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Fabrication,microstructures,and optical properties of Yb:Lu_(2)O_(3) laser ceramics from co-precipitated nano-powders

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Journal of Advanced Ceramics 2020年第6期9卷 674-682页

作者： Ziyu LIU guido toci Angela PIRRI Barbara PATRIZI Yagang FENG Jiabei WEI Feng WU Zhaoxiang YANG Matteo VANNINI Jiang LI Key Laboratory of Transparent Opto-functional Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Istituto Nazionale di Ottica Consiglio Nazionale delle RicercheCNR-INOSesto Fiorentino(Fi)50019Italy Istituto di Fisica Applicata“N.Carrara” Consiglio Nazionale delle RicercheCNR-IFACSesto Fiorentino(Fi)50019Italy School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013China

The Yb:Lu_(2)O_(3)precursor made up of spherical particles was synthesized through the co-precipitation method in the water/ethanol *** 5 at% Yb:Lu_(2)O_(3)powder is in the cubic phase after calcination at 1100℃ for 4 *** powder also consists of spherical nanoparticles with the average particle and grain sizes of 96 and 49 nm,*** average grain size of the pre-sintered ceramic sample is 526 nm and that of the sample by hot isostatic pressing grows to 612 *** 1.0 mm-thick sample has an in-line transmittance of 81.6%(theoretical value of 82.2%)at 1100 *** largest absorption cross-section at 976 nm is 0.96×1^(0-20)cm^(2) with the emission cross-section at 1033 nm of 0.92×10^(-20)cm^(2) and the gain cross sections are calculated with the smallest population inversion parameter β of *** highest slope efficiency of 68.7% with the optical efficiency of 65.1% is obtained at 1033.3 nm in quasi-continuous wave(QCW)*** the case of continuous wave(CW)pumping,the highest slope efficiency is 61.0% with the optical efficiency of 54.1%.The obtained laser performance indicates that Yb:Lu_(2)O_(3)ceramics have excellent resistance to thermal load stresses,which shows great potential in high-power solid-state laser applications.

关键词： Yb:Lu_(2)O_(3)transparent ceramics co-precipitated nano-powder spectroscopic properties laser performance hot isostatic pressing

共沉淀纳米粉体制备Yb:CaF2激光陶瓷及其性能研究（英文）

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无机材料学报 2019年第12期34卷 1341-1348页

作者：韦家蓓 toci guido PIRRI Angela PATRIZI Barbara 冯亚刚 VANNINI Matteo 李江中国科学院上海硅酸盐研究所透明光功能无机材料重点实验室上海200050 中国科学院大学材料科学与光电工程中心北京100049 意大利国家研究委员会国立光学研究所佛罗伦萨50019 意大利国家研究委员会“Carrara”应用物理研究所佛罗伦萨50019 意大利国家研究委员会国立光学研究所比萨56124

利用共沉淀法合成的粉体,通过真空烧结结合热压烧结后处理制备了掺镱的氟化钙透明陶瓷(Yb:CaF2)。在600℃预烧1 h,700℃热压烧结2 h制备的5at%Yb:CaF2透明陶瓷在1200 nm处的直线透射率达到92.0%。对陶瓷的显微结构、光谱特性和激光性能... 详细信息

利用共沉淀法合成的粉体,通过真空烧结结合热压烧结后处理制备了掺镱的氟化钙透明陶瓷(Yb:CaF2)。在600℃预烧1 h,700℃热压烧结2 h制备的5at%Yb:CaF2透明陶瓷在1200 nm处的直线透射率达到92.0%。对陶瓷的显微结构、光谱特性和激光性能进行了测试和讨论。研究结果表明,陶瓷样品的显微结构均匀,平均晶粒尺寸为360 nm。此外,计算得到Yb:CaF2陶瓷在977nm处的吸收截面和1030nm处的发射截面分别为0.39×10–20和0.26×10–20cm2。最后,对Yb:CaF2陶瓷激光性能进行了表征,得到最大输出功率为0.9 W,最大斜率效率为23.6%。

关键词： Yb:CaF2 共沉淀法两步烧结激光陶瓷光学性能

固体激光用Nd:Lu_(2)O_(3)透明陶瓷的制备和光学性能研究

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无机材料学报 2021年第2期36卷 210-216页

作者：刘子玉 toci guido PIRRI Angela PATRIZI Barbara 冯亚刚陈肖朴胡殿君田丰吴乐翔 VANNINI Matteo 李江中国科学院上海硅酸盐研究所透明光功能无机材料重点实验室上海201899 中国科学院大学材料与光电研究中心北京100049 意大利国家研究委员会国立光学研究所佛罗伦萨50019 意大利国家研究委员会“Carrara”应用物理研究所佛罗伦萨50019

Nd:Lu_(2)O_(3)材料由于具有高热导率、低声子能量和优异的光学特性而成为非常有前景的高功率固体激光器用的增益介质。但Lu_(2)O_(3)单晶的熔点超过2400℃,难以生长,而Lu_(2)O_(3)陶瓷既能在低温下制备,又具有与晶体相当的光学性质和... 详细信息

Nd:Lu_(2)O_(3)材料由于具有高热导率、低声子能量和优异的光学特性而成为非常有前景的高功率固体激光器用的增益介质。但Lu_(2)O_(3)单晶的熔点超过2400℃,难以生长,而Lu_(2)O_(3)陶瓷既能在低温下制备,又具有与晶体相当的光学性质和激光性能从而备受关注。本研究制备了高透明的Nd:Lu_(2)O_(3)陶瓷并对其光学性质和激光性能进行探究。以共沉淀法制备的纳米粉体为原料,采用真空烧结结合热等静压(HIP)两步烧结法制备了1.0at%Nd:Lu_(2)O_(3)透明陶瓷。对制备的粉体、素坯和陶瓷的微结构进行了表征:HIP后处理的陶瓷平均晶粒尺寸是724.2nm。厚度为1.0mm的1.0at%Nd:Lu_(2)O_(3)透明陶瓷在1100 nm处的直线透过率是82.4%,样品在806 nm处的吸收截面为1.50×10^(-20)cm^(2),而根据荧光光谱计算得到的发射截面为6.5×10^(–20)cm^(2)。分别在878.8和895.6 nm波长激发下,1.0at%Nd:Lu_(2)O_(3)透明陶瓷(4)^F3/2→(4)^I11/2跃迁的平均荧光寿命均为169ms。当输出耦合镜的透过率TOC=2.0%时,退火后的1.0at%Nd:Lu_(2)O_(3)透明陶瓷获得了最大输出功率为0.47 W的准连续(QCW)激光输出,斜率效率为8.7%。本研究成功制备了显微结构均匀、高透明度的1.0at%Nd:Lu_(2)O_(3)陶瓷,并展示了其在固体激光增益介质领域的广阔应用潜力。

关键词： Nd:Lu2O3透明陶瓷共沉淀法两步烧结光学性能激光性能

Intraoperative cholangio-ultrasonography(IOCUS)during hepatectomy with resection of the biliary confluence:An effective alternative to intraoperative cholangiography

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 417-420页

作者： Daniele Del Fabbro Fabio Procopio Jacopo Galvanin guido Costa Simone Famularo Angela Palmisano Matteo Donadon guido Torzilli Division of Hepatobiliary Surgery Department of SurgeryIRCCS Humanitas Research HospitalVia A.Manzoni 56Rozzano 20089MilanItaly Department of Biomedical Sciences Humanitas UniversityVia Rita Levi Montalcini 4Pieve Emanuele 20072MilanItaly

Intraoperative ultrasonography(IOUS)in hepatobiliary surgery is well known as an essential tool for radical and safe hepatectomies,allowing to perform parenchymal sparing surgery and,as consequence,to expand the surgical indications for patients otherwise considered ***,since many years,despite its effectiveness in the study of vascular anatomy of the liver,the gold standard for the assessment of biliary anatomy during surgery is intraoperative cholangiography(IOC),which is used for the validation of preoperative imaging as well as for guiding reconstruction in case of bile duct injury or resection.

关键词： anatomy biliary ultrasonography

Getting the Most Out of Every Training Day: The Influence of Instructors on Self-Regulated Learning During Firefighter Leadership Courses

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International Journal of Disaster Risk Science 2024年第3期15卷 332-345页

作者： Stefan R?seler Micha Hilbert guido Hertel Meinald T.Thielsch Department of Psychology University of Münster

Leadership courses in the fire services are highly challenging, and they can seriously exhaust trainees and hamper their selfregulated learning efforts(for example, setting goals, focusing attention, seeking feedback). We theorize that experiences of failure or overload can curtail trainees' available energy resources on subsequent training days, which, in turn, should affect trainees' learning efforts. Given instructors' central role in leadership courses, we hypothesize that supportive and humble instructor behaviors decrease experiences of failure and overload and, thus, increase self-regulated learning. Moreover, we argue that supportive instructor behavior may amplify the positive effects of high energy resources, while humble behavior may alleviate the negative impact of low resource levels. We tested preregistered hypotheses with 118 firefighters participating in two-week leadership courses at a German fire academy. The participants completed short web-based questionnaires before and after classes each day. Multilevel analyses confirmed that perceived daily supportive and humble instructor behavior predicted trainees' reports of daily self-regulated learning activity. Notably, this effect was independent from positive effects of trainees' reported energy resources in the morning. Supportive and humble behavior did not moderate the eff ect of energy resources. Our findings suggest that instructors play a crucial role in facilitating effective learning under challenging training conditions. Furthermore, we offer implications for leaders in fire services, who often conduct trainings with their subordinates.

关键词： Diary study Fire services Instructor behavior Leadership training Resource investment

Lipid-derived radical-trapping antioxidants suppress ferroptosis

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Life Metabolism 2024年第2期3卷 6-8页

作者： Ruoxi Zhang guido Kroemer Daolin Tang Department of Surgery UT Southwestern Medical CenterDallasTX 75390United States Centre de Recherche des Cordeliers INSERM U1138Equipe labellisée-Ligue contre le cancerUniversitéParis CitéSorbonne UniversitéInstitut Universitaire de FranceParis 75006France Metabolomics and Cell Biology Platforms Gustave Roussy Cancer CampusVillejuif 94800France Institut du Cancer Paris CARPEM Department of BiologyHôpital Européen Georges PompidouAssistance Publique-Hôpitaux de ParisParis 75015France

Ferroptosis,characterized by lipid peroxidation-mediated cell demise,is governed by a nuanced interplay of lipid species influencing its *** recent publications in Nature discovered 7-dehydrocholesterol,a cholesterol precursor,as a radical-trapping antioxidant that can suppress ferroptosis,thereby presenting a novel metabolic target to improve ferroptosis-related cancer therapy.

关键词： Lipid peroxidation cholesterol

Predicting cardiovascular events in out-of-hospital patients presenting with atypical chest pain and complete left bundle branch block: role of CTA and echocardiographic Global Longitudinal Strain

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Journal of Geriatric Cardiology 2024年第7期21卷 760-767页

作者： guido Pastorini Fabio Anastasio Anna Botto Valentina Tardivo Mauro Feola Cardiology Division Regina Montis Regalis HospitalASLCN1Mondovi’Italy Intensive Care Regina Montis Re-galis HospitalASLCN1 Mondovi’Italy School of Geriatry University of MedicineTurinItaly

Background Out-of-hospital patients presenting with atypical chest pain and complete left bundle branch block(LBBB)have to be stratified for the presence of coronary artery disease and the risk of developing heart failure(HF).We investigated the pro-gnostic role of coronary CT-angiography(CTA)and echocardiographic global longitudinal strain(GLS)in those patients in a mid-term *** Out-of-hospital patients with LBBB underwent echocardiography and a 64-slice CT angiography were evaluated *** of HF or a cardiovascular death were the events *** Seventy-eight patients(32 female;mean age:66.0±10.4 years were *** a follow-up of 33 months(IQR:17-77),one patient(1.5%)experienced a cardiovascular death,14 patients(17.9%)required urgent outpatient visits due to acute de-compensated HF(12 hospitalizations).Echocardiography showed a slightly reduced left ventricular ejection fraction(LVEF)(50.0%±9.8%)and GLS within the normal range(-16.2%±4.1%).CTA analysis showed coronary stenosis>50%in 28 patients(35.9%).A high Agatston score(>100)was observed in 29.5%.Notably,25 patients(32.1%)were diagnosed with left main coron-ary artery disease and 15 patients(16.7%)underwent revascularization during the follow *** associations were ob-served between events and LVEF(P=0.001),diastolic dysfunction grade≥2(P=0.02),GLS(P<0.001),multiple coronary stenos-is(P=0.04)and Agatston score(P=0.05).Multivariate analysis confirmed the relationships with LVEF(R2=0.89,P<0.001),dia-stolic dysfunction(R2=3.30,P=0.04),GLS(R2=1.43,P<0.001),and Agatston score(R2=1.01,P=0.05).Conclusions In patients with complete LBBB,CTA and GLS identified those at a high risk of development HF.

关键词： patients echocardiographic branch

The formation and growth mechanisms of young back-arc spreading ridges from high-resolution bathymetry:The Marsili Seamount(Tyrrhenian Sea,Italy)

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Geoscience Frontiers 2024年第1期15卷 325-338页

作者： Eugenio Nicotra Salvatore Passaro guido Ventura Dipartimento di Biologia Ecologia e Scienze della Terra Universitàdella Calabria87036 Arcavacata di RendeCosenzaItaly Istituto di Scienze Marine CNR 80133 NapoliItaly Istituto Nazionale di Geofisica e Vulcanologia 00143 RomaItaly Istituto per lo Studio degli impatti Antropici e Sostenibilitáin ambiente marino CNR 91026 Capo GranitolaTrapaniItaly

The formation and growth mechanisms of Mid-Ocean Ridges(MOR)are relatively well known,whereas those of back-arc spreading ridges are comparatively less known because geophysical,geochemical,and morphological data are scarce and of low *** we present a high-resolution bathymetry of the Marsili Seamount(MS;1 Ma-3 ka),which represents the inflated spreading ridge of the 2 Ma old Marsili back-arc basin associated to the subduction of the Ionian Sea below the Calabrian Arc and Tyrrhenian *** is 70 km long,30 km wide,and its height reaches about 3000 m from surrounding *** new digital bathymetric model has a 5 m grid cell size resolution and covers the MS bathymetry from-1670 mbsl to the top at-491 *** conduct morphometric and morphological analyses of the bathymetry and recognize landforms due to volcanic,tectonic,hydrothermal and gravity *** consists of volcanoes related to fissural and central-type activity,this latter located at the northern and southern tips of the main dike *** swarms represent the surface expression of different ridge segments whose strikes are controlled by the larger scale back-arc spreading processes and by the local occurrence of an active hydrothermal *** latter develops in a flat area between two partly overlapping ridge segments where historical volcanism and extensional processes *** ridges represent the embryonic stage of the formation of transform-like *** volcanoes,the northern of which is characterized by a caldera,form at the tips of MS because the decrease in width of the major volcanic fissures promotes vent localization associated with the formation of sill-like reservoirs from which central-type vents may *** processes affecting the MS flanks are due to shallow seafloor *** collapses affecting the northernmost central-type polygenic volcano must be included in the evaluation of the hazard related to potential *** dipping faul

关键词： Back-arc spreading ridge Morphology Tectonics Volcanism Marsili seamount

Profiles of the Headspace Volatile Organic and Essential Oil Compounds from the Tunisian Cardaria draba (L.) Desv. and Its Leaf and Stem Epidermal Micromorphology

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Phyton-International Journal of Experimental Botany 2024年第4期93卷 725-744页

作者： Wissal Saadellaoui Samiha Kahlaoui Kheiria Hcini Abir Haddada Noomene Sleimi Roberta Ascrizzi guido Flamini Fethia Harzallah-Skhiri Sondes Stambouli-Essassi Laboratory of Biodiversity Biotechnology and Climate Change(LR11-ES09)Faculty of Sciences of TunisUniversity of Tunis El ManarTunis1060Tunisia Laboratory RME-Resources Materials and EcosystemsFaculty of Sciences of BizerteUniversity of CarthageJarzounaBizerte7021Tunisia Dipartimento di Farmacia Universitàdi PisaVia Bonanno 33Pisa56126Italy Laboratory of Bioresources:Integrative Biology and Valorization(LR14-ES06) High Institute of Biotechnology of MonastirUniversity of MonastirMonastir5000Tunisia

In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total of 37 volatileorganic compounds (96.7%–98.9%) were identified;4 esters, 4 alcohols, 7 hydrocarbons, 12 aldehydes, 5 ketones,1 lactone, 1 organosulfur compound, 2 organonitrogen compounds, and 1 acid. The hydrocarbons form the maingroup, representing 49.5%–84.6% of the total detected volatiles. The main constituent was 2,2,4,6,6-pentamethylheptane(44.5%–76.2%) reaching the highest relative percentages. Forty-two compounds were determined in thetwo fractions of EOs, representing 98.8% and 97.2% of the total oil composition, respectively. The principal componentswere hexadecanoic acid (34.6%), 6-methyl-5-hepten-2-one (18.3%), decanal (15.0%), 6,10,14-trimethyl-2-pentadecanone (13.2%), and n-pentacosane (13%). Micromorphological details of the leaf and stem epidermisusing light microscopy revealed polygonal cells with sinuous walls in the adaxial and abaxial leaf surfaces andnearly rectangular and long ones with linear and thick walls for the stem epidermis. The stomata complexes wereanisocytic in the leaf epidermis and mainly anisocytic and rarely paracytic in the stem epidermis. Non-glandulartrichomes were unbranched and long with an acute apex or short with a convex apex. The glandular ones wereidentified for the first time in this species. They were short-stalked with a large secretory head. The highest stomatalindex (17.02%) was recorded in the abaxial leaf surface. The identification of headspace volatiles and essentialoil compounds can be used to characterize this species, and the various epidermis micromorphologicalfeatures are very useful for biosystematics taxonomic studies within Brassicaceae.

关键词： Cardaria draba aroma profile essential oils epidermis trichomes