of Ophthalmology(english edition) 2020年第12期13卷 1880-1886页

作者： Le-Meng Ren Ying-Hui Zhang The First Clinical Medical College Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Medical Record room the Second Hospital of Shandong UniversityShandong UniversityJinan 250033Shandong ProvinceChina

AIM:To determine whether Houttuynia cordata Thunb(HCT)can increase the survival of the retinal ganglion cells(RGCs)and inhibit microglia activation following retinal ischemia-reperfusion(RIR)***:Rat model of RIR was induced by transient elevation of the intraocular pressure(IOP).HCT was orally administered for 2 d before the performance of retinal RIR model and once a day for the next 14 *** 14 d of RIR injury,the rats were sacrificed for further *** RGCs were stained with haematoxylin and eosin(H&e).Apoptosis of RGCs was detected by TUNeL *** function was examined by flash-electroretinography(F-eRG).Retinal microglia were labeled using Iba-1,one specific marker for *** m RNA expression levels of inducible nitric oxide synthase(i NOS),tumor necrosis factor alpha(TNF-α),and interleukin 1 beta(IL-1β)were assessed by quantitative real time reverse transcription polymerase chain reaction(q RT-PCR).ReSULTS:Systemic HCT treatment significantly reduced RGCs death by H&e staining and exhibited an anti-apoptotic effect as assessed by TUNeL staining at day 14 after RIR *** greatly improved the retinal function as examined by *** number of activated microglia significantly increased after RIR injury,which was significantly attenuated by HCT ***,RIR injury induced a strong upregulation of pro-inflammatory genes TNF-α,i NOS and IL-1βm RNAs at day 14 post injury,which was suppressed by ***:Neuroprotective effects of HCT encourage the survival of RGCs through inhibiting microglia activation due to RIR *** these results support the use of HCT as promising therapy for the ischemic events of the retina diseases.

关键词： Houttuynia cordata Thunb retinal ganglion cell microglia activation retinal ischemia-reperfusion

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Mini-percutaneous Nephrolithotomy Under Total Ultrasonography in Patients Aged Less Than 3 Years： A Single-center Initial experience from China

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Chinese Medical Journal 2015年第12期128卷 1596-1600页

作者： Bo Xiao Xin Zhang Wei-Guo Hu Song Chen Yu-Hong Li Yu-Zhe Tang Yu-Bao Liu Jian-Xing Li Department of Urology Beijing Tsinghua Changung Hospital Medical Center Tsinghua University Beijing 102218 China Department of Operating room Beijing Tsinghua Changung Hospital Medical Center Tsinghua University Beijing 102218 China

Background：Urolithiasis in pediatric population is a serious problem with the incidence increased these *** the management of larger stones （diameters 〉2 cm）,percutaneous nephrolithotomy （PCNL） is considered to be the gold *** study aimed to investigate the efficacy and safety of mini-PCNL under total ultrasonography in patients aged 〈3 ***：We reviewed 68 patients （80 renal units） aged 〈3 years between August 2006 and December 2014 in Peking University People＆#39;s Hospital and Beijing Tsinghua Changung Hospital,including 36 renal units with a single stone,6 with staghom stones,14 with upper ureteral stones,and 24 with multiple *** mean age of the patients was 24.2 months （range 6-36 months）,and the mean maximum stone diameter was 19.2 mm （range 10-35 mm）.The puncture site selection and tract dilation were guided by Doppler ultrasonography *** procedures were performed using 12-16 Fr *** were fragrnented using pneumatic lithotripsy and a holmium laser with an 8/9.8 Fr rigid ***：Fifty-six patients with unilateral stones underwent a single session procedure,and 12 patients with bilateral stones underwent two *** mean time to establish access was 2.8 min （range 1.8-5.0 min）,the mean operative time was 36.5 min （range 20-88 min）,the mean decrease in hemoglobin concentration was 8.9 g/L （2-15 g/L）,and the stone-free rate （SFR） at hospital discharge was 94.0%.The mean postoperative hospital stay was 7.1 days （range 3-13 days）.Postprocedure complications included fever （〉38.5℃） in five patients and reactive pleural effusion in one *** loss requiring transfusion,sepsis,adjacent organ injury,and kidney loss were not ***：This study indicated that ultrasound-guided mini-PCNL is feasible and safe in patients aged 〈3 years,without major complications or radiation exposure.

关键词： Calculi Infant Kidney Percutaneous Nephrolithotorny Ultrasonography

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Large edge magnetism in oxidized few-layer black phosphorus nanomeshes

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Nano Research 2017年第2期10卷 718-728页

作者： Yudai Nakanishi Ayumi Ishi Chika Ohata David Soriano Ryo Iwaki Kyoko Nomura~ Miki Hasegawa Taketomo Nakamura Shingo Katsumoto Stephan Roche Junji Haruyama Faculty of Science and engineering Aoyama Gakuin University 5- I0-1 Fuchinobe Sagamihara Kanagawa 252-5258 Japan Chemistry and Biological Science Aoyama Gakuin University 5-10-1 Fuchinobe Sagamihara Kanagawa 252-5258 Japan Catalan Institute of Nanoscience and Nanotechnology (ICN2) CSIC and The Barcelona Institute of Science and Technology Campus UAB Bellaterra 08193 Barcelona Spain Institucio Catalana de Recercai estudis Avancats (ICReA) 08010 Barcelona Spain Institute for solid state physics The University of Tokyo 5- I-5 Kashiwanoha Kashiwa Chiba 277-8581 Japan

The formation and control of a room-temperature magnetic order in two- dimensional （2D） materials is a challenging quest for the advent of innovative magnetic- and spintronic-based technologies. To date, edge magnetism in 2D materials has been experimentally observed in hydrogen （H）-terminated graphene nanoribbons （GNRs） and graphene nanomeshes （GNMs）, but the measured magnetization remains far too small to allow envisioning practical applications. Herein, we report experimental evidences of large room-temperature edge ferromagnetism （FM） obtained from oxygen （O）-terminated zigzag pore edges of few-layer black phosphorus （P） nanomeshes （BPNMs）. The magnetization values per unit area are -100 times larger than those reported for H-terminated GNMs, while the magnetism is absent for H-terminated BPNMs. The magnetization measurements and the first-principles simulations suggest that the origin of such a magnetic order could stem from ferromagnetic spin coupling between edge P with O atoms, resulting in a strong spin localization at the edge valence band, and from uniform oxidation of full pore edges over a large area and interlayer spin interaction. Our findings pave the way for realizing high-efficiency 2D flexible magnetic and spintronic devices without the use of rare magnetic elements.

关键词： black phosphorus nanomesh edge magnetism spintronics zigzag edge oxygen termination rare-metal free

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Methodologies for preparation of prokaryotic extracts for cell-free expression systems

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Synthetic and Systems Biotechnology 2020年第4期5卷 252-267页

作者： Stephanie D.Cole Aleksandr e.Miklos Abel C.Chiao Zachary Z.Sun Matthew W.Lux US Army Combat Capabilities Development Command Chemical Biological Center 8567 Ricketts Point RoadAberdeen Proving GroundMD21010USA Division of Biology and Biological engineering California Institute of TechnologyPasadenaCAUSA Synvitrobio Inc. San FranciscoCAUSA 8567 Ricketts Point Road Bldg E3549 Room B140APGMD21010USA

Cell-free systems that mimic essential cell functions,such as gene expression,have dramatically expanded in recent years,both in terms of applications and widespread *** we provide a review of cell-extract methods,with a specific focus on prokaryotic ***,we describe the diversity of escherichia coli genetic strains available and their corresponding *** then trace the history of cell-extract methodology over the past 20 years,showing key improvements that lower the entry level for new ***,we survey the rise of new prokaryotic cell-free systems,with associated methods,and the opportunities ***,we use this historical perspective to comment on the role of methodology improvements and highlight where further improvements may be possible.

关键词： Cell-free systems Cell-free expression Cell-free extract Synthetic biology Methods

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Recurrent perimesencephalic nonaneurysmal subarachnoid hemorrhage within a short period of time: A case report

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World Journal of Clinical Cases 2021年第14期9卷 3356-3364页

作者： Juan Li Xiang Fang Fu-Chao Yu Bin Du Operating room Nurse Jinan Central Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina Operating room Nurse Jinan Central Hospital Affiliated to Shandong UniversityJinan 250000Shandong ProvinceChina Department of Neurosurgery Jinan Central Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina Department of Neurosurgery Jinan Central Hospital Affiliated to Shandong UniversityJinan 250000Shandong ProvinceChina

BACKGROUND Spontaneous subarachnoid hemorrhage(SAH)is primarily caused by a ruptured intracranial *** nonaneurysmal SAH(PNSAH)accounts for approximately 5%of all spontaneous *** displays favorable *** risk of hemorrhage recurrence is *** report a case of PNSAH recurrence,occurring within a short time after the initial episode in a patient not receiving antithrombotic or antiplatelet *** SUMMARY A 66-year-old male,without any history of recent trauma or antithrombotic/antiplatelet medication,suffered two similar episodes of sudden onset of severe headache,nausea,and vomiting.A plain head computed tomography(CT)scan showed subarachnoid blood confined to the anterior part of the *** count and coagulation function were *** was diagnosed by repeated head CT,magnetic resonance imaging,and cerebral angiography,none of which revealed the source of *** patient was discharged without focal neurological *** 6-mo follow-up,the patient had experienced no sudden onset of severe headache and presented favorable clinical *** have reported a few patients with recurrent PNSAH,originating frequently from venous hemorrhage and conventionally associated with venous *** recurs within a short time following the initial onset of symptoms,although the possibility of re-hemorrhage is extremely *** PNSAH recurrence should arouse vigilance;however,the definite source of idiopathic SAH in this case report deserves further attention.

关键词： Negative angiography Perimesencephalic nonaneurysmal subarachnoid hemorrhage Recurrence Computed tomography Prognosis Case report

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Microstructure,mechanical properties and fracture behaviors of large-scale sand-cast Mg-3Y-2Gd-1Nd-0.4Zr alloy

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Journal of Magnesium and Alloys 2023年第8期11卷 2763-2775页

作者： Lixiang Yang Yuanding Huang Zhengquan Hou Lv Xiao Yuling Xu Xiwang Dong Fei Li Gerrit Kurz Baode Sun Zhongquan Li Norbert Hort Shanghai Key Lab of Advanced High-temperature Materials and Precision Forming and State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China MagIC-Magnesium Innovation Centre and Institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck Straße 121502 GeesthachtGermany Shanghai Spaceflight Precision Machinery Research Institute Shanghai 201600China Institute of Material and Process Design Helmholtz-Zentrum HereonMax-Planck Straße 121502 GeesthachtGermany

In order to improve the ductility of commercial We43 alloy and reduce its cost,a Mg-3Y-2Gd-1Nd-0.4Zr alloy with a low amount of rare earths was developed and prepared by sand casting with a differential pressure casting *** microstructure,mechanical properties and fracture behaviors in the as-cast,solution-treated and as-aged states were *** is found that the aged alloy exhibited excellent comprehensive mechanical properties owing to the fine dense plate-shapedβ'precipitates formed on prismatic habits during aging at 200℃for 192 hrs after solution-treated at 500℃for 24 *** ultimate tensile strength,yield strength,and elongation at ambient temperature reach to 319±10 MPa,202±2 MPa and 8.7±0.3%as well as 230±4 MPa,155±1 MPa and 16.0±0.5%at 250℃.The fracture mode of as-aged alloy was transferred from cleavage at room temperature to quasi-cleavage and ductile fracture at the test temperature 300℃.The properties of large-scale components fabricated using the developed Mg-3Y-2Gd-1Nd-0.4Zr alloy are better than those of commercial We43 alloy,suggesting that the new developed alloy is a good candidate to fabricate the large complex thin-walled components.

关键词： Magnesium alloy We43 Large-scale sand-cast Ductility

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