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Pulse generation of erbium-doped fiber laser based on liquid-exfoliated FePS3
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作者 阴晴 汪进 +8 位作者 史鑫尧 王涛 杨洁 赵新新 沈振江 吴坚 张凯 周朴 姜宗福 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第8期172-178,共7页
As a preferable material in the field of photo-detection and catalysis,the characteristics of FePS3 in broad wavelength range have been proven by many experimental studies.However,FePS3 has not been used as a saturabl... As a preferable material in the field of photo-detection and catalysis,the characteristics of FePS3 in broad wavelength range have been proven by many experimental studies.However,FePS3 has not been used as a saturable absorber(SA)in fiber lasers yet.We propose and demonstrate the generation of a single wavelength and dual-wavelength based on an Er-doped fiber laser(EDFL)at 1.5μm by using an innovative FePS3 saturable absorber for the first time.The result shows that a stable passively Q-switched pulse can be generated,which demonstrates that the new two-dimensional(2D)material FePS3 served as SA provides a valid method to realize passively Q-switched laser.In addition,we achieve the output of the dual-wavelength pulse by properly rotating the polarization controller.To the best of our knowledge,the dual-wavelength pulse EDFL could be applied in biomedicine,spectroscopy,and sensing research. 展开更多
关键词 FIBER LASER Q-SWITCHED FePS3
Loss induced negative refraction and super-prism effect at highly absorptive interface
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作者 吴坚 王涛 +4 位作者 侯天悦 阚雪芬 殷澄 周朴 曹庄琪 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第5期101-105,共5页
It is well-established that waves are inhomogeneous in a lossy isotropic medium,and the validation of the classical Snell’s law is still questionable for light refraction at the dissipative and dispersive interface.W... It is well-established that waves are inhomogeneous in a lossy isotropic medium,and the validation of the classical Snell’s law is still questionable for light refraction at the dissipative and dispersive interface.With high absorption,direct experimental investigation is rather difficult due to the extremely short penetration depth;i.e.,the skin depth.In this paper,a simple and unified description of this issue is proposed,which can be applied to both materials with anomalous dispersion and in the Drude region.The gradient ?kw is found to be incident angle qi-dependent,and the direction of the group velocity may deviate significantly from the phase velocity due to the loss induced permittivity structure.The physics behind the negative refraction effect is explained,and a novel loss induced super-prism effect is also predicted. 展开更多
关键词 Snell’s Law Drude model ANOMALOUS DISPERSION LOSSY ISOTROPIC media
Xp11.2易位/TFE3基因融合相关性肾细胞癌10例的临床病理特征 预览
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作者 简武 甘怀勇 +1 位作者 承泽农 蔡兆根 《临床与病理杂志》 2019年第3期503-508,共6页
目的:探讨Xp11.2易位/TFE3基因融合相关性肾细胞癌(Xp11.2 translocation/TFE3 gene fusion assoc iatedrenalcel lcarc inoma,X p11.2RCC)的临床病理特征。方法:收集和分析10例X p11.2RCC患者的临床病理资料,随访并复习相关文献。结果... 目的:探讨Xp11.2易位/TFE3基因融合相关性肾细胞癌(Xp11.2 translocation/TFE3 gene fusion assoc iatedrenalcel lcarc inoma,X p11.2RCC)的临床病理特征。方法:收集和分析10例X p11.2RCC患者的临床病理资料,随访并复习相关文献。结果:10例患者年龄18~76(中位33)岁。瘤体直径3.3~10.0 cm。光镜下肿瘤组织多呈乳头状或假乳头状排列,部分呈腺管状或巢状排列,肿瘤细胞胞质丰富透明或嗜酸性;细胞核深染至空泡状,部分可见清晰核仁;肿瘤间质多为纤细的纤维血管间隔,3例肿瘤组织内见砂砾体。免疫组织化学显示:10例肿瘤组织均表达TFE3,Melan-A, p504S及CK,不同程度表达Vimentin, CD10, RCC, PAX8和EMA,不表达CK7和CD117;9例获得随访,其中1例死亡,1例肺转移,7例均无复发和转移。结论:X p11.2RCC是一种少见的肾癌类型,具有相对特征性的组织学形态和免疫表型,准确诊断对于后续临床治疗至关重要。 展开更多
关键词 肾细胞癌 Xp11.2易位 TFE3基因融合
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The TGFβ superfamily in cardiac dysfunction
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作者 Jian Wu Olan Jackson-Weaver Jian Xu 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2018年第4期323-335,共13页
TGF 总科包括转变生长因素 s (TGF ) ,骨头形态基因的蛋白质(BMP )(GDF ) ,生长和区别因素和 ligands 的 Activin/Inhibin 家庭。在 TGF 总科 ligands 的 33 个成员之中,许多在心以内对房间的多重类型起作用,包括 cardiomyocytes,... TGF 总科包括转变生长因素 s (TGF ) ,骨头形态基因的蛋白质(BMP )(GDF ) ,生长和区别因素和 ligands 的 Activin/Inhibin 家庭。在 TGF 总科 ligands 的 33 个成员之中,许多在心以内对房间的多重类型起作用,包括 cardiomyocytes,心脏的 fibroblasts/myofibroblasts,冠的 endothelial 房间,光滑的肌肉房间,和有免疫力的房间(例如单核白血球 / 巨噬细胞和 neutrophils ) 。在这评论,我们在不同心脏的居住细胞的部件在 TGF, BMP,和 GDF 上加亮最近的发现,与在心开发,损害修理,和机能障碍的功能的影响联合。明确地,我们将在心脏的肥大,纤维变性,收缩性,新陈代谢, angiogenesis,和新生考察 TGF, BMP,和 GDF 的角色。 展开更多
关键词 机能障碍 TGF 心脏 生长因素 巨噬细胞 形态基因 新陈代谢 BMP
A Method for Normal Direction Judge Applied in Electrocardiographic Problem 预览
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作者 Chengcheng Tang Jian Wu Riqing Chen 《生物科学与医学(英文)》 2018年第1期1-8,共8页
Boundary Element Method (BEM) is widely used in electrocardiographic (ECG) problem. Formulations of these problems based on mathematical and numerical approximations of the known source in heart and the volume conduct... Boundary Element Method (BEM) is widely used in electrocardiographic (ECG) problem. Formulations of these problems based on mathematical and numerical approximations of the known source in heart and the volume conductor that can transfer voltages on the surface of the body. To analyze the electric potentials on body surface or epicardial surface, a set of discrete equations derived from a boundary integral equations need to be solved. Solving these equations means to get the potential distribution eventually. In the process of solving, transfer matrix of discrete equations has received considerable attention, how to get an appropriate transfer matrix is an important issue. This paper found that the direction of normal vector could affect the results when calculating the transfer matrix and presents a method analogous to Mesh Current Method to deal with this direction problem. Several simulations have been carried out to verify the accurate results with the correct direction of normal vector using new method within a torso model given simultaneous epicardial and body surface potential recordings. 展开更多
关键词 ECG PROBLEM BEM Transfer Matrix NORMAL VECTOR Direction
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Regional warming induced by urban surface expansion in Shanghai 预览
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作者 ZHAO De-Ming WU Jian 《大气和海洋科学快报:英文版》 CSCD 2018年第3期228-235,共8页
如何量化城市下垫面扩张对增暖的贡献,减小气候变化评估和预估的不确定性,是城市化影响研究中的一个难点。本文基于卫星遥感得到的反映过去三十多年城市下垫面扩张的土地利用数据,开展高分辨率的嵌套数值试验,量化了城市下垫面扩张在上... 如何量化城市下垫面扩张对增暖的贡献,减小气候变化评估和预估的不确定性,是城市化影响研究中的一个难点。本文基于卫星遥感得到的反映过去三十多年城市下垫面扩张的土地利用数据,开展高分辨率的嵌套数值试验,量化了城市下垫面扩张在上海不同空间尺度上对增暖的贡献。城市下垫面扩张对整个区域增暖的贡献在19%左右,而城市下垫面扩张区(N2U)的贡献比一直是城市下垫面区域(U2U)要高得多,分别在42%和17%左右。同时城市下垫面扩张对最低温度的增加强于最高温度的变化,日较差减小,尤其在城市下垫面扩张区更加显著。 展开更多
关键词 城市下垫面扩张 气温 区域增暖 嵌套试验 增暖趋势
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Evaluating the impacts of land use and land cover changes on surface air temperature using the WRF-mosaic approach 预览
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作者 ZHAO De-Ming WU Jian 《大气和海洋科学快报:英文版》 CSCD 2018年第3期262-269,共8页
如何量化土地利用/覆盖变化(LUCC)对区域气候的影响,是人类活动影响气候变化研究中的一个难点。本文利用卫星遥感反映过去三十年东亚区域土地利用变化数据,基于Mosaic近似考虑土地利用及其变化次网格尺度过程,量化了LUCC对地表辐射收... 如何量化土地利用/覆盖变化(LUCC)对区域气候的影响,是人类活动影响气候变化研究中的一个难点。本文利用卫星遥感反映过去三十年东亚区域土地利用变化数据,基于Mosaic近似考虑土地利用及其变化次网格尺度过程,量化了LUCC对地表辐射收支及气温的影响。过去三十年土地利用/覆盖变化对东亚区域总体呈降温效应(中国东部地区增温效应),LUCC导致的地表反照率变化影响地表辐射收支,中国和东亚区域的辐射强迫分别为-0.56 W m~(-2)和-0.50 W m~(-2)。 展开更多
关键词 土地利用/覆盖变化 气温 反照率 辐射收支 数值模拟
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Massive GGAAs in genomic repetitive sequences serve as a nuclear reservoir of NF-κB
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作者 Jian Wu Qiao Wang +3 位作者 Wei Dai Wei Wang Ming Yue Jinke Wang 《遗传学报:英文版》 SCIE CAS CSCD 2018年第4期193-203,共11页
原子因素 B (NF-B ) 是一个 DNA 有约束力的抄写因素。描绘它的 genomic 绑定地点为理解它的基因是关键的在房间的规章的功能和机制。这研究在肿瘤神经过敏因素描绘了 NF-B RelA/p65 的有约束力的地点 --(TNF ) 由精确染色质定序 immuno... 原子因素 B (NF-B ) 是一个 DNA 有约束力的抄写因素。描绘它的 genomic 绑定地点为理解它的基因是关键的在房间的规章的功能和机制。这研究在肿瘤神经过敏因素描绘了 NF-B RelA/p65 的有约束力的地点 --(TNF ) 由精确染色质定序 immunoprecipitation (ChIP-seq ) 刺激了 HeLa 房间。结果表明 NF-B 绑包含保存 GGAA 四胞胎的 nontraditional 主题(nt 主题) 。而且, nt 主题主要在附近的山峰散布包含象卫星,简单重复和短散布原子元素(正弦) 那样的很多重复元素的着丝点。这个细胞内部的有约束力的模式然后被证实由在里面 ? vitro 察觉,显示那 NF-B dimers 能绑 nontraditional B (nt-B ) 有低亲密关系的地点。然而,这绑定几乎不激活抄写。这研究因此推断 NF-B 有约束力的 nt 主题可以作为 NF-B 有约束力的传统的主题(t 主题) 认识到除基因规定以外的功能。证明推理,另外的房间线的许多 ChIP-seq 数据然后被分析。结果显示 NF-B 有约束力的 nt 主题在另外的房间也是广泛地在场的。ChIP-seq 数据分析也表明 nt 主题更广泛地与低褶层的丰富在山峰散布。重要地, NF-B 有约束力的 nt 主题主要是在休息房间的现在,这也被发现,而 NF-B 有约束力的 t 主题主要是在刺激房间的现在。极度,没有已知的功能被 nt 主题山峰的基因注解充实。把结果基于这些,这研究建议广泛地在大量重复元素散布的 nt-B 地点作为 NF-B 的一座原子水库工作。在休息房间在 nt-B 地点存储的原子 NF-B 蛋白质可以为在刺激之上调整它的目标基因被招募到 t-B 地点。 展开更多
关键词 原子 重复序列 水库 NF-KB 目标基因 服务 约束力 HELA
Evaluating the contributions of urban surface expansion to regional warming in Shanghai using different methods to calculate the daily mean temperature 预览
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作者 ZHAO De-Ming WU Jian 《大气和海洋科学快报:英文版》 CSCD 2018年第6期518-525,共8页
本文利用反映过去三十多年中国城市下垫面扩张的土地利用遥感数据开展高分辨率数值试验,比较了基于不同方法计算日平均气温(一天四次平均T4,日最高和最低气温平均Txn)对量化上海城市下垫面扩张增暖贡献的影响。不考虑城市下垫面变化,T4... 本文利用反映过去三十多年中国城市下垫面扩张的土地利用遥感数据开展高分辨率数值试验,比较了基于不同方法计算日平均气温(一天四次平均T4,日最高和最低气温平均Txn)对量化上海城市下垫面扩张增暖贡献的影响。不考虑城市下垫面变化,T4和Txn计算的增温趋势在不同子区域(城市-城市(U2U),非城市-城市(N2U)和整个区域)基本一致,考虑城市下垫面扩张后,T4和Txn计算的增温趋势在城市下垫面扩张区差别明显。基于T4和Txn计算的增暖贡献差异主要源于城市下垫面扩张对日最高和最低气温的影响不同。 展开更多
关键词 城市下垫面扩张 城市化增温 气温 最高气温 最低气温
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Comparisons of urban-related warming for Shenzhen and Guangzhou 预览
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作者 ZHAO Deming ZHA Jinlin WU Jian 《大气和海洋科学快报:英文版》 CSCD 2018年第4期330-337,共8页
本文利用基于卫星遥感资料反映过去几十年中国、尤其是三大城市群区(京津冀、长三角和珠三角)城市下垫面扩张的土地利用数据,开展高分辨率的嵌套数值试验,定量评估并比较了珠三角城市群区广州/深圳城市下垫面扩张对增暖的贡献。广州/深... 本文利用基于卫星遥感资料反映过去几十年中国、尤其是三大城市群区(京津冀、长三角和珠三角)城市下垫面扩张的土地利用数据,开展高分辨率的嵌套数值试验,定量评估并比较了珠三角城市群区广州/深圳城市下垫面扩张对增暖的贡献。广州/深圳大尺度气候背景场类似,城市化对城市下垫面区域增暖贡献接近(35%/44%),但对整个城市区的增暖贡献差别明显(17%/35%)。城市下垫面扩张对最高和最低气温的影响都表现为增温趋势,但最低气温增加趋势更加显著,日较差表现为减小的趋势。 展开更多
关键词 城市下垫面扩张 广州 深圳 城市增暖 数值模拟
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Characterization of a laccase from a wood-feeding termite, Coptotermes formosanus
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《昆虫科学:英文版》 SCIE CAS CSCD 2018年第2期251-258,共8页
关键词 白蚁 氧化还原作用 直接氧化 对苯二酚 FENTON H202 木质素 生物资源
High-power linearly-polarized tunable Raman fiber laser
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作者 宋家鑫 吴函烁 +4 位作者 许将明 张汉伟 叶俊 吴坚 周朴 《中国物理B:英文版》 SCIE EI CAS CSCD 2018年第9期316-321,共6页
关键词 拉曼激光 激光系统 纤维 极化 线性 高反射率 变换效率 镜子
The clinical and genetic characteristics in children with mitochondrial disease in China
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作者 Fang Fang Zhimei Liu +11 位作者 Hezhi Fang Jian Wu Danmin Shen Suzhen Sun Changhong Ding Tongli Han Yun Wu Junlan Lv Lei Yang Shufang Li Jianxin Lv Ying Shen 《中国科学:生命科学英文版》 SCIE CAS CSCD 2017年第7期746-757,共12页
Mitochondrial disease was a clinically and genetically heterogeneous group of diseases, thus the diagnosis was very difficult to clinicians. Our objective was to analyze clinical and genetic characteristics of childre... Mitochondrial disease was a clinically and genetically heterogeneous group of diseases, thus the diagnosis was very difficult to clinicians. Our objective was to analyze clinical and genetic characteristics of children with mitochondrial disease in China. We tested 141 candidate patients who have been suspected of mitochondrial disorders by using targeted next-generation sequencing(NGS), and summarized the clinical and genetic data of gene confirmed cases from Neurology Department, Beijing Children's Hospital, Capital Medical University from October 2012 to January 2015. In our study, 40 cases of gene confirmed mitochondrial disease including eight kinds of mitochondrial disease, among which Leigh syndrome was identified to be the most common type, followed by mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes(MELAS). The age-of-onset varies among mitochondrial disease, but early onset was common. All of 40 cases were gene confirmed, among which 25 cases(62.5%)with mitochondrial DNA(mtDNA) mutation, and 15 cases(37.5%) with nuclear DNA(nDNA) mutation. M.3243A>G(n=7)accounts for a large proportion of mtDNA mutation. The nDNA mutations include SURF1(n=7),PDHA1(n=2),and NDUFV1,NDUFAF6, SUCLA2, SUCLG1, RRM2 B, and C12orf65, respectively. 展开更多
关键词 北京儿童医院 线粒体病 临床医生 遗传特点 MTDNA突变 中国 线粒体疾病 基因突变
A national report from China Liver Transplant Registry: steroid avoidance after liver transplantation for hepatocellular carcinoma 预览
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作者 Qiang Wei Feng Gao +8 位作者 Runzhou Zhuang Qi Ling Qinghong Ke Jian Wu Tian Shen Mangli Zhang Min Zhang Xiao Xu Shusen Zheng 《中国癌症研究:英文版》 SCIE CAS CSCD 2017年第5期426-437,共12页
Objective:We aimed to evaluate the efficacy and safety of steroid-free immunosuppression after liver transplantation(LT)for hepatocellular carcinoma(HCC).Methods:We retrospectively analyzed HCC recipients without ster... Objective:We aimed to evaluate the efficacy and safety of steroid-free immunosuppression after liver transplantation(LT)for hepatocellular carcinoma(HCC).Methods:We retrospectively analyzed HCC recipients without steroids after LT(SF group,n=368)based on the China Liver Transplant Registry(CLTR)database.These recipients were matched 1:2 with patients using steroids(S group,n=736)for the same period after LT for HCC,according to propensity scores.Results:Multivariate analysis indicates that recipients with younger age[odds ratio(OR),1.053;P=0.011],preoperative hepatitis B virus(HBV)DNA≥1,000 copies/mL(OR,2.597;P=0.004)and beyond Milan criteria(OR,4.255;P<0.001)were identified as the risk factors associated with tumor recurrence in steroid avoidance recipients after LT.The patients fulfilling the Milan criteria in the SF group presented higher overall and tumor-free survival rates than those in the S group(P<0.05).Multivariate analysis revealed that recipient beyond Milan criteria was an independent prognostic factor for overall survival(OR,1.690;P<0.001)and tumor-free survival(OR,2.066;P<0.001).The incidences of new-onset diabetes mellitus(21.20% vs.33.29%,P<0.001),new-onset hypertension(10.05%vs.18.61%,P<0.001)and hyperlipidemia(4.08% vs.7.20%,P=0.042)were significantly lower in the SF group.Conclusions:Steroid-free immunosuppression could be safe and feasible for HBV-related HCC patients in LT.Age,HBV DNA level and Milan criteria maybe risk factors associated with tumor recurrence in steroid avoidance recipients.Recipient beyond Milan criteria was an independent prognostic factor and recipient fulfilling Milan criteria can benefit the most from steroid-free immunosuppression. 展开更多
关键词 肝移植 类固醇 中国 回避 HCC 免疫力 后评估
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在单个磁珠的水平上探究磁珠的有效免疫反应体积
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作者 Rui WANG Yuan CHEN +3 位作者 Kai FAN Feng JI Jian WU Yong-hua YU 《浙江大学学报:B卷英文版》 SCIE CAS CSCD 2017年第10期845-853,共9页
目的:通过探究单个磁珠的有效免疫反应体积(NEIV),在微观水平上揭示磁珠的免疫反应过程,为大体积样本检测过程中磁珠的用量提供理论指导。创新点:首次提出"单个磁珠的有效免疫反应体积"这一概念,提出在微观水平上对磁珠免疫反应... 目的:通过探究单个磁珠的有效免疫反应体积(NEIV),在微观水平上揭示磁珠的免疫反应过程,为大体积样本检测过程中磁珠的用量提供理论指导。创新点:首次提出"单个磁珠的有效免疫反应体积"这一概念,提出在微观水平上对磁珠免疫反应进行探究,为进一步研究磁珠-抗原免疫反应的动力学过程打下基础。方法:首先,采用两种直径的磁珠对50μl不同浓度的抗原进行比色检测,证明磁珠上抗原的结合位点过量。随后,采用定量磁珠对相同浓度不同体积的抗原进行检测,得出"单个磁珠的有效免疫反应体积"这一概念。接着,采用三种不同用量的磁珠对浓度相同、体积梯度增大的抗原进行检测,以验证所提出的NEIV的概念。然后,通过测定孵育时长、孵育温度和震荡与否对比色结果的影响,找到对NEIV影响的关键因素。最后采用定量磁珠,对梯度稀释的抗原进行检测,建立磁珠用量与比色结果的关系,对NEIV的实际应用提出展望。结论:对于同一直径的磁珠,在相同的孵育条件下,其单个磁珠的NEIV是恒定的,与磁珠用量和孵育体积无关。孵育温度、孵育时长和震荡与否是影响NEIV值的关键因素。采用NEIV这一参数可以在大体积样本检测之前,对磁珠的用量模拟提供有效指导。除此之外,NEIV更从微观角度上揭示了磁珠和抗原的免疫反应过程,为进一步研究磁珠-抗原免疫反应的动力学过程奠定了基础。 展开更多
关键词 单个磁珠有效免疫反应体积(NEIV) 免疫磁珠 酶联免疫吸附测定(ELISA) 磁珠直径 孵育方式
Near-diffraction-limited linearly polarized narrow-linewidth random fiber laser with record kilowatt output
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作者 JIANGMING XU LONG HUANG +6 位作者 MAN JIANG JUN YE PENGFEI MA JINYONG LENG JIAN WU HANWEI ZHANG PU ZHOU 《光子学研究:英文版》 2017年第4期350-354,共5页
In this paper, we propose and experimentally investigate a linearly polarized narrow-linewidth random fiber laser(RFL) operating at 1080 nm and boost the output power to kilowatt level with near-diffraction-limited be... In this paper, we propose and experimentally investigate a linearly polarized narrow-linewidth random fiber laser(RFL) operating at 1080 nm and boost the output power to kilowatt level with near-diffraction-limited beam quality using a master oscillation power amplifier. The RFL based on a half-opened cavity, which is composed of a linearly polarized narrow-linewidth fiber Bragg grating and a 500 m piece of polarization-maintained Ge-doped fiber, generates a 0.71 W seed laser with an 88 pm full width at half-maximum(FWHM) linewidth and a 22.5 dB polarization extinction ratio(PER) for power scaling. A two-stage fiber amplifier enhances the seed laser to the maximal 1.01 k W with a PER value of 17 dB and a beam quality of M_x~2=1.15 and M_y~2=1.13. No stimulated Brillouin scattering effect is observed at the ultimate power level, and the FWHM linewidth of the amplified random laser broadens linearly as a function of the output power with a coefficient of about 0.1237 pm∕W.To the best of our knowledge, this is the first demonstration of a linearly polarized narrow-linewidth RFL with even kilowatt-level near-diffraction-limited output, and further performance scaling is ongoing. 展开更多
Passively spatiotemporal gain-modulation-induced stable pulsing operation of a random fiber laser
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作者 JIANGMING XU JUN YE +4 位作者 WEI LIU JIAN WU HANWEI ZHANG JINYONG LENG PU ZHOU 《光子学研究:英文版》 2017年第6期117-122,共6页
Unlike a traditional fiber laser with a defined resonant cavity, a random fiber laser(RFL), whose operation is based on distributed feedback and gain via Rayleigh scattering(RS) and stimulated Raman scattering in a lo... Unlike a traditional fiber laser with a defined resonant cavity, a random fiber laser(RFL), whose operation is based on distributed feedback and gain via Rayleigh scattering(RS) and stimulated Raman scattering in a long passive fiber, has fundamental scientific challenges in pulsing operation for its remarkable cavity-free feature. For the time being, stable pulsed RFL utilizing a passive method has not been reported. Here, we propose and experimentally realize the passive spatiotemporal gain-modulation-induced stable pulsing operation of counterpumped RFL. Thanks to the good temporal stability of an employed pumping amplified spontaneous emission source and the superiority of this pulse generation scheme, a stable and regular pulse train can be obtained.Furthermore, the pump hysteresis and bistability phenomena with the generation of high-order Stokes light is presented, and the dynamics of pulsing operation is discussed after the theoretical investigation of the counterpumped RFL. This work extends our comprehension of temporal property of RFL and paves an effective novel avenue for the exploration of pulsed RFL with structural simplicity, low cost, and stable output. 展开更多
Analysis of incoherent scatter during ionospheric heating near the fifth electron gyrofrequency
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作者 吴军 吴健 +1 位作者 赵海生 许正文 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2017年第4期34-41,共8页
The observation of ultra-high frequency radar during an ionospheric heating experiment carried out at Troms(?)site of European Incoherent Scatter Scientific Association,Norway,is analyzed.When pump is operating slight... The observation of ultra-high frequency radar during an ionospheric heating experiment carried out at Troms(?)site of European Incoherent Scatter Scientific Association,Norway,is analyzed.When pump is operating slightly above the fifth electron gyrofrequency,some strong enhancements in radar echo and electron density occur in a wide altitude range and are in sync with the shifting and spread of plasma line around the reflection altitude,which may be due to the focusing or collimating of radar wave by irregularities.While some strong enhancements in electron density and radar echo around the reflection altitude do not correspond to the true increase in electron density,but due to the enhanced ion acoustic wave by parametric decay instability and oscillation two stream instability.In addition,the different heating rates and cooling rates at the pump frequencies below,around and above fifth gyrofrequency respectively result in the dependence of the enhancements in electron temperature on the pump frequency. 展开更多
关键词 回转频率 非相干散射 电离层加热 电子回旋 双流不稳定性 电子密度 雷达回波 泵运行
Altitude and intensity characteristics of parametric instability excited by an HF pump wave near the fifth electron harmonic
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作者 吴军 吴健 +3 位作者 M T RIETVELD I HAGGSTROM 赵海生 许正文 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2017年第12期50-56,共7页
国际税收竞争效应分析:一个理论分析框架 被引量:1
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作者 蔡建勋 沈向民 吴健 《国际税收》 北大核心 2017年第10期77-81,共5页
国际税收竞争是经济全球化的产物,具有正面效应和负面效应。一般对国际税收竞争效应的分析主要是建立在政府是“自利”或是“善良”的假定基础上。多数学者认为适度的国际税收竞争是有利的。本文通过一个理论分析模型说明在不同情况下... 国际税收竞争是经济全球化的产物,具有正面效应和负面效应。一般对国际税收竞争效应的分析主要是建立在政府是“自利”或是“善良”的假定基础上。多数学者认为适度的国际税收竞争是有利的。本文通过一个理论分析模型说明在不同情况下的国际竞争对于国民福利水平的影响,从福利效应的角度分析了公共选择过程中,中间投票人的经济地位与国际税收竞争福利效应之间的关系。 展开更多
关键词 福利效应 中间投票人 拉姆齐法则 边际超额负担
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