检索结果-南通市图书馆

Reliable intracavity reflection for self-injection locking lasers and microcomb generation

Photonics Research 2024年第5期12卷 I0001-I0010页

作者： BITAO SHEN XUGUANG ZHANG YIMENG WANG ZIHAN TAO HAOWEN SHU huajin chang WENCAN LI YAN ZHOU Zhangfeng Ge RUIXUAN CHEN BOWEN BAI LIN chang XINGJUN WANG State Key Laboratory of Advanced Optical Communications System and Networks School of ElectronicsPeking UniversityBeijing 100871China Peng Cheng Laboratory Shenzhen 518055China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China Frontiers Science Center for Nano-optoelectronics Peking UniversityBeijing 100871China

Self-injection locking has emerged as a crucial technique for coherent optical sources,spanning from narrow linewidth lasers to the generation of localized *** technique involves key components,namely a laser diode and a high-quality cavity that induces narrow-band reflection back into the laser ***,in prior studies,the reflection mainly relied on the random intracavity Rayleigh backscattering,rendering it unpredictable and unsuitable for large-scale production and wide-band *** this work,we present a simple approach to achieve reliable intracavity reflection for self-injection locking to address this challenge by introducing a Sagnac loop into the *** method guarantees robust reflection for every resonance within a wide operational band without compromising the quality factor or adding complexity to the fabrication *** a proof of concept,we showcase the robust generation of narrow linewidth lasers and localized microcombs locked to different resonances within a normal-dispersion ***,the existence and generation of localized patterns in a normal-dispersion cavity with broadband forward–backward field coupling is first proved,as far as we know,both in simulation and in *** research offers a transformative approach to self-injection locking and holds great potential for large-scale production.

关键词： intracavity injection locking

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

当代大学生第二外语学习意向调查研究——以湖北文理学院为例

引用

湖北文理学院学报 2024年第3期45卷 62-66页

作者：赵荣常华进湖北文理学院外国语学院湖北襄阳441053 湖北文理学院教务处湖北襄阳441053

为了解当代大学生第二门外语的学习现状及意向动机,项目组对湖北文理学院在校学生展开线上问卷调查。调查显示,大多数学生仅学习英语一门外语,但为拓宽自己的就业渠道,他们有强烈的意愿选择自己感兴趣的语言作为第二外语在校内进行线下... 详细信息

为了解当代大学生第二门外语的学习现状及意向动机,项目组对湖北文理学院在校学生展开线上问卷调查。调查显示,大多数学生仅学习英语一门外语,但为拓宽自己的就业渠道,他们有强烈的意愿选择自己感兴趣的语言作为第二外语在校内进行线下课堂学习,内容以掌握日常交际用语和语言国家文化为主。目前,因时间精力不足、学习路径不畅等原因未能达成意愿。由此建议学校赋予学生外语学习自主选择权,充分利用现有资源,满足学生第二外语学习的意愿,助力国家建构公共外语多元化格局,促进学生自由全面发展,进而为社会培养“专业+多语种”复合型人才。

关键词：第二外语学习意向外语教学

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于虚拟仿真试验平台的测量与地图学课程教学改革探讨——以湖北文理学院地理科学专业为例

引用

创新创业理论研究与实践 2024年第14期7卷 32-36,49页

作者：陈威李权国常华进周俭清翟月湖北文理学院湖北襄阳441053 襄阳市测绘研究院湖北襄阳441001 大地测量与地球动力学国家重点实验室湖北武汉430077

随着信息技术的快速发展,基于虚拟仿真的测绘类试验软件正逐步成为普通高等院校测绘类课程教学中的重要工具。湖北文理学院地理科学专业通过引入虚拟仿真试验平台——数字测图虚拟仿真软件,对传统的测量与地图学课程进行了教学改革,包... 详细信息

随着信息技术的快速发展,基于虚拟仿真的测绘类试验软件正逐步成为普通高等院校测绘类课程教学中的重要工具。湖北文理学院地理科学专业通过引入虚拟仿真试验平台——数字测图虚拟仿真软件,对传统的测量与地图学课程进行了教学改革,包括以“课赛融通”为前提、融入课程思政、完善“线上+线下”混合式教学及扩大校企合作空间,教学改革的初步成效可为其他开设测绘类课程的同类高校在教学模式方面提供借鉴和参考。

关键词：虚拟仿真测量与地图学教学改革数字测图地理科学专业人才培养

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Submilliwatt, widely tunable coherent microcomb generation with feedback-free operation

引用

Advanced Photonics 2023年第3期5卷 144-154页

作者： Haowen Shu Lin chang Chenghao Lao Bitao Shen Weiqiang Xie Xuguang Zhang Ming Jin Yuansheng Tao Ruixuan Chen Zihan Tao huajin chang Shaohua Yu Qifan Yang Xingjun Wang John E.Bowers Peking University School of ElectronicsState Key Laboratory of Advanced Optical Communication Systems and NetworksBeijingChina University of California Santa BarbaraDepartment of Electrical and Computer EngineeringSanta BarbaraCaliforniaUnited States Peking University School of PhysicsState Key Laboratory for Artificial Microstructure and Mesoscopic PhysicsBeijingChina Peng Cheng Laboratory ShenzhenChina Peking University Frontiers Science Center for Nano-OptoelectronicsBeijingChina

Microcombs are revolutionizing optoelectronics by providing parallel, mutually coherent wavelengthchannels for time-frequency metrology and information processing. To implement this essential function inintegrated photonic systems, it is desirable to drive microcombs directly with an on-chip laser in a simpleand flexible way. However, two major difficulties have prevented this goal: (1) generating mode-lockedcomb states usually requires a significant amount of pump power and (2) the requirement to align laser andresonator frequency significantly complicates operation and limits the tunability of the comb lines. Here, weaddress these problems by using microresonators on an AlGaAs on-insulator platform to generate dark-pulsemicrocombs. This highly nonlinear platform dramatically relaxes fabrication requirements and leads to arecord-low pump power of <1 mW for coherent comb generation. Dark-pulse microcombs facilitated bythermally controlled avoided mode crossings are accessed by direct distributed feedback laser *** any feedback or control circuitries, the comb shows good coherence and stability. With around150 mW on-chip power, this approach also leads to an unprecedentedly wide tuning range of over one freespectral range (97.5 GHz). Our work provides a route to realize power-efficient, simple, and reconfigurablemicrocombs that can be seamlessly integrated with a wide range of photonic systems.

关键词： dark-pulse microcomb direct pumping scheme widely tunable source

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Terminal Ediacaran anoxia in deep-ocean: Trace element evidence from cherts of the Liuchapo Formation, South China

引用

Science China Earth Sciences 2009年第6期52卷 807-822页

作者： chang huajin CHU XueLei FENG LianJun HUANG Jing State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China

Here we report a detailed trace element study of the cherts from Liuchapo Formation, which is a terminal Ediacaran (551-542 Ma) succession in South China deposited in deep-water basinal setting. The REE of Liuchapo cherts shows similar features as observed for anoxic modern seawater (but not for hydrothermal fluids), characterized by positive La anomaly (LaN/CeN = 0.83-1.91, average 1.37), moderately negative Ce anomaly (0.53-1.1, average 0.73), positive Gd anomaly (average 1.08), positive Y anomaly (average 1.21), and depleted LREE and MREE. In addition, the Liuchapo cherts have low ΣREE (3.36-56.13 ppm, average 20.6 ppm), low Al2O3, Ti, Th and Zr concentrations, and high Y/Ho ratios (up to 43.9). The redox-sensitive trace elements concentrations in the cherts do not correlate with detrital input proxies. All of these features suggest that the redox-sensitive trace elements in the cherts were authigenically concentrated in water column and their concentrations thus are excellent indicators of ancient redox conditions. Very low Th/U ratios, high V/(V+Ni) and FeT/Al ratios, enrichments of redox-sensitive trace elements (U, V, Mo), and low concentration of Mn in the cherts imply anoxia in the deep seawater. Our data reveal that the terminal Ediacaran ocean was not completely oxidized and the deep ocean was still anoxic, at least in South China. We propose that although the oxidative events existed in the terminal Ediacaran oceans, decomposition of organic matter prolonged anoxia in the deep ocean.

关键词： chert anoxia trace elements redox proxy Ediacaran South China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Iron speciation in cherts from the Laobao Formation,South China:Implications for anoxic and ferruginous deep-water conditions

引用

Chinese Science Bulletin 2010年第27期55卷 3189-3196页

作者： chang huajin CHU XueLei FENG LianJun HUANG Jing School of Life and Geography Sciences Qinghai Normal University Xining 810008 China Key Laboratory of Tibetan Plateau Environment and Resources Ministry of Education Xining 810008 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Cherts in the Laobao Formation in the Silikou section,South China were deposited in terminal Ediacaran *** speciations of iron in cherts,such as pyrite Fe(FeP),HCl-extractable Fe(FeH),and total Fe(FeT),and their interrelationships,are proxies for distinguishing oxic,anoxic but ferruginous,and sulfidic conditions,which is an effective method for studying the terminal Ediacaran ocean *** chert samples from the Laobao Formation,pyrite concentrations are generally low(<0.56%),degree of pyritization(DOP)ranges from<0.01 to 0.78 and most are<0.45;(FeP+FeH)/FeT ratios are between 0.27 and 0.84 and most exceed 0.38,and most of FeT/Al ratios range from 0.55 to 5.87(averaging 1.1).Relatively high content of highly reactive Fe and low content of pyrite indicate a scarcity of H2S and Fe-enriched *** features suggested that the deposition setting of Laobao cherts was anoxic and *** Ediacaran deep-water in the South China Basin was most likely anoxic and ferruginous,which played a key role in the emergence and evolution of early multicellular life.

关键词：深水条件硅质岩铁质缺氧中国 o形形态场效应晶体管

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

新型研发机构研究综述与展望

引用

科技创业月刊 2022年第3期35卷 156-162页

作者：谢晓洁常华进华南协同创新研究院广东东莞523808 湖北文理学院资源环境与旅游学院湖北襄阳441053

运用文献调研法和内容分析法,梳理其研究的变迁过程,可为未来研究提供方向。现有关于新型研发机构的研究为行业发展提供了政策与理论指导;其研究变迁过程呈现功能研究的拓展性、支持研究的时代针对性、运行机制研究的整合性、提质增效... 详细信息

运用文献调研法和内容分析法,梳理其研究的变迁过程,可为未来研究提供方向。现有关于新型研发机构的研究为行业发展提供了政策与理论指导;其研究变迁过程呈现功能研究的拓展性、支持研究的时代针对性、运行机制研究的整合性、提质增效研究的深刻性、评价研究模型建设的可测性、研究趋势的具体性与实用性等特点。随着结构变迁,其模式、政策与资金支持、内外协调上出现新的情况。未来可开展促进新结构模式建设、推进新结构支持性政策、增进新结构协调机制的研究,以适应新的发展需求。

关键词：新型研发机构研究变迁综述展望

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

草莓状黄铁矿与古海洋环境恢复

引用

地球科学进展 2011年第5期26卷 475-481页

作者：常华进储雪蕾青海师范大学生命与地理科学学院青海西宁810008 青藏高原环境与资源教育部重点实验室青海西宁810008 中国科学院地质与地球物理研究所北京100029

草莓状黄铁矿是指由等粒度的亚微米级黄铁矿晶体或微晶体紧密堆积而成,形似草莓的黄铁矿球形集合体。它们在氧化和缺氧海洋环境中形成的机理不同,沉积岩中草莓状黄铁矿的粒径分布特征是恢复古海洋的氧化还原状态行之有效的方法之一。然... 详细信息

草莓状黄铁矿是指由等粒度的亚微米级黄铁矿晶体或微晶体紧密堆积而成,形似草莓的黄铁矿球形集合体。它们在氧化和缺氧海洋环境中形成的机理不同,沉积岩中草莓状黄铁矿的粒径分布特征是恢复古海洋的氧化还原状态行之有效的方法之一。然而,草莓状黄铁矿粒径统计仅能区分出氧化和缺氧硫化的环境,不能进一步区分缺氧程度及状态(如次氧化、缺氧含铁等)。桂北泗里口老堡组硅岩沉积于埃迪卡拉纪末期,它们所记录的草莓状黄铁矿粒径分布特征指示了硫化的深水古环境,这与用氧化还原敏感元素等方法获得的深水是缺氧含铁的结论矛盾。这可能是由于当时盆地水体中硫酸盐含量低,细菌硫酸盐还原生成的H2S少,导致形成了粒径小的黄铁矿。在运用草莓状黄铁矿恢复古海洋环境时,还应与其他地球化学手段,如沉积岩中Fe组分、氧化还原敏感元素、稳定同位素等结合才能获得确切的古海洋氧化还原状态。

关键词：草莓状黄铁矿氧化还原状态古海洋

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A sulfate control on marine mid-depth euxinia on the early Cambrian(ca. 529–521 Ma) Yangtze platform, South China

A sulfate control on marine mid-depth euxinia on the early C...

引用

中国科学院地质与地球物理研究所2014年度（第14届）...

作者： Lianjun Feng Chao Li Jing Huang huajin chang Xuelei Chu Institute of Geology and Geophysics Chinese Academy of Sciences Key Laboratory for Mineral Resources Chinese Academy of Sciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Science University of Science and Technology of China School of Life and Geography Sciences Qinghai Normal University

Given the high oxygen demands of complex metazoans, a sound understanding of marine redox conditions is essential to reconstruct the factors that lead to the dramatic increases in ecosystem complexity and biological diversity in the early Cambrian. In this study, we report new Fe–Mo–C–S geochemical data from black shale-rich strata of the early Cambrian continental margin Yangjiaping section in the Yangtze platform, South China. Integrated Fe speciation and Mo abundance data from the Yangjiaping section, in combination with previously reported data from Shatan(inner shelf), Songtao(slope) and Longbizui(basinal) sections, suggest mid-depth euxinic waters coexisting with ferruginous deep waters and oxic surface waters. This redox structure is similar to conditions previously suggested for the Ediacaran Yangtze platform and other Proterozoic marine basins, indicating that Proterozoic layered ocean redox structure in some basins persisted into the early Cambrian. Furthermore, the Fe–Mo data demonstrate that the mid-depth euxinia was widespread during a marine transgression but shrank gradually along with widespread shelf oxygenation when the basin evolved into subsequent *** highly reactive iron(FeHR) in deep water with a hydrothermal origin may have had a control on the mid-depth euxinia, given geochemical and geological evidence for basinal hydrothermal *** the other hand, a sulfate limitation on bacterial sulfate reduction(BSR) and sulfide generation was suggested by a weak correlation(R2≤ 0.22) between pyrite iron versus FeHRand total organic carbon(TOC) form anoxic deep-water sections and high TOC(averagely 6%) in the deepest-ferruginous-water Longbizui section. Furthermore, a spatial gradient was observed in sulfur isotopic composition of pyrite(averagely from 0.2‰ to 21.0‰), consistent with a lateral gradient of sulfate in concentration or/and in isotope from shore to distal waters on the transgressive Yangtze platform. We accordingly prop

关键词： Yangtze platform Early Cambrian Mid-depth euxinia Iron speciation Sulfur isotope

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

华南老堡组硅质岩中草莓状黄铁矿--埃迪卡拉纪末期深海缺氧的证据

引用

岩石学报 2009年第4期25卷 1001-1007页

作者：常华进储雪蕾冯连君黄晶中国科学院地质与地球物理研究所北京100029 中国科学院矿产资源研究重点实验室北京100029 中国科学院研究生院北京100049

为恢复埃迪卡拉纪末期深海的氧化还原状态,我们对华南桂北泗里口剖面老堡组(大约550～540Ma)硅质岩中草莓状黄铁矿的粒径和分布进行了测量、统计和研究。老堡组硅质岩样品中普遍存在着草莓状黄铁矿,呈星散状分布,未见自形晶的黄铁矿颗... 详细信息

为恢复埃迪卡拉纪末期深海的氧化还原状态,我们对华南桂北泗里口剖面老堡组(大约550～540Ma)硅质岩中草莓状黄铁矿的粒径和分布进行了测量、统计和研究。老堡组硅质岩样品中普遍存在着草莓状黄铁矿,呈星散状分布,未见自形晶的黄铁矿颗粒和明显后期充填的草莓状黄铁矿集合体。硅质岩中草莓状黄铁矿颗粒的统计表明,它们具有很窄的变化范围,最大粒径小于18μm,大多数样品中草莓状黄铁矿的平均粒径和中间粒径均小于5μm。根据这些硅质岩中原生黄铁矿的粒径和分布,我们判定埃迪卡拉纪末期的深部海水是缺氧的。泗里口剖面老堡组硅质岩中草莓状黄铁矿的平均粒径、中间粒径和最大直径沿剖面向上逐渐增加,这意味着埃迪卡拉纪末期华南的深部海水有逐步被氧化的趋势。

关键词：黄铁矿硅质岩埃迪卡拉纪末期氧化还原状态古海洋

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：