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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

Relationship of MTHFR gene polymorphisms with renal and cardiac disease

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World Journal of Nephrology 2015年第1期4卷 127-137页

作者： Francesca M Trovato Daniela Catalano angela Ragusa G Fabio Martines Clara pirri Maria Antonietta Buccheri Concetta Di Nora Guglielmo M Trovato Department of Internal Medicine University of Catania95100 CataniaItaly AOU Prenatal Diagnosis and Medical Genetics University of Catania95100 CataniaItaly Internal and Emergency Medicine Department University of Catania95100 CataniaItaly

AIM: To investigate the effects of different methylenetetrahydrofolate reductase(MTHFR) 677C>T gene polymorphism and hyperhomocysteinemia for the development of renal failure and cardiovascular events, which are ***: We challenged the relationship, if any, of MTHFR 677C>T and MTHFR 1298A>C polymorphisms with renal and heart function. The present article is a reappraisal of these concepts, investigating within a larger population, and including a subgroup of dialysis patients, if the two most common MTHFR polymorphisms, C677 T and A1298 C, as homozygous, heterozygous or with a compound heterozygous state, show different association with chronic renal failure requiring hemodialysis. MTHFR polymorphism could be a favorable evolutionary factor, i.e., a protective factor for many ominous conditions, like cancer and renal failure. A similar finding was reported in fatty liver disease in which it is suggested that MTHFR polymorphisms could have maintained and maintain their persistence by an heterozygosis advantage mechanism. We studied a total of 630 Italian Caucasian subject aged 54.60 ± 16.35 years, addressing to the increased hazard of hemodialysis, if any, according to the studied MTHFR genetic polymorphisms. RESULTS: A favorable association with normal renal function of MTHFR polymorphisms, and notably of MTHFR C677 T is present independently of the negative effects of left ventricular hypertrophy, increased IntraRenal arterial Resistance and hyperparathyroidism. CONCLUSION: MTHFR gene polymorphisms could have a protective role on renal function as suggested by their lower frequency among our dialysis patients in end-stage renal failure; differently, the association with left ventricular hypertrophy and reduced left ventricular relaxation suggest some type of indirect, or concurrent mechanism.

关键词：还原酶肾衰竭治疗方法临床分析